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Hashamomuck Pond
Watershed Management Plan
July, 2006
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Prepared for:
The Peconic Estuary Program
HASHAMOMUCK POND
WATERSHED MANAGEMENT PLAN
' July 2006
Prepared by:
Horsley Witten Group, Inc.
Sandwich, Massachusetts
1
Prepared for:
' Peconic Estuary Program
Suffolk County Department of Public Health Services
Office of Ecology
' Riverhead,New York
' This report was prepared for the Peconic Estuary program with funding provided by the
U.S. Environmental protection Agency under assistance agreement No. CE982137-01-2
to the Peconic Estuary Program through the Suffolk County Department of Health
' Services. The mention of trade names or commercial products does not in any way
constitute an endorsement or recommendation for use.
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ACKNOWLEDGEMENTS
' Horsley Witten Group, Inc. would like to thank the Peconic Estuary Program for
guidance, information collection, and useful comments during the preparation of this
document. We thank the Suffolk County Soil and Water Conservation District and the
USDA, Natural Resources Conservation Service for their invaluable assistance in this
project. In addition, we thank the Peconic Estuary Bay Keeper for assistance in
' collecting field data that was integral to the accuracy of this report. We would also like
to thank the US EPA and New York State Department of Environmental Conservation
for comments on the final draft of this document.
' TABLE OF CONTENTS
'
Page
' i EXECUTIVE SUMMARY 1
' 1.0 INTRODUCTION 4
1.1 The Peconic Estuary 4
1.2 Project Background 6
' 1.3 Organization of the Plan 8
2.0 WATERSHED CHARACTERISTICS 9
' 2.1 Land Use Watershed Characterization 9
2.2 Pollutant Loading Assessment 12
2.3 Existing Land Development Review Process 16
' 2.4 Existing Stormwater Infrastructure and Maintenance 17
2.5 Future Buildout Pollutant Loading Assessment 18
' 3.0 STORMWATER MANAGEMENT PROGRAMMATIC
ASSESSMENT 23
3.1 Recommendations for Modifications to Land
' Development Review Process 23
3.2 Recommendations for Maintenance of Stormwater
Infrastructure 24
' 3.3 Public Education and Outreach—Recommended
Focus Areas 25
3.3.1 Waterfowl Management 26
' 3.3.2 Lawn Management 27
3.3.3 Pet Waste Management 28
3.3.4 Stormwater Management 28
' 3.3.5 Septic System Maintenance 29
3.4 Public Education and Outreach—Recommended
Programs 30
t 3.4.1 Watershed Awareness Day 30
3.4.2 Media Campaigns 30
3.4.3 Institution of an "Adopt-a-Watershed"
Organization 31
3.4.4 Demonstration Projects 31
3.4.5 Watershed Clean-up Days 31
' 3.4.6 School Watershed Science Programs 32
3.5 Summary of Programmatic Recommendations 32
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TABLE OF CONTENTS (Cont.) t
4.0 STORMWATER MANAGEMENT ASSESSMENT 33 ,
4.1 Assessment Methodology 33 '
4.2 Storm Drainage Assessment and Mapping 35
4.3 Potential Sites and Best Management Practices Selection 35
4.4 Description of Proposed Best Management Practices 38 '
4.5 Retrofit Ranking System 38
4.6 Investigated Sites and Selected BMP Descriptions 40
4.6.1 Site H-S- End of Laurel Avenue 42 '
4.6.2 Site H-7- Long Creek Drive 42
4.6.3 Site H-9- Bayview Avenue 43
4.6.4 Site H-14- Dons Way 43 ,
4.6.5 Site H-18- Intersection of Colony Road &
Bayview Avenue 44
4.6.6 Site H-22A- Intersection of Grove Road & '
Mill Creek Drive 44
4.6.7 Site H-2213- Grove Road 44
4.7 Unified Subwatershed and Site Reconnaissance 45 '
4.7.1 Neighborhood Source Assessment (NSA) 46
4.7.2 Hotspot Site Investigation (HIS) 47
4.7.3 Pervious Area Assessment(PAA) 48 '
4.7.4 Streets and Storm Drains (SSD) 48
5.0 HABITAT PROTECTION ASSESSMENT 50 '
6.0 REFERENCES 55
FIGURES '
Figure 1-1 Vicinity Map 5 '
Figure 2-1 Aerial Photograph 10
Figure 2-2 Land Use 11
Figure 2-3 Soils 13 '
Figure 2-4 Hashamomuck Pond Watershed—Highest Priority
Subwatersheds for fecal coliform loading under
existing and future conditions. 21 '
Figure 2-5 Hashamomuck Pond Watershed—Highest Priority
subwatersheds for nitrogen loading under existing
and future conditions. 21 '
Figure 4-1 Drainage Area and Subwatershed Map 34
Figure 4-2 Field Inventory Locations 36
Figure 5-1 Habitat Assessment 51 '
Figure C-1 Schematic of a Bioretention System C-1
Figure C-2 Schematic of a Micro-Bio Inlet C-4
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' TABLE OF CONTENTS (Cont.)
' Figure C-3 Schematic of a Shallow Marsh/Pocket Wetland C-5
Figure C-4 Schematic of a Dry Swale C-7
Figure C-5 Schematic of a Grassed Channel C-10
Figure C-6 Schematic of an Oil/Grit Separator C-11
Figure D-1 Best Management Practices (BMP) Sites—H-5 D-4
Figure D-2 Best Management Practices (BMP) Sites—H-7 D-9
' Figure D-3 Best Management Practices (BMP) Sites—H-9 D-12
Figure D-4 Best Management Practices (BMP) Sites—H-14 D-17
Figure D-5 Best Management Practices (BMP) Sites—H-18 D-20
Figure D-6 Best Management Practices (BMP) Sites—H-22A D-24
Figure D-7 Best Management Practices (BMP) Sites—H-22B D-28
' TABLES
Table 2-1 Hashamomuck Pond Watershed Existing Land Use
Summary 9
' Table 2-2 Summary of GIS-Based Bacteria and Nitrogen Loading
Model for Hashamomuck Pond 15
Table 2-3 Comparison of Average Embayment Concentrations
Predicted by the Model with Measured Concentrations in
Hashamomuck Pond 16
Table 2-4 Future Change in Land Use- Hashamomuck Pond
Watershed 19
Table 2-5 Summary of GIS-Based Future Bacteria and Nitrogen
Loading Model for Hashamomuck Pond 19
Table 4-1 Summary of Proposed BMP 37
Table 4-2 Retrofit Ranking Summary 41
Table 5-1 Parcel Summary Table 52
' Table C-1 Design Guidance for a Bioretention System C-2
Table C-2 Constructed Wetland Design Criteria C-6
Table C-3 Design Criteria for Dry Swales C-8
' Table C-4 Design Criteria for Grass Channels C-9
APPENDICES
Appendix A: Catch Basin Insert—Performance Data
Appendix B: Watershed Assessment Guide
Appendix C: Description of Proposed Best Management Practices
' Appendix D: Selected BMP Sites
D-1: Subwatershed H-5
D-2: Subwatershed H-7
' D-3: Subwatershed H-9
D-4: Subwatershed H-14
D-5: Subwatershed H-18
D-6: Subwatershed H-22A
D-7: Subwatershed H-22B
Appendix E: Unified Subwatershed and Site Reconnaissance
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i EXECUTIVE SUMMARY
' In 2001, the Peconic Estuary Program(PEP) adopted a final Comprehensive
Conservation and Management Plan (CCMP) for the Peconic Estuary and its watersheds.
' The plan identifies four priority management areas: control of pathogens, nitrogen,
toxins, and enhancement of habitat and living resources. In 2003, Horsley Witten Group
(HW) completed a regional stormwater assessment and management project for the
' Peconic Estuary Program that focused on developing a regional, storm-event-based,
pollutant loading model to help prioritize management efforts for four pilot watersheds
within the greater Peconic Estuary system based on the contributions of pathogens and
t nitrogen from each watershed. The Hashamomuck Pond watershed in the Town of
Southold was one of the watersheds studied, and general recommendations were made to
establish remediation and preventive measures for managing stormwater.
' The development of this Watershed Management Plan for the Hashamomuck Pond
watershed is the next phase of that initial project. This plan focuses on improved
' management of stormwater pollutants, including the primary stressors (nitrogen,
phosphorous, suspended solids, and bacteria) and secondary stressors (metals and
hydrocarbons) that are negatively impacting Hashamomuck Pond. In addition, this plan
' identifies important remaining wildlife habitat areas within the Hashamomuck Pond
watershed and provides guidance on which parcels are most valuable for protection of
' critical habitats. The planning process included a rapid field assessment for stormwater
management and habitat value throughout the watershed. The stormwater assessment
was used to identify likely stormwater pollutant sources as well as areas where best
' management practices (BMPs) could be installed to improve the management and
treatment of stormwater in the watershed. Successful implementation of this plan is
expected to help reduce stormwater runoff pollution; maintain or improve overall water
' quality conditions, shellfish harvesting capacity, eelgrass habitat, and degraded marsh
areas; and protect critical open space habitat areas.
' This Watershed Management Plan was developed as a pilot plan, along with three other
pilot plans (West Neck Bay in the Town of Shelter Island, Reeves Bay in the Town of
Southampton, and Meetinghouse Creek in the Town of Riverhead)to serve as a model
for other areas of the Peconic Estuary system. The goal is to eventually develop targeted
management plans by towns and interested groups for small embayments and watersheds
throughout the larger Peconic Estuary system.
The Plan is broken down into five sections and a set of appendices covering the following
major topics: an introduction and review of management objectives; a characterization of
t the watershed; a pollutant loading estimate under build-out conditions in the watershed;
recommendations for improved programmatic stormwater management throughout the
watershed; a detailed stormwater management assessment in which potential sites and
' BMPs are identified and conceptual designs are presented for each recommended site;
and a habitat protection assessment.
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Stormwater Programmatic Assessment and Recommendations ,
An assessment of various stormwater management programmatic opportunities in the '
Hashamomuck Pond watershed was performed. Regular inspections and maintenance are
a top priority to ensure long-term function of the stormwater infrastructure. The review
process for new and redevelopment projects could be improved by adopting a pre- '
approved list of effective BMPs and requiring certain site design techniques to reduce
pollutant loading. In addition, several public education focus areas and programs can
help improve the health of the watershed- outreach campaigns should be tailored to '
target the specific issues in various neighborhoods throughout the watershed including
pet and waterfowl waste, as well as lawn management. Inter-municipal and agency
coordination on these program recommendations can reduce costs and improve '
effectiveness. These programs and recommendations are discussed in more detail in
Section 3.
Stormwater Assessment and Recommendations '
An assessment of stormwater management and treatment in the Hashamomuck Pond '
watershed was performed in order to identify problem areas and potential sites for the
installation of stormwater BMPs. The goal of these BMPs is to improve the removal of
pollutants before the stormwater runoff reaches Hashamomuck Pond. Based on a '
prioritization process, seven locations were selected for BMP implementation.
Stormwater BMPs proposed for these sites include grass channels, bioretention systems,
dry swales, oil/grit separators, micro-bioretention inlets, constructed wetlands and '
sediment forebays. Estimated costs for these BMPs range from$49,000 to $133,000 for
design,permitting, and construction. If all seven proposed BMP retrofits were
implemented, the total cost is estimated at$673,000. The proposed BMPs and the '
methodology used to select locations and practices are described in detail in Section 4. In
addition, assessments are provided that investigate nonpoint pollution sources in the
upland area and recommended actions to improve watershed conditions. These are '
known as "Neighborhood Source Assessments," "Hotspot Site Investigations," "Pervious
Area Assessments," and"Streets and Storm Drains Assessments" and are also discussed
in Section 4. '
Habitat Assessment and Recommendations
The goal of the habitat assessments was to identify parcels of land, or portions of those '
parcels, that exhibited a higher relative ecological value than others. This value is based '
upon readily observable site attributes pertaining to wildlife habitat that could be
observed during a single site visit. Parcels with high ecological value are recommended
for long-term protection through conservation measures or acquisition by the town, a land '
trust, or another similar conservation organization.
Field assessment locations were identified based on data from aerial photographs of the t
watershed and geographic information system(GIS) data layers (e.g. GIS-identified
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' wetland parcels and undeveloped parcels). Sites were selected for on-site review if they
were undeveloped, primarily forested, contained upland areas with residential
' development potential, and were not mapped as "Protected Land"according to
information provided by The Nature Conservancy (TNC) and/or Suffolk County. Once
the rapid field habitat assessment was performed, the areas were prioritized based on
' habitat complexity criteria, level of habitat disturbance, proximity to existing
development and protected area, evidence of ongoing land management activities, and
observable evidence of wildlife.
Three groups of parcels in the Hashamomuck Pond watershed were identified to be the
subject of a field habitat assessment. These included, in order of priority, two contiguous
t parcels of undeveloped coastal land at the end of Long Creek Drive,three adjoining
parcels of land that abut the eastern extent of Hashamomuck Pond, and two large inland
properties between Laurel Avenue and Vennecott Drive. The parcels recommended for
' habitat protection are discussed further in Section 5.
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1.0 INTRODUCTION t
1.1 The Peconic Estuary ,
The Peconic Estuary is located on the eastern end of Long Island,New York between the '
North and South Forks. Its waters cover approximately 158,000 acres with 450 miles of
shoreline and support a wide array of wildlife. There are several smaller bays recognized
throughout the greater Peconic Estuary including Flanders Bay, Great Peconic Bay, '
Shelter Island Sound, Gardiners Bay, and Little Peconic Bay. Bordering this estuary are
the towns of East Hampton, Southampton, Brookhaven, Riverhead, Southold, and Shelter
Island(Figure 1-1). The region is popular for vacationing and supports a wide variety of '
both recreational and natural resources. Boating, swimming and sunbathing are a few of
the many recreational activities that draw thousands of people to this region. Fishing and
shellfishing are two of the predominant local industries that are directly dependent upon '
the water quality of the estuary. Economic studies of the overall Peconic Estuary region
have estimated that those businesses and industries directly tied to the estuary produce
upwards of$450 million of annual income within the region (PEP CCMP, 2001). '
The shellfishing industry in the Peconic region has relied on abundant fisheries resources
to continuously harvest several mollusk species including hard clams (littlenecks, '
cherrystones, and chowders), oysters and scallops. Although all of the 158,000 acres of
bay floor are recognized by state agencies as shellfishing areas, the majority of yield
comes from the shallower rivers and embayments that line the estuary. Estimates have '
varied as to how much of the bay is highly productive with figures ranging from 8,000
acres (Lewis et al., 1997) to 20,880 (PEP CCMP, 2001). The harvesting in these areas is
highly concentrated due to the fact that these beds comprise only six to eighteen percent '
of the entire shellfishing area (Lewis et al., 1997). The clustering of these shellfish in the
smaller embayments demonstrates that estuarine environments with secluded shallower
areas are highly productive. '
The shellfishing beds in the Peconic Estuary have been monitored for several decades by
the New York State Department of Environmental Conservation (NYSDEC) in order to '
assess the safety of these shellfish for consumption. High levels of coliform bacteria
have resulted in the closure, either periodic or year-round, of much of the more
productive beds in the estuary. Coliform bacteria, specifically fecal coliform (FC), are '
produced in the intestinal tracts of warm-blooded animals and are present in high
concentrations in their fecal matter. FC bacteria are used as an indicator for the presence
of other, potentially harmful pathogens. t
Efforts to lower bacterial loading to the Peconics have been ongoing for many years and '
have developed concurrently with federal legislation such as the Clean Water Act
(CWA). In 1987, the CWA was amended to include the National Estuary Program.
Under Section 320, the CWA allows individual States to nominate estuaries for funding '
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toward the development of a CCMP. Once an estuary receives funding from the National
Estuary Program, the CCMP is developed to address the unique environmental needs of
' that specific region. Under the CCMP of the Peconic Estuary Program, activities related
to shellfishing are a primary focus of ongoing research.
' To date, those studies that have investigated the incidence of coliform bacteria in the
Long Island region have concluded that the predominant source of this pollutant is
stormwater runoff(NURP 1983). For this reason, the CCMP prepared by the Peconic
' Estuary Program focuses heavily upon assessing and ultimately eliminating pollutant
loads that result from runoff. One section of the CCMP, the "Pathogens Management
Plan," states that a primary objective is to "maintain the current status of certified
' (seasonally and year-round) shellfish beds and re-open uncertified beds as long as these
do not conflict with the need to protect human health nor with the need to protect and
enhance natural resources" (PEP 2001).
Within the CCMP, non-point source pollution, including stormwater runoff, is given the
highest priority for remedial efforts. Stormwater runoff not only transports potentially
' high levels of bacteria to the bay,but also other pollutants that can be significant
stressors, such as sediments, nutrients, hydrocarbons, and metals. Another specific
priority within the CCMP is limiting nitrogen loading as excessive nitrogen loading can
damage estuarine ecosystems and cause potentially harmful algal blooms. In areas
where lawns and agricultural areas are regularly fertilized, stormwater runoff can deliver
significant amounts of nitrogen to a receiving embayment. A well-designed stormwater
' management plan could therefore reduce several pollutants that potentially contribute to
water quality problems simultaneously. Carefully planned and implemented strategies
t can successfully limit loadings of both FC bacteria and nitrogen. These strategies would
therefore work to help accomplish several of the goals outlined within the Peconic CCMP
including reopening shellfishing areas, reducing overall nitrogen loading, and decreasing
the occurrence of brown tide.
1.2 Project Background
' Horsley Witten Group (HW) completed a regional stormwater assessment and
management project for the PEP in 2003 (Peconic Estuary Stormwater Assessment and
' Planning Tool; hereon referenced as HW, 2003). The goal of the assessment was to
prioritize management efforts for four pilot watersheds within the greater Peconic
Estuary system based on the contributions of pathogens and nitrogen from each
' subwatershed within each pilot watershed, using results from a regional, storm-event-
based,pollutant loading model. The body of information previously compiled for these
four watersheds was used as the starting point and baseline of information for the four
' pilot management plans completed as part of this project. The four pilot watersheds for
which a management plan has been developed are the following:
' • Hashamomuck Pond (Southold), • Reeves Bay(Southampton), and
• West Neck Bay (Shelter Island), • Meetinghouse Creek(Riverhead).
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This Hashamomuck Pond Watershed Management Plan was developed using a rapid '
watershed planning approach, consisting of following three major phases:
1) A watershed assessment stage; '
2)An evaluation of management strategies, including a planning level analysis
of their costs and benefits; and '
3) Recommendations for implementation of management actions.
This plan was developed using previous studies together with aerial photography and a ,
geographic information system (GIS), as well as significant field reconnaissance to
ground truth land use and drainage information, evaluate habitat, identify potential
stormwater pollutant sources, and provide specific management recommendations. A '
significant effort was focused on evaluating management alternatives including structural
best management practices, regulatory and land use changes, and public education. Two
meetings with local watershed stakeholders and information provided by local '
municipalities were integral to the execution of this project.
The main focus of this plan is to improve management of stormwater-derived pollutants that '
are negatively impacting Hashamomuck Pond by both effectively addressing pollution
prevention and implementing a variety of appropriate stormwater best management practices
(BMPs)in key areas. In addition,this plan identifies important remaining wildlife habitat '
areas within the Hashamomuck Pond watershed and provides guidance on which parcels are
most valuable for protection of critical habitats. The planning process included a rapid field
assessment for stormwater management and habitat value throughout the watershed. The '
following goals of the Peconic Estuary CCMP will be at least partially achieved through the
successful implementation of this watershed management plan.
For Pathogens: '
• Maintain current level of lands available to shellfish harvesting and re-open '
closed shellfish beds;
• Reduce overall stormwater runoff pollution; and ,
• Attain a zero discharge of untreated stormwater runoff from new development.
For Nitrogen: ,
• Decrease total nitrogen concentration in the western estuary to 0.45 mg/L;
• Ensure that total nitrogen levels in shallow waters remain at or below 0.4 mg/L in '
order to maintain and improve eelgrass habitat;
• Improve or maintain existing total nitrogen levels in Flanders Bay;
• Develop a nitrogen allocation strategy for the entire estuary, with an initial goal to '
reduce fertilizer nitrogen loading by 10-25%;
• Ensure that there is no substantial net increase in nitrogen loading to areas east of
Flanders Bay; and '
• Continue to acquire open space.
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For Habitat and Living Resources:
' • Protect the high quality habitats in Critical Natural Resource Areas;
• Maintain current eelgrass acreage and increase acreage by 10% over 10 years;
' • Maintain and increase tidal and freshwater marsh acreage, restore degraded areas;
and
• Enhance shellfish resources.
' For Toxins:
' • Improve the quality of the ambient environment where there is evidence that
human inputs of toxins impair or threaten these resources;
' • Comply with hazardous waste disposal and remediation regulations;
• Decrease overall emission of toxins;
• Eliminate holdings of banned pesticides and hazardous substances;
• Decrease overall pesticide applications in the five east end towns; and
• Eliminate, to the maximum extent possible,pesticide applications on turf grass on
all publicly held land.
' 1.3 Organization of the Plan
' This Watershed Management Plan is broken down into five sections and a set of
appendices. Section 2 depicts a characterization of the watershed including a land use
assessment, a pollutant loading assessment, a discussion of the existing local review
process for land development in the watershed, a discussion of the existing stormwater
infrastructure, and a pollutant loading estimate under build-out conditions in the
watershed. Section 3 presents recommendations for improved programmatic stormwater
' management throughout the watershed. These recommendations cover suggested
modifications to the existing land development review process,possible improvements
for maintenance of stormwater infrastructure, and improved stormwater management
' public education. This is followed in Section 4 by a subwatershed-specific stormwater
management assessment in which potential sites and best management practices are
identified, and conceptual designs are presented for each recommended site. Section 4
' also includes assessments provided to quantify impacts from land uses with high
pollutant loading potential(known as "hotspots") and the drainage systems themselves.
These are known as"Neighborhood Source Assessments," ..Hotspot Site Investigations,"
' "Pervious Area Assessments," and"Streets and Storm Drains Assessments." These
assessments were all performed in the field to identify other opportunities to improve
' watershed conditions, target outreach efforts, and reduce pollutant loads. In addition, a
stormwater management site ranking system is presented, and the field reconnaissance
methods are described. Section 5 presents habitat protection sites and methods used to
' identify and rank them. The appendices include the methodologies, the stormwater
retrofit conceptual plans, the stormwater field data sheets, and the habitat field data
sheets.
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2.0 WATERSHED CHARACTERISTICS ,
2.1 Land Use Watershed Characterization
Hashamomuck Pond is a secluded embayment located in Southold along the North Fork '
of Eastern Long Island(Figure 2-1). The embayment is approximately one mile long and ,
one-quarter mile across at its widest point. At the northwestern end of the embayment, a
slender extension called Long Creek tapers off the main body of the embayment. The
embayment narrows and connects with Peconic Bay at its southern most point through '
Mill Creek. The tidal range within Hashamomuck Pond is approximately three feet with
the surface water covering approximately 170 acres. The watershed contributing to
Hashamomuck Pond is mostly residential with a large area of open field under succession '
and vegetable cropland in the northwest quadrant of the watershed (Table 2-1 and Figure
2-2). The southern shore of the pond near the outlet to Shelter Island Sound is primarily
vacant scrubland and the northern shore near the outlet is agricultural land. The shoreline ,
of Hashamomuck Pond is bordered mostly by low and medium density residential
housing. Most houses within the watershed around Hashamomuck Pond have on-site
septic systems and there are no sewage treatment systems discharging directly into the ,
Pond.
Table 2-1. Hashamomuck Pond Watershed Existing Land Use Summary '
Land Use Category West Neck Area West Neck Area
(Ac) % of Total '
Low Density Residential 33.7 800
Medium Density Residential 77.4 18% ,
High Density Residential 4.3 1%
Commercial 5.1 1% '
Industrial 0.0 0%
Institutional 0.8 0%
Open Space 192.4 44% ,
Agriculture 93.1 22%
Vacant 0.0 0% '
Transportation 25.6 6%
The New York State Department of Environmental Conservation (NYSDEC) has ,
designated this embayment as "growing area 23"and has monitored its water quality with
varying frequency for several decades. All of the waters within Hashamomuck Pond '
experience some level of closure due to unacceptable levels of bacteria. The most
secluded areas in the northeastern corner, includingalmost all of Lon Creek are closed
g
year-round. Adjacent to these areas is a section of the embayment that is under a '
conditional program where certification is dependent upon the results of more rigorous
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' sampling. The main body of Hashamomuck Pond can be seasonally certified for
shellfishing between December 1 and April 30. From December 21, 2005 through April
' 30, 2006, the waters of Hashamomuck Pond normally designated as closed were
classified as conditionally certified, with the exception of the Clay Pit (the enclosed
pond). This conditional designation is not automatic and is established on an annual
' basis. Conditional areas remain open to shellfishing provided that not more that 0.35
inches of rainfall is recorded in a 24-hour period. Pursuant to federal and state
regulations,bacteriological sampling and pollutant source surveys are performed
' annually for those areas that are seasonally and conditionally closed.
Hashamomuck Pond(Priority Waterbodies List#1701-0162) is one of twenty
' waterbodies within the Peconic Estuary for which a Pathogen Total Maximum Daily
Load(TMDL) is being developed by the USEPA and NYSDEC. A TMDL is a
regulatory apportionment of loading that frequently requires a reduction goal for each
' pathogen point and nonpoint source entering the Peconics. Nonpoint sources,
particularly stormwater runoff containing waterfowl, wildlife, domestic pet, and livestock
waste, as well as direct deposition of waterfowl waste, are the most significant
' contributors of pathogens to the Peconics. The basis for the TMDL analysis lies within
New York's 303(d) list of water segments that exhibit impaired conditions.
' The majority of soils surrounding the pond are highly permeable type "A" and type `B"
soils (Figure 2-3). Hydrologic soil groups are used to generally group different soil types
' based upon their relative ability to infiltrate versus runoff water. "A" soils are the most
permeable and generate the least amount of stormwater runoff while"D"soils are the least
permeable and generate the most runoff. Type "C" soils occur in the Hashamomuck Pond
watershed mostly in areas where road construction has used artificial fill. Type "D" soils
are found in isolated areas that are predominately muck and tidal marsh. These small
areas will provide significantly higher levels of runoff per unit of area than the wider
' coverages of type "A" and type"B" soils.
2.2 Pollutant Loading Assessment
' In our initial study(HW, 2003), pollutant loading potential was evaluated under existing
conditions in order to help prioritize areas generating higher pollutant loads and to target
' future management recommendations. That evaluation was conducted using an
interactive model to perform two fundamental calculations: runoff volume and total
pollutant load by watershed(HW, 2003). The overall watershed to the embayment was
' divided into even smaller subwatershed areas for assessment based on a field survey
performed by the Peconic Baykeeper. The volume of runoff is calculated in the model
using the U.S. Department of Agriculture -Natural Resource Conservation Service
' (USDA-NRCS) TR-55 method. To determine the total pollutant load, this volume is then
multiplied by a series of FC bacteria and nitrogen loading coefficients. Each coefficient
is expressed as a concentration of the specified pollutant within a fixed amount of runoff
' that is specific to the land use categories listed in Table 2-1.
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♦
r
_.♦ _ c+♦,`"`spa �` � Q 11 ; �i�\'
to o
Oa' _
rr♦ice ♦\\� i �.� '.
le I
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r
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Legend
T iul ��le( rt4i eli Un II I
9 Hydrologic Soil Groups Ie
Subwatershed
Boundaries q
N Hydrologic Soil Groups within
BA
Hashamomuck Pond
- c Watershed
- D 0 1100 Feet J.W44 Pe is Bay Estuaryvepads\
arts Figure 2-3
Haahamrau&P
Currently, there are no available runoff sampling data for any of the subwatersheds
contributing runoff to Hashamomuck Pond. As a result, HW designed the preliminary
' bacteria model to provide results for a range of loading values taken from scientific
literature and sampling in other areas of Long Island. The values available to the user are
a minimum, maximum and average value adapted from this research. Research in the
area of nitrogen loading coefficients reveals a much more consistent set of values in the
literature. As a result, it was not necessary to model a range of nitrogen loading
coefficients.
' Loading calculations were performed for the Hashamomuck Pond watershed using three
target storm events: the 0.25-inch, 0.6-inch and 1.3-inch. The 0.25-inch storm was
chosen to potentially isolate the first-flush effect where pollutants are preferentially
concentrated in the initial flush of runoff; the 0.6-inch rain event was chosen as the mean
of the precipitation data set recorded by NYSDEC in conjunction with their water quality
' sampling, and the 1.3-inch storm was chosen as the approximate 90`b percentile
precipitation event, since approximately 90% of the precipitation events, according to
NYSDEC data, fall below 1.3 inches. The resulting average concentration in the
embayment was calculated assuming a mean low tide depth of 5 feet, a tidal range of 3
feet, and a waterfowl population of 51. A summary of the results for the 0.6-inch
' precipitation event is provided below in Tables 2-2 and 2-3. A more detailed description
of the loading model and associated assumptions can be found in HW's initial stormwater
assessment for the Peconic Estuary (HW, 2003). Modeling results in the 2003 report are
' different than those presented here because field reconnaissance after the 2003 study led
to the modification of some watershed boundaries, and the way the model characterized
land use for some large parcels. A number of large parcels are zoned for higher density
' residential occupancy than is currently occurring. In the current version of the model for
existing conditions, those parcels are treated as open space (which the majority of the
parcel areas actually are) rather than as zoned residential land use.
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Table 2-2. Summary of GIS-Based Bacteria and Nitrogen Loading Model for ,
Hashamomuck Pond Under Existing Conditions for the Mean, 0.6-Inch
Precipitation Event
Subwatershed Modified Runoff Bacteria Load Nitrogen Load '
Curve Volume (millions oforgs) (pounds)
Number* liters '
1 78 1,381 290 0.00
2 81 6,065 1,280 0.02
3 79 4,749 1,000 0.02 '
4 83 23,149 5,100 0.10
5 98 29,438 16,130 0.27
6 81 714 170 0.00 '
7 86 35,443 9,860 0.17
8 86 4,692 1,170 0.02 '
9 78 3,378 770 0.01
10 92 801,534 109,820 5.91
11 87 143,117 19,370 0.90 '
12 85 125,872 36,100 0.65
13 86 137,771 17,480 0.86
14 89 41,865 6,020 0.18 ,
15 87 29,800 7,870 0.14
16 87 33,221 7,450 0.14
17 85 27,308 7,890 0.13 '
18 87 45,921 12,480 0.22
19 90 639,323 88,330 3.98
20 77 0 0 0 '
21 76 0 0 0
22 90 69,660 23,400 0.40
23 84 7,175 1,660 0.03 '
24 78 92 20 0
Total 274,006 145,580
*Modified for small storm hydrology based on research and methodology by Pitt(1987)as descr bed in the
Peconic Estuary Stormwater Assessment and Planning Tool(HW,2003).
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Table 2-3. Comparison of Average Embayment Concentrations Predicted by the
' Model Under Existing Conditions with Measured Concentrations in
Hashamomuck Pond
' Range of Geometric Modeled Modeled Modeled
Wet Weather Mean of Wet Concentration Concentration Concentration
Measurements Weather from Minimum from Average from Maximum
' Measurements Coefficients* Coefficients* Coefficients*
or s/100 mL or s/100 mL or s/100 mL or s/100 mL or s/100 mL
2.9-2,501 34 2.5 26.6 50.7
orgs=Number of Organisms
mL = Milliliters (1x10'Liters)
*Coefficients based on the minimum,average and maximum values found in literature review.
' 2.3 Existing Land Development Review Process
Proposed development of land in the Town of Southold is governed by the Code of the
' Town of Southold,New York(the Code),which includes provisions regulating the
subdivision of land, development within flood hazard areas, and development or
alteration within wetlands or within 100 feet a wetland. In addition, specific types of
' development projects that are designated Type I projects under the NY State
Environmental Quality Review Act (SEQRA) are required to go through an
environmental quality review process. These land development requirements of the
' Town of Southold are described in more detail below.
Projects involving the subdivision of land must seek permit approval by the town
Planning Board. There is no differentiation between minor and major subdivisions in the
Southold Code. The first step in preparing a subdivision submittal is the preparation of
an existing resources and site analysis plan (ERSAP). Wetlands and waterways within
' the subdivision plan must be shown on the ERSAP, along with flood-prone area, aquifer
recharge areas, soils, viewsheds and other resource areas. All proposed subdivisions are
then required to follow the primary and secondary conservation area design process,
which includes developing a Sketch map by first placing houses on the ERSAP base map
with the goal of avoiding conservation areas, and then placing roads and driveways in
accordance with design standards to connect the houses. Stormwater must be maintained
' onsite within the subdivision, and all historic drainage patterns must be preserved on a
subdivision site. Once the Planning Board approves that plan, the preliminary and then
final plat plans are submitted. Drainage plans, details and design calculations must be
submitted in both of submittal stages for review by the Planning Board and Engineering
Department, which will review the plans to ensure compliance with the Highway
Specifications of the local code. Final road and drainage plans are required to be bonded
' until completion. Erosion and sedimentation controls are required during construction.
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Site Plan Approval under the Zoning Code is required for all projects, except for single- ,
family residential homes and accessory uses on a single and separate lot. This approval
process is handled through the Building Inspector, who calls upon the Planning Board for '
comments. Site plan submittals must include general grading and drainage information,
and stormwater must be retained on-site, in conformance with the Southold Highway
Specifications in the local code. '
Wetlands are protected from adverse impacts of alteration through the Wetlands Law of
the Town of Southold, which requires a permit for work generally within 50 feet, or ,
sometimes up to 100 feet of a wetland, depending upon the type of wetland and activity.
This process is implemented by the Board of Trustees. Permits may include stormwater
upgrades on an existing site in order to ensure that all stormwater from a 2-inch rainstorm '
is maintained on the site. Certain limited projects listed in the local law that are expected
to have minimal impact of the adjacent wetland can be approved through a simpler
administrative permit process. ,
Projects requiring construction in the flood hazard areas, as mapped by FEMA on the
Flood Insurance Rate Maps for Southold, require a floodplain development permit, the '
purpose of which is to protect human health and welfare, and property. Applications are
reviewed and projects are monitored by the building inspector.
In accordance with the Code and SEQRA, certain projects must complete an ,
Environmental Quality Review process. Projects that fall into the category of Type I
actions are required to file an Environmental Impact Statement(EIS). ,
There is currently no specific land development control mechanism that would require a
project proponent to assess or mitigate for potential nitrogen loading from stormwater ,
runoff from a proposed project. However, revegetation of a buffer area to a wetland must
be with native vegetation and without the use of fertilizers and pesticides. It is widely
accepted that sources of nitrogen on a site may include septic systems, fertilizers on '
lawns, stormwater runoff, domesticated animals, or wildlife. Traditional on-site septic
systems, even those sited properly according to code, still contribute nitrogen to the ,
groundwater and, ultimately, to Hashamomuck Pond.
2.4 Existing Stormwater Infrastructure and Maintenance
The existing municipal stormwater infrastructure in the Hashamomuck Pond watershed '
includes deep sump and leaching catch basins,roadside drainage ditches and swales, and '
detention and infiltration basins. The Southold Highway Department is responsible for
maintaining the municipal stormwater infrastructure. There is no set schedule for regular
stormwater maintenance but when there is a drainage problem, the Highway Department ,
addresses it on an individual basis. Every road is swept at least once per year, starting in
the spring after the last snowfall. The town Highway Department noted that there are
many stormwater improvement projects currently being performed throughout the town. '
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' Private land owners are responsible for the inspection and maintenance of their own on-
site stormwater management.
2.5 Pollutant Loading Assessment—Future, Buildout Conditions
' The model developed for HW's initial stormwater assessment for the Peconic Estuary
Program (HW, 2003) used the most current available GIS-based land use data. These
model results therefore provide an estimate of pollutant loading to the embayment under
' existing conditions. As part of continued assessment of Hashamomuck Pond, HW
developed an approach to examine potential changes in land use patterns based on
applicable local regulations. The original nitrogen and fecal coliform bacteria loading
' model runs were updated to include estimates for future land development. Using the
2001 Suffolk County Land Use database as the foundation for this exercise, HW used
two essential pieces of information to update the model. First, local Zoning Codes were
' consulted to determine the allowable uses throughout each watershed and the minimum
lot sizes associated with these uses. Second, HW used wetland coverages from 1994 in
conjunction with aerial imagery to determine the extent of wetlands on zoned buildable
areas. The following assumptions were employed to determine buildout conditions.
' 1. Wetland coverages were used to eliminate portions of existing parcels that are
undevelopable.
2. Minimum lot sizes from existing Zoning Codes were used to eliminate non-
conforming undeveloped parcels from the future use analysis.
3. Areas identified as "open space"by the Suffolk county land use database are
protected as open space and therefore not developable in the future.
' 4. Remaining areas of existing "Agriculture"were identified that show potential for
development. These areas were cross-referenced with the Suffolk County
Planning Department's 2001 Land Available for Development, Long Island Sound
Study, Suffolk County North Shore Watershed Management Program.
5. Existing aerial photography was reviewed to identify any existing features or
structures that show the land as already developed. This portion of the analysis
' also included a qualitative assessment of whether a parcel is reasonably
accessible.
After this five-step process,the remaining Agriculture use in each watershed was
assumed to be developable. According to the existing Zoning Codes, the land use codes
of these developable tracts were changed to their most likely future use, and the model
' was run again. Where significant tracts of wetland covered a portion of a developable
lot, these areas were omitted from the future development profile.
Under buildout conditions, the Hashamomuck Pond watershed is projected to be a mix of
low and medium density residential development and open space. Although agriculture
makes up a significant portion of the watershed under existing conditions, most of these
' areas could potentially to be converted to low density residential development.
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Table 24. Future Change in Land Use-Hashamomuck Pond Watershed '
Land Use Category Existing Area Future Area Percent
' (Ac) (Ac) Change '
Low Density Residential 33.7 121.1 259%
Medium Density Residential 77.4 77.4 0% '
High Density Residential 4.3 4.3 0%
Commercial 5.1 5.1 0% '
Industrial 0.0 0.0 0%
Institutional 0.8 0.8 0%
Open Space 192.4 197.5 3% '
Agriculture 93.1 0.5 -99%
Vacant 0.0 0.0 0% '
Transportation 25.6 25.6 0%
Future loading calculations were performed for the Hashamomuck Pond watershed also '
using the three target storm events. Similar to the original parameters, the resulting
average concentration in the embayment was calculated assuming a mean low tide depth '
of five feet, a tidal range of three feet, and a waterfowl population of 51. A summary of
the results for the 0.6-inch rain event is provided below in Table 2-5. Several of the
subwatersheds demonstrated significant decreases in both bacteria loading and nitrogen '
loading. This is the result of agricultural lands being converted to low density residential
development, since agricultural lands supply more runoff, bacterial loading and nitrogen
loading than low density residential development. '
Table 2-5. Summary of GIS-Based Future Bacteria and Nitrogen Loading Model
for Hashamomuck Pond for the Mean 0.6-Inch Precipitation Event '
Subwatershed Modified Runoff Bacteria Increase in Nitrogen Increase in
Curve Volume Load Bacteria Load Nitrogen
Number (liters) (millions Load from (pounds) Load from ,
of orgs) Existing Existing
(millions of (pounds)
ors) '1 78 1,381 290 0 0.00 0
2 81 6,065 1 1,280 0 0.02 0
3 79 4,749 1 1,000 0 0.02 0 '
4 83 23,149 5,100 0 0.10 0
5 98 29,438 16,130 0 0.27 0
6 81 714 170 0 0.00 0
7 86 35,443 9,860 0 0.17 0
8 86 4,692 1,170 0 0.02 0
9 77 0 0 -771 0.00 -0.01 '
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Subwatershed Modified Runoff Bacteria Increase in Nitrogen Increase in
Curve Volume Load Bacteria Load Nitrogen
Number (liters) (millions Load from (pounds) Load from
of orgs) Existing Existing
(millions of (pounds)
' or s
10 85 168,375 40,040 -69,778 0.79 -5.12
11 82 28,448 6,200 -13,177 0.12 -0.78
12 85 125,850 36,100 -5 0.65 0
13 81 21,415 4,540 -12,933 0.09 -0.78
' 14 89 41,865 6,020 0 0.18 0
15 87 29,800 7,87 1 0 0.14 0
16 87 33,221 7,450 1 0 0.14 0
' 17 85 27,308 7,890 0 0.13 0
18 87 45,921 12,480 0 0.22 0
19 84 181,575 39,700 -48,632 0.73 -3.25
' 20 77 0 0 0 0.00 0
21 76 0 0 0 0.00 0
22 90 69,660 23,400 0 0.40 0
' 23 84 7,175 1,660 0 0.03 0
24 78 92 1 20 1 0 0.00 0
' As part of the modeling of both existing and future conditions, HW identified the three
subwatersheds that contributed the highest levels of pollution. Figure 2-4 illustrates the
highest contributors of fecal coliform bacteria for both existing and future conditions.
' Under existing conditions, subwatersheds 10 and 19 together contribute more than half of
the fecal coliform loading for the entire watershed. Subwatersheds 10, 12 and 19 will
continue to be the highest contributors of fecal coliform loading under buildout
conditions, although it is estimated that the loading will be more even distributed
amongst the subwatersheds.
' Under existing conditions, subwatersheds 10 and 19 also contribute the most nitrogen,
together providing approximately 70% of the total watershed nitrogen loading(Figure 2-
5). Buildout conditions provide the same scenario for nitrogen as they did for fecal
coliform bacteria,with subwatersheds 10, 19, and 12 being the highest contributors of
nitrogen at 19%, 17% and 15% of the total nitrogen loading for the Hashamomuck Pond
watershed.
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Figure 2-4. Hashamomuck Pond watershed—highest priority subwatersheds for ,
fecal coliform loading under existing and future conditions.
Existing Conditions Future Conditions '
M 29'/0 of total FC loading M 18%of total FC loading '
M 24%of total FC loading M 17%of total FC loading
M 10%of total FC loading M 16%of total FC loading
12 19 12 19 '
10 10 '
1
*The subwatershed numbers for those subwatersheds contributing the highest estimated '
pollutant loading are labeled in the diagram above.
Figure 2-5. Hashamomuck Pond watershed—highest priority subwatersheds for '
nitrogen loading under existing and future conditions.
1
Existing Conditions Future Conditions
42%of total Nitrogen loading 199/6 of total Nitrogen loading '
28%of total Nitrogen loading 17%of total Nitrogen loading
6%of trial Nitrogen loading 15%of total Nitrogen loading '
19 12 19
Of11
10 10 '
14
*The subwatershed numbers for those subwatersheds contributing the highest estimated
pollutant loading are labeled in the diagram above. '
In order to control potential future loading from Subwatersheds 10, 12, and 19, it is
recommended that stormwater management controls be employed that allow for '
enhanced nitrogen and bacterial removals. Infiltration of stormwater runoff(with pre-
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' treatment) from all impervious and pervious surfaces, buffers between lawns and water
resources, and other best management practices (BMPs) described further in sections 3
' and 4 that remove 50% of the total nitrogen and 90% of the fecal coliform can reduce
future loads accordingly.
1
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3.0 STORMWATER MANAGEMENT PROGRAMMATIC OPPORTUNITIES ,
3.1 Recommendations for Modifications to Land Development Review Process '
The land development review process can be improved to reduce potential impacts to the
water quality in the Pond by implementing the use of comprehensive and uniform '
stormwater standards for new development and redevelopment. These standards can be
revised to include explicit stormwater treatment requirements to reduce nutrient loading
as well as suspended solids, bacteria and other toxics to the groundwater and the Pond, as '
well as to improve erosion control. The Planning Board could use this set of standards as
a uniform reference to improve consistency in stormwater design and management
throughout the Peconic region. These standards could be incorporated directly into the '
language of the subdivision regulations or as a separate policy document that can be
referenced by the subdivision regulations. This second option allows more flexibility to
update the policy as technologies advance and conditions change, without having to '
formally update the subdivision regulations.
The standards could include a pre-approved list of appropriate stormwater best '
management practices, along with design guidelines for proper siting, sizing, installation
and maintenance of the practices. As a starting point, specific sections of The New York
State Stormwater Management Design Manual (NYS DEC,August 2003) should be '
referenced as the general reference for stormwater design. This manual provides a set of
stormwater practices, sizing criteria and performance criteria, and describes in detail the
proper design, limitations, and effectiveness of a host of practices. Those practices that ,
are more effective than others for nitrogen and bacteria removal (e.g., bioretention and
constructed wetlands are better than swales) should be promoted or required by the town
versus the use of other practices. For example, some research studies have shown that '
catch basin inserts (proprietary BMPs gaining popularity in some areas due to easy and
low-cost installation) have low removal rates for nitrogen, high maintenance burdens for
communities, and should be implemented sparingly. Catch basin inserts also have not
been sufficiently studied to estimate bacteria removal,but their operation characteristics
are such that it is highly unlikely that bacteria will be reduced at significant levels. See
Appendix A for more details and some references for these findings. BMPs with high '
nitrogen and bacteria removal capabilities that should be promoted include constructed
wetlands, bioretention facilities, organic/sand filters, and infiltration practices.
The New York manual also provides useful landscaping and site layout techniques to '
reduce pollutant loading to receiving waters,which may be useful to include in the
town's list of practices and standards. These site layout techniques include buffer '
standards for separating development from surface waters. Buffers are effective for
controlling nitrogen-containing runoff from turf areas as well as discouraging nuisance '
geese populations.
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1 Recommendations:
' • Adopt a short, pre-approved list of BMPs effective at nitrogen and bacteria
removal.
• Require appropriate landscaping and site layout techniques.
' 3.2 Recommendations for Maintenance of Stormwater Infrastructure
' In the Town of Southold, ownership of stormwater infrastructure is shared by the Town
and individual landowners. Roadway drainage is collected into a municipal infrastructure
that generally terminates with infiltration into the groundwater through leaching catch
basins and infiltration basins, as well as direct discharges in some cases. When a new
subdivision road is constructed and accepted by the Town, the responsibility for the
' drainage infrastructure also passes to the Town. The drainage infrastructure that collects
and treats stormwater on each individual lot is the responsibility of the landowner to
inspect and maintain.
' In order to function as designed over the long term, stormwater infrastructure must be
maintained regularly. This is particularly important with structures designed for
' infiltration, such as leaching catch basins, which may receive stormwater that has not
been pre-treated and therefore contains oils, greases, organic matter, and suspended
sediment that can clog the system. Depending on the land use, inadequate pretreatment
' may allow for dissolved pollutants to enter groundwater and lead to both health and
environmental threats. On individual properties, runoff from rooftops and driveways that
is not properly infiltrated into dry wells or other onsite structures could back up into
basements, cause nuisance puddling, and in some cases, lead to surface discharges and
erosion rather than infiltration.
' The following is a set of recommendations to improve the system by which maintenance
is performed, and ensured, on stormwater practices and infrastructure in the
Hashamomuck Pond watershed and the Town of Southold.
' Recommendations:
t • Implement a formal municipal stormwater inspection and maintenance schedule
for municipally-owned stormwater infrastructure. Regular inspections should be
performed twice per year, once in the early spring, prior to the spring rains but
' after the winter snow melt,which transport winter sands and salts form the roads,
and once in the fall after the large release of organic matter such as leaves and
debris. Cleanouts of leaching catch basins and other sedimentation practices are
' recommended to be performed every year, but at a minimum of every 2-3 years,
and on an additional as-needed basis. This will help reduce clogging of
infiltration devices and sediment transport through scouring and resuspension
' during larger spring rains.
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• Maintain a `working' map of all municipally-owned stormwater practices. If ,
maintained in a GIS or other database, the database can also be used to track when
maintenance was performed, and to document when certain structures '
experienced problems.
• Implement a formal highway and engineering department review and approval '
processes of all stormwater management designs for subdivisions and site plan
review projects against a set of clearly defined design standards. This will
provide consistency and among designs,bring designs up to a minimum state-of- '
the-art standard, and provide applicants with a design guidance. The highway and
engineering departments also should formally review and approve all operations
and maintenance plans for subdivisions that are planned for acceptance by the '
Town, and then adopt those plans into their regular inspection and maintenance
schedule.
• Develop a brief Landowner's Guide for Maintenance of Stormwater Structures. ,
This guide could focus on inspection and maintenance of on-lot stormwater
practices for both residential and commercial/industrial sites. It can also describe '
things that local landowners can do to assist the Town in maintaining public
infrastructure, such as cleaning off debris from around nearby catch basins and
reporting stormwater infrastructure malfunctions and flooding problems. '
3.3 Public Education and Outreach—Recommended Focus Areas
An education and outreach campaign can be used to target specific audiences to try to ,
positively influence human behaviors in the watershed with potential ecologic impact. At '
the same time, the program can reach out to a broad audience to raise awareness that land
use and human activity within the watershed has a direct effect on the health and quality
of the coastal resources. The theory is that if people understand the connection between '
their individual activities and the coastal resource, they will be more apt to alter their
behavior. Many of the behaviors assessed during the field inventories discussed in
Section 4 (Neighborhood Source Assessment, Streets and Storm Drain Assessment, and
Hot Spot Inventory) can be positively influenced by public education. The key public ,
education issues in the Peconic watersheds that will help address the key goals of the
CCMP (see Chapter 1) are: '
• waterfowl management;
• lawn management;
• pet waste management;
• stormwater management; and
• septic system maintenance. '
These focus areas are described below, followed by a description of recommended
education and outreach programming techniques. These techniques are intended to be a '
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' menu of possible strategies that can be employed in various combinations depending on
time, budget and target watershed audience.
' 3.3.1 Waterfowl Management
There are a handful of methods that are used in various situations to reduce the
populations of waterfowl in and around a waterbody, thereby reducing nutrient and
bacteria loads to that area. These include habitat modification, frightening, exclusion,
discontinuation of feeding, live capture, hunting, and egg addling. Some of these
' methods require changes in practices by the landowners in the area, and some require
professional or third-parry assistance. For example, habitat modification refers to the
modification of large expanses of open grassed areas that are often mowed directly to the
water's edge. These areas are attractive to waterfowl such as geese, swans and ducks that
like to have a clear sight line and open access to the water. Modifying these open spaces
to allow for a vegetated buffer along the water edge makes the area much less attractive
' to these waterfowl. A 50-foot vegetated buffer, with vegetation growth up to 3-4 feet
high, makes a large impact in deterring geese and swans by breaking up the open lawn
space from the open water. Creation of this buffer, however, often depends on the will of
' the land owner to convert mowed area to vegetated area. This is where public education
comes into play.
Public education implementation tools include: mailers, television and radio
advertisements, newspaper articles and signage. One common public education method
is the implementation of a demonstration project. If there are publicly owned properties
along the waterfront, or areas owned by a willing owner, a buffer area of open mowed
lawn could be allowed to revegetate, forming at least a 50-foot wide buffer along the
' water's edge. Photographs and information about the former presence of waterfowl and
depicting the look of the former vegetation versus the revegetated area relays important
information to a wider audience about both the goal of the program as well as something
that they can visualize. Signage describing the area as a waterfowl management buffer
could be placed in public view, and then an explanation of the site could be presented in
mailers or brochures for others to see. Often it is easier for people to implement
something once they know what it will look like, and they can have reasonable
expectations about whether it will be effective.
An added bonus from allowing mowed and manicured lawn areas to revegetate is that
maintenance is significantly lower and less fertilizer or other lawn chemicals would be
used. This leads into the next area of focus for public education in the Peconic region,
which is lawn management.
Other methods of waterfowl management include live capture of the birds, egg addling,
and hunting. Egg addling is a method used to control the hatching of eggs. The eggs in a
nest are shaken, making them nonviable, and then replaced in the nest. These methods
require permits from the US Fish and Wildlife Service and may require state or local
' permits as well. In some cases, these methods may face local opposition; but in severe
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situations of uncontrolled waterfowl populations, a local municipality may opt for these '
more direct methods.
3.3.2 Lawn Management '
Many Peconic area lawns are maintained over the majority of the available lot area,
irrigated with potable water, and treated with fertilizers and herbicides. Some lawns '
consist of non-native grasses. Public education can be used to help change these
practices and teach homeowners about alternative lawn care practices. Smaller lawns are
easier to maintain and allow room for larger more diverse and colorful vegetation. The '
use of native grasses and compost folded into the soil can reduce the need for additional
pesticides and herbicides and will provide a more drought-resistant groundcover, which
will in turn require less irrigation. In cases where irrigation is still required or preferred, '
the homeowner can use a variety of methods to reduce irrigation demand, including rain
barrels or cisterns to catch rooftop runoff for irrigation, or programmed irrigation systems
to water their lawns only during early morning or late evening hours. ,
Providing this guidance to homeowners and other landowners within the watersheds
requires an effective public outreach plan. This can be done through a media campaign, ,
which could be a combined effort with the other focus areas. It could also benefit from a
demonstration project site that would show other homeowners what a smaller, more
natural lawn and yard with more diverse landscaping can look like. A demonstration site '
could be a mechanism to provide information about cost savings and time savings due to
lower maintenance requirements, and to collect information about any increase in song
birds, decrease in nuisance species, etc. '
There are several example programs in the northeast that promote healthy and sustainable
lawn management. The Rhode Island Cooperative Extension GreenShare Program '
(http://www.uri.edu/ce/ceec/greenshare.html) and the URI Nonpoint Education for
Municipal Officials (MEMO) Healthy Landscapes program
(http://www.uri.edu/ce/healtbylandscapes/index.html ) provide guidance on sustainable
gardening and lawn maintenance to promote the use of native vegetation that is suitable
for the soil and site conditions. '
A program such as the Bayscapes Program in the Chesapeake Bay Watershed is a good
example. This program provides guidance to homeowners and landowners within the '
Chesapeake Bay Watershed about developing and installing`Bayscapes," which are
landscapes other than turf that are elected to reduce irrigation demand, improve habitat,
reduce non-point pollution, and reduce erosion, while also appealing to gardeners. This '
program uses a website (http://www.fws.gov/chesapeakebay/bayscapes.htm), fact sheets
and examples to provide information.
In Westchester County,New York, the Grassroots Healthy Lawn Program was an '
initiative of the county government and a non-profit organization called Grassroots
Environmental Education, based in Port Washington on Long Island. The goal of this ,
initiative was to promote healthy lawn management by reducing the use of pesticides and
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' other toxins on lawns throughout the county. The program provided training to
landscapers, provided public outreach services, served as a liaison between manufacturers
and retailers, and developed a list of natural lawn care product suppliers for public
distribution (http://www.ghlp.org/).
3.3.3 Pet Waste Management
Pet waste can be a nuisance to the public in addition to contributing bacteria and nutrients
to a water body when it gets washed off the ground surface by rain fall and stormwater
' runoff. For those people that have pets,picking up after your dog can also be a nuisance.
However,more and more people are realizing the aesthetic and environmental health
benefits of cleaning up pet waste from public areas and their own back yards, and in
many communities throughout the country now there are "pooper-scooper" laws
requiring people to clean up. While the idea of picking up after your dog may seem
absurd at first, a few pooper-scooper signs, some pooper scooper bags, and the risk of
being seen not picking up after your dog can go a long way. A media campaign can
easily be created with a sense of humor to get the message across, and signage at public
open spaces and along walking trails can bolster the message. Once the signage is up,
people can learn a new message.
3.3.4 Stormwater Management
' Homeowners and the general public in a watershed can play an important role in looking
after the systems on a day-to-day basis. This is particularly true in subdivision settings,
' where the stormwater management practices may be slightly off the beaten track for the
local Public Works Department and where some small stormwater management practices
may be dispersed throughout the subdivision or even on individual lots. After all, a
failure in the stormwater management system could mean a flooding situation or could
create a sedimentation problem at the discharge location that directly affects local
residents.
' A stormwater awareness program developed and implemented through the local
municipality can be a very useful tool in promoting effective and sustainable stormwater
' management. Mailings and inserts with local billings and other municipal
communications to residents can raise awareness and inspire vigilance among local
residents. Residents can help to monitor swales, leaching systems, catch basins and
' discharge locations to see that they are functioning properly. They can act as a first
defense against failures and can report problems to the public works department. In the
fall,residents can help by clearing leaves and debris from the catch basin grates and by
not throwing leaves and debris into drainage swales, onto roadways, or into other
stormwater pathways. In the winter,the same goes for snow that is shoveled and plowed
off driveways and sidewalks. They can also help by not washing vehicles excessively
often, which can use large volumes of potable water, and by not washing them in their
driveways, which can contribute phosphorus from the soap into the stormdrain system.
Instead, residents should use modern commercial car washing facilities that are outfitted
' with a wash water collection and treatment system, and opt for environmentally friendly
soaps if possible.
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1 �
1
Residents can also install on-site retrofits to improve the stormwater management on an
individual house lot. These can include installation of rain barrels to collect water from '
rooftops through roof leaders. Rainbarrels that are properly fitted with tightly closed
solid tops or a mesh screen at the top should alleviate mosquito concerns as these
precautions will prevent mosquito larvae from hatching out and leaving the barrel. A rain '
barrel program could be established through the municipalities or a local non-profit
organization, in conjunction with a rain barrel distributor, to sell rain barrels at a
discounted price to community members. In addition, other on-site retrofits may include '
installation of a dry well to collect and infiltrate roof runoff and overflow from the rain
barrels, if they have been installed. These and a number of other potential best
management practices that could be used to retrofit a site are described in more detail in '
Section 4.4.
3.3.5 Septic System Maintenance '
Septic systems require regular maintenance and inspection, and require that homeowners
are actively aware of the location and operational characteristics of the system. Most
systems require that the septic tank be pumped out approximately every 3-7 years '
(depending upon the input to the system and the size of the settling tank)to remove the
solids that have accumulated over that time period.
There are many septic system maintenance additives marketed to reduce the
accumulation of solids and the frequency of pumping of the septic tank. However, these
additives can frequently be harmful to the system, particularly when used inappropriately, '
by impairing the microbial community responsible for much of a system's treatment
ability, by reducing the effectiveness of the leach field, and by contributing chemical
contaminants to the underlying groundwater. This is particularly important in coastal '
areas characterized by sandy soils where groundwater movement to receiving waters can
be very rapid. A properly designed, installed, and maintained septic system should not
need chemical additives to function properly. It is important for homeowners to be aware '
of what they put into their septic system and what the potential effects may be. Without
proper maintenance,the system can lose significant treatment capacity and can clog up.
This can cause a failure where the system's leach field fails to leach and the leachate '
breaks out at the ground surface. Alternatively, it could back up into the household.
Both of these scenarios cause a public health concern as well as a threat to local water
resources. '
A public mailing from the municipality can promote septic system maintenance by
reminding residents of maintenance needs. The New York Onsite Wastewater Training '
Delhi provides trainin s throughout the
Network at the State University of New York at De p g g
state and is a wealth of information about septic systems, including proper siting, design
and maintenance. While that program's training is geared primarily at engineers and '
practitioners, the New York State Department of Health website provides information
and a printable pamphlet aimed at residents that describes proper septic system operation '
and maintenance. This pamphlet could be updated to include references to local water
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' resources and connect the need for septic system maintenance to the local resources that
may be threatened or experiencing poor water quality. The Rhode Island Cooperative
' Extension has developed a number of helpful fact sheets aimed at homeowners with
information about septic system maintenance, ways to prolong the life of the system,
ways to upgrade the system to provide better treatment, the effects of additives, and other
' useful information.
The Suffolk County Department of Health Services has also produced a brochure
' entitled, "Home Sewage Disposal Systems in Suffolk County,"which describes a septic
tank and cesspool system that is typical of Suffolk County. This brochure, last updated in
2004, could be improved upon at the county or local level to provide additional
' information about how to upgrade or improve on-site wastewater treatment through
innovative wastewater design. This would be useful for homeowners, especially those
with aging systems (25-30 years old) and in need of significant repair or replacement.
' 3.4 Public Education and Outreach—Recommended Programs
' The following provides a menu of activities that could be undertaken as part of a
watershed-wide or town-wide outreach and education program to address the
environmental health of the coastal water resources of the Peconic Estuary. These
' activities are designed so that they could focus on one or a combination of the five areas
discussed above. These activities could be implemented by each municipality, in
' conjunction with the Peconic Estuary Program, Suffolk County, homeowners'
associations, local schools, or other active citizens groups.
3.4.1 Watershed Awareness Day
Hold a watershed awareness day, perhaps associated with an Earth Day program. The
towns and/or villages in the watershed could organize a watershed awareness day to take
place along the shore or at an open space within the watershed. This could include
educational booths, games related to water quality, demonstrations of innovative
technologies, sales of rain barrels and native grass seed, a swim or kayak race, a road race
' through the watershed, and/or an afternoon or evening clambake. This is a great way to
get people outside, making the visual and experiential connection between the coast they
love and the watershed in which they live and play.
' 3.4.2 Media Campaigns
A host of media campaigns could be developed with specific messages regarding
applicable management strategies such as residential septic system maintenance, repair or
replacement; residential fertilizer management; shoreline vegetation management; car
washing; or pet waste management. These campaigns can include fliers and brochures to
' be distributed at community events or mailed out with utility bills, as well as posters to be
distributed and posted in municipal offices,public libraries, schools, and other highly
visible areas. Articles, or a series of articles, can be developed for the local newspaper to
' focus people on watershed management. Television advertisements or stories on local
television stations or the local cable access stations can be devoted to homeowner
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activities that impact the watershed. Brochures related to pet waste clean up could be ,
handed out with dog licenses and distributed by local veterinarians. These efforts could
be tied to the public outreach and education requirements of the State Pollutant Discharge '
Elimination System(SPDES) permits that may be required for some municipalities
regulated as separate storm sewer system communities.
3.4.3 Institution of an "Adopt-a-Watershed" Organization '
Such an organization would be tasked with cleaning up litter, monitoring storm drain
outfalls, or promoting watershed stewardship. This type of organization can make a big '
difference just by being aware of the activities within the watershed and along the pond
shores. Monitoring of storm drain outfalls can be done with the use of simple water
quality kits in conjunction with observations. This activity serves as education,but also '
as a means to gauge any significant changes that may be occurring in the watershed. This
is also a great way to get children involved.
3.4.4 Demonstration Projects ,
Projects that can be used to illustrate a vegetated buffer, alternative stormwater
management techniques, or a low-maintenance lawn can be invaluable in an education '
campaign. These are typically done on publicly-owned land or on a private individual
lot, if there is an enthusiastic and willing home owner. Demonstration projects are
helpful because they allow people to see a work in progress and a finished product, so ,
they can know what to expect and they can evaluate the outcome realistically. They can
also involve members of the general public in the planning and implementation of the
demonstration project, which serves as a great educational experience. Once a project '
has been undertaken, the development and implementation phases can be documented in
photographs which can be used in mailers, brochures, posters, and a media campaign.
They can serve as a centerpiece for a local news story as well. Signage about the project '
can be placed at the edge of the site to catch the attention of passersby and provide
educational information and a place to go for more information to anyone who is
interested. '
One example of a successful demonstration project took place at Long Lake in Littleton,
MA. Long Lake was in a deteriorated state due to nutrient loading from nonpoint source '
pollution. The town used a grant to work with a consultant to retrofit a portion of the
Long Lake watershed by installing rain gardens, grassed swales, rain barrels and a
constructed wetland park with walkways for the public to enjoy the area and learn about '
the stormwater management practices. A description of the project, with project design
information and photographs, is posted on the state Executive Office of Environmental '
Affairs website and serves to inform other interested people about the project.
3.4.5 Watershed Clean-up Days ,
A community or community organization can coordinate a watershed clean-up day to
bring volunteers together to pick up litter and solid waste debris throughout the
watershed. These events can be fun, and allow people to see water bodies and areas of '
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' the watershed that they may not be familiar with. They help to give people a sense of
ownership and stewardship for the watershed beyond the single clean-up event.
' 3.4.6 School Watershed Science Programs
Science and humanities programs in local schools can help to educate young people on
' the various themes of watershed management, and the connection between human land
uses and the water quality in the Peconic Estuary. Hands-on school programs related to
the environment may include water quality monitoring, gardening, recycling, and
composting. These programs can serve as a terrific vehicle to teach students about
watershed management and stewardship.
' 3.5 Summary of Programmatic Recommendations
While this section introduced several programmatic opportunities, regular inspections and
' maintenance of the stormwater infrastructure should be the top priority. Without a long-
term inspection/maintenance program in place, any new or existing stormwater BMPs
implemented in the watershed will eventually lose effectiveness over time. Even the best
BMPs are only as effective as their maintenance plan. Next,the review process for new
and redevelopment could be amended to require developers to utilize specific BMPs and
alternative site design techniques right from the beginning of a development project,
' reducing potential water quality impacts. Finally, the various public education focus
areas and programs presented above can be very effective in improving the health of the
' watershed. No one outreach campaign will be effective for all neighborhoods— they
should be tailored to target the specific issues in various areas throughout the watershed
based on demographics, density, age of the neighborhood, current lawn care methods,
etc. Older, more established neighborhoods with mature trees and smaller yards tend to
have a lower impact on water quality than new subdivisions with large, cleared lots and
highly manicured yards, and different outreach programs would be needed for each.
' Programmatic costs can pose a problem for some communities. One way to reduce these
costs and improve program effectiveness is to pool resources with other municipalities
' and agencies. Such coordination could be useful for purchasing shared maintenance
equipment such as street sweepers and implementing area-wide educational campaigns.
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4.0 STORMWATER MANAGEMENT WATERSHED ASSESSMENT 1
This stormwater management assessment addresses stormwater runoff as a source of ,
pollutant loading in the Hashamomuck Pond watershed and helps to identify problem
areas and potential areas for the installation of stormwater best management practices
(BMPs) to reduce the load of stormwater pollutants to the pond. The results of this '
assessment are then used to recommend site specific stormwater management
implementation projects in key locations throughout the watershed. By identifying and
prioritizing the most cost-effective retrofit and public outreach opportunities, the town '
has a reasonable set of specific management options to help achieve many of the goals
stated in the CCMP. Successful implementation of the identified opportunities is
expected to help reduce stormwater runoff pollution, improve overall water quality '
conditions, and maintain or improve critical habitat areas.
The existing stormwater management program in the Hashamomuck Pond watershed ,
mainly consists of deep sump and leaching catch basins, roadside drainage ditches and
swales, and detention and infiltration basins. Based on this watershed assessment,
proposed stormwater BMPs were selected to retrofit the existing drainage system to
better manage and treat stormwater before it reaches Hashamomuck Pond.
Potential pollutants and restoration sites for upland areas were also investigated at the t
same time using the Unified Subwatershed and Site Reconnaissance (USSR) procedure,
described in Section 4.7. These upland areas can have significant impacts to the water '
quality of the receiving bodies. The USSR assessments can identify non-point pollutants
of concern for different areas, which can help direct public education efforts and
community action, as described in Section 3.
4.1 Assessment Methodology
Results from the "Peconic Estuary Stormwater Assessment and Planning Tool" (HW, ,
2003) were used in the stormwater management assessment to help direct investigation to
the areas where pollutant loading was the greatest. The discreet drainage areas with all '
the identified drainage structures and outlets within the watershed were overlaid onto the
orthophotographs of the area. This provided an opportunity to pre-select sites for
investigation based on outlet locations and areas that are open(space for BMPs), publicly '
owned, and/or untouched(natural wooded land). The watershed and subwatersheds are
shown and labeled in Figure 4.1.
A rapid and focused field reconnaissance effort in the Hashamomuck Pond watershed '
was conducted. Reconnaissance inventory forms were filled out at each site location.
These forms were later used to rank sites, highlight potential hotspot locations, assess '
varying types of neighborhoods and large pervious areas, and inventory various streets
and storm drains. For example, if there were evidence of too much lawn maintenance in
an area,the recommended actions would include a targeted public education campaign or
collaboration with local landscaping companies. If there were many hotspots in a
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Hashamomuck Pond Subwatersheds Drainage Area & Subwatershed Map
Hashamomuck Pond Watershed
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' watershed, site specific investigations and potential clean-ups would be recommended.
All of the investigated sites were numbered accordingly and discussed in this report. See
' Figure 4-2 for the site locations. A Watershed Assessment Guide has been included in
Appendix B, which includes more details on how to conduct a watershed assessment.
' 4.2 Storm Drainage Assessment and Mapping
Preliminary drainage areas were first delineated through the use of topographic maps.
' Topographic maps allow for a reasonable watershed delineation under natural conditions.
However, construction of impervious surfaces, the use of stormdrain systems, and
grading of land surfaces to accommodate different site designs can significantly alter the
overall size and shape of the watershed. Due to these factors, a field survey is required
for accurate drainage delineation. In an effort for a more accurate drainage delineation,
the Peconic Baykeeper was subcontracted to perform field survey delineations for the
' four priority embayments within the Peconic region(West Neck Bay, Hashamomuck
Pond, Reeves Bay, and Meetinghouse Creek). These delineations included discreet
watersheds that were determined through a combination of natural topography and
' observed structural drainage. The field surveys conducted by the Peconic Baykeeper
were then digitized into GIS and overlaid onto basemaps provided by the Peconic Estuary
Program(PEP). The storm drainage investigation and mapping exercise were conducted
' in 2000, and the results of that program were used in this stormwater management
assessment.
' 4.3 Potential Sites and Best Management Practices Selection
Prior to the field visits for the stormwater management assessment, HW reviewed the
' existing stormwater assessment data(HW, 2003) and identified potential locations for the
installation of stormwater BMPs based on land use, parcel ownership (publicly-owned
land was targeted as a priority), outfall locations,potential conflicts with existing utilities,
effective stormwater capture area, and pollutant source locations.
A stormwater field reconnaissance team then investigated all potential BMP locations. In
' addition to the stormwater field team, a habitat protection field team was deployed at the
same time to identify potential habitat protection locations in the watershed(discussed in
more detail in Section 5.0 of this report). All field work was conducted the week of
September 12, 2005.
' Six sites were selected from the potential locations for further stormwater investigations
based on field assessments of site conditions, physical constraints, and retrofit feasibility
(see Table 4-1). Sites were selected in subwatersheds 5, 7, 9, 14, 18, and 22, and the
' results of the in-depth investigations are described in Section 4.6. For each site, detailed
field notes, inventory forms, and photos were collected and can be found in Appendix D.
II
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_ Hashamomuck Pond Watershed Proposed i
OutfallsHashamomuck Pond Subwatersheds M Proposed BMP Drainage Areas N
Inventory
•' • / Field Locations
InfiltrationEl Outlet Catchbasin --] Neighborhood Source Assessment Hashamornuck Pond Watershed
FNSA Pervious Area Assessment Town of
Catch Basin ® Southold
PEP • 1 • 1.
ECM PEP Drywells 875 Field lnventory_Hash.mxd
' Table 4-1. Summary of Proposed Best Management Practices for the Hashamomuck Pond Stormwater Drainage Area, Long Island, New York
' D.A. BMP Estimated Pollutant Removal Efficiency Estimated Costs (for PlanningPurposes only)
BMP Captured
Location' BMP Concept Design BMP
Site # Total Imp. Metals
Area Area Criteria2 Fecal < Hydro- Design,Permitting, Annual Routine
Coli. Total N Total P TSS (Cd,Cu, carbons Capital Cost Contingencys Total Maintenances
(ac) (ac) Pb,Zn)
' Grass channel to pre-treat and convey
surface drainage from the roadway to a Grass Channel,
bioretention system for half of the roadway. Treatment for the Bioretention
End of Laurel Avenue A d swale for treatment for the other half 0.71 0.45 90%of average System,D ND-98 ND-70 9-75 41-99 10-99 ND-62 0 0
H-5 dry Y Dry $68,000 $21,000 $89,000 3/0-7/0
'
of roadway. Ruaoannual stormwaterff from the bioretention Swale,Oil/Grit
and dry Swale will collect into an oil/water runoff volume. Separator
separator.
t Grass channel on both sides of the roadway Treatment for the Grass Channel,
H-7 Long Creek Drive to pre-treat and convey surface drainage into 6.09 1.4 90%of averageBioretention 0-98 ND-70 9-75 80-99 42-99 62 $102,000 $31,000 $133,000 5%-7%
a bioretention system(on-line). annual stormwater System
runoff volume.
Grass channel to pre-treat and convey
surface drainage into a proposed sediment Grass Channel,
' forebay prior to the existing detention pond. Treatment for the Sediment
Upgrade existing outlet to a low-flow orfrce 90%of average Forebay,Pond
H-J Bayview Ave stureture and provide some pond restoration 0.23 0.16 annual stormwater Restoration, 0-65 ND-33 9-55 80-81 24-73 62-83 $87,000 $27,000 $114,000 3%-7%
(incl.removal of tree overhang,introduce runoff volume. Low-flow
' more wetland plants,etc.). Proposed pond Orifice Outlet
restoration treats much larger watershed.
Grass channel on both sides of roadway to Treatment for the90%° of average Grass Channel,
H-14 Dons Way pre-treat and convey surface drainage into a 0.13 0.13 annual stormwater Broretention 0-98 ND-70 9-75 80-99 42-99 62 $38,000 $11,000 $49,000 5%-7%
bioretention system. runoff volume. System
' Dry Swale on both sides of roadway to pre-
treat and convey surface drainage from the Treatment for the Dry Swale,
Comer of Colony Road& roadway. The runof7will overflow into 290%of average
H-18 Bayview Avenue catchbasins and collect in an oil/water '27 0.59 annualstormwater Oil/Grit 0-ND ND-15 9-37 41-81 10-71 ND-62 $87,000 $26,000 $113,000 3%-7%
' seperator prior to discharge into the existing mnoff volume. Separator
infiltration pit.
Micro-Bio inlet with a stone curtain to Treatment for the
' pretreat stormwater prior to discharge into an ° of average Micro-Bio
Intersection of Grove Road&
H-22A Mill Creek Drive existing vegetated channel. tl sediment 4.48 0.9 90/°annual stormwater Inlet,Sediment 65-98 33-70 51-75 80-99 24-99 62-83 $77,000 $24,000 $101,000 3%-7%
forebay is proposed at the outlet prior to Forebay
discharge into the existing vegetated channel runoff volume.
Dry swale on both sides of roadway to pre-
treat and convey surface drainage from the Treatment for the Dry Swale,
' H-226 Grove Road roadway. The mnoff will overflow into 1.34 0.34 90%of averageOil/Grit 70-ND ND-15 9-37 41-81 10-71 ND-62 $57,000 $17,000 $74,000 3%-7%
catchbasins and an oil/water stormwaterwater separator and runoff volume. Separator
discharge into Hashamomuck Pond.
' D.A. = Drainage Area
1 Note.'Site#'s refer to preselected sites. Based upon actual field visits,some sites were removed from further consideration.
1 Note:Because this project is a retrofit of an existing stormwater system and is not being developed as the direct result of a new construction project,the proposed BMPs are not subject to the full suite ofstormwater management standards in the New York Stormwater Management Design Manual.
' 3 Source: Center for Watershed Protection. 1998. Cost and Benefits of Storm Water BMPs,Final Report 9/14/98. Prepared for:Parsons Engineering Science under EPA Contract 68-C6-0001. WA 2-15. Task 6.
4 Source:Schueler, T 1997. Comparative Removal Capability of Urban BMPs: A Reanalysis. Watershed Protection Techniques,2(4):515-520.
5 Note: This cast is estimated to be 30%of the Capital Cost. Source:Center for Watershed Protection. 1998. Cost and Benefits of Storm Water BMPs,Final Report 9/14/98. Prepared for:Parsons Engineering Science under EPA Contract 68-C6-0001. WA 2-15. Task 6.
6 Note: This cost is estimated to be a percentage of the Capital Cost. Source:Center for Watershed Protection. 1998. Cost and Benefits of Storm Water BMPs,Final Report 9/14/98. Prepared jar:Parsons Engineering Science under EPA Contract 68-C6-0001. WA 2-15. Task 6.
' 7 Source:Schueler, T. 1997. Performance of Oil/Grit Separators in Removing Pollutants at Small Sites. Watershed Protection Techniques,2(4):539-542.
NA =not applicable. ND=not able to be determinedfrom the available data.
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' 4.4 Description of Proposed Best Management Practices
' The potential BMPs considered for each of the candidate locations were selected and
designed with the goal of improving the overall water quality of the stormwater
discharging to the subject watersheds of the Peconic Estuary. The primary pollutants of
' concern for this area are nitrogen and bacteria. However, the effectiveness for structural
BMPs to remove bacteria is limited; controlling the source of bacteria through public
education is arguably the most effective method for bacteria reduction. Thus, the most
' appropriate and effective BMPs were selected for each retrofit location with an emphasis
on nitrogen removal. If a particular BMP that has high nitrogen removal capability was
not feasible due to site constraints, alternative BMPs were considered to provide removal
' for other types of stormwater pollutants such as total suspended solids (TSS), metals or
hydrocarbons.
' Based on the New York State Stonnwater Management Design Manual (NYSSMDM),
potential BMPs were sized to capture and treat 90% of the average annual stormwater
runoff volume (Water Quality Volume, WQv). As a result, potential BMPs were sized to
capture and treat the 1.2-inch storm event runoff from the contributing impervious areas
to the maximum extent practicable. However, because this watershed management plan
is proposing retrofits to the existing stormwater system, site constraints sometimes
' limited the available area for BMP construction, and the proposed BMPs at certain
locations were, therefore, sized smaller than the WQv. Catch basin inserts were not
considered due to their low removal rates for nitrogen and bacteria and high maintenance
' burdens. See Appendix A for more information on catch basin inserts.
All BMP recommendations occur under the conservative assumption that no other BMP
' is being implemented simultaneously. The pollutant removal efficiency estimated for
each BMP is based on the assumption that each BMP is implemented independently of all
' others. However, it is recommended that a combination of BMPs be implemented jointly
to address as large an area as possible within the study area to achieve a greater
cumulative pollutant reduction at the outfall.
' The BMPs proposed for the Hashamomuck Pond watershed include bioretention systems,
micro-bioretention inlets, constructed wetlands, dry swales, grass channels, oil/grit
separators, and sediment forebays. See Appendix C for a detailed description of each,
including schematics, design guidelines, and maintenance requirements.
4.5 Retrofit Ranking System
Watershed planning recommendations generally come in two categories: (1) regulatory
' and programmatic actions or(2)restoration and protection projects. Regulatory and
programmatic actions include changes to local codes, ordinances and programs that are
derived from an audit of local government capacity to protect the watershed. Examples
' of regulatory actions include adopting a stream buffer ordinance, encouraging or dictating
conservation-oriented design of land development projects, and establishing stringent
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stormwater criteria. Hiring watershed coordinators, erosion and sediment control (ESC) '
inspectors, and executing a municipal street sweeping program are considered
programmatic actions. Priority protection and restoration projects require '
implementation of important on-the-ground projects. Protection objectives generally
involve land acquisition or applying conservation easements. Restoration projects
include stream restoration, stormwater retrofits, and riparian reforestation, etc. '
Since most communities will not be able to implement all the recommended actions or
projects identified, it is important to go through a ranking process to identify priority '
sites. Not all recommendations are equal when it comes to implementation. Some
recommendations, such as regulatory changes or land acquisition, may be more time
sensitive than restoration projects, particularly in areas expecting significant development ,
pressures in the short-term. Many large-scale stormwater retrofit projects require detailed
planning and permitting which takes time, while buffer planting or trash cleanups are
easy projects that can be completed in a few days. '
Ranking candidate projects allows restoration sites to be compared together on a common
basis to find the most cost-effective and feasible projects in the watershed. One of the '
key decisions in project ranking is whether to evaluate similar projects with the same
basic purpose (e.g., stormwater retrofits vs. shoreline erosion control) or evaluate all
different types of projects together; there are pros and cons to each approach. In general, ,
it is probably preferable to assess all groups of projects at the same time, as long as the
ranking factors can be arranged to compare the relative merits of each project. In this
case, however, since the primary focus of this project is to evaluate stormwater '
management implementation, we compared stormwater retrofits in the ranking system.
Each selected site was ranked based on a Retrofit Ranking System. The proposed retrofit '
ranking system includes the following major factors:
1. Pollutant Removal Potential ,
• Impervious area treated
• Percent of water quality target volume treated
• Pollutant load reduction ,
2. Project cost
3. Implementation feasibility based on ownership, wetland
impact/permitting, access, maintenance, and utilities '
4. Supplemental benefits such as habitat and public benefit
The ranking is based on a 100-point scoring system. The basic concept is to evaluate the '
relative merit of proposed retrofit sites by assigning points to a site based on its ability to
meet various criteria under each of the four major factors cited above. Summing the '
assigned points for each of the factors gives an overall site score. Sites with the highest
score represent the best overall candidates for implementation from a stormwater
management vantage point. '
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' The ranking system places an emphasis on (by weighting more heavily) the pollutant
reduction potential. Specifically, 45% of the total points have been allocated to this
' category (impervious area treated, water quality volumes treated, and pollutant
reduction). Another 45% of the points have been allocated to project cost and
implementation. The cost estimates are based on a combination of compiled data in
' "Costs and Benefits of Stormwater BMPs" (Center for Watershed Protection, 1998) and
best professional judgment based on experience. The exact costs will vary from these
estimates based on final engineering design, permitting and contingencies. Design,
' permitting and contingency costs can be generally estimated at approximately 30-35% of
the base construction costs (CWP, 1998). The remaining 10% of the points is divided
between supplemental environmental and public benefits.
The rationale for the emphasis on the area and volume of water treated as well as the cost
and feasibility of a project is two-fold. First, one goal of the retrofit approach is to
' manage a large percentage of the untreated impervious area runoff, in order to maximize
water quality benefits to receiving waters. Therefore, those retrofit sites that are able to
capture and effectively treat a larger area of impervious surface are deemed to be more
important and valuable and thus assigned higher point values. Second, the feasibility of a
proposed retrofit, in terms of both cost and implementation is important. Simply put,
there are frequently "fatal flaws" for proposed retrofits in the form of capital costs,utility
' conflicts, private ownership, and access (to name a few). There is little point in
proceeding with a retrofit design concept if there is a high probability that an existing
constraint cannot be overcome. Therefore,proposed retrofits where these types of
' constraints are minimal or non-existent will be awarded higher point values. Specifics of
the ranking are included in Table 4-2 and results are summarized in Section 4.6 below.
4.6 Investigated Sites and Selected BMP Descriptions
The following are descriptions of the seven selected BMP sites identified in the
Hashamomuck Pond watershed. Figure 4-2 illustrates the locations of the potential BMP
sites. Inventory forms, detailed sketches, maps, site photos, conceptual design plans, and
' calculations for each site are provided in Appendix D. BMPs were chosen to match site
characteristics with recommended design criteria. The main characteristics that
determine the type of BMP chosen include depth to groundwater, watershed area,
' available land space, and drainage system or other infrastructure constraints. The
primary pollutant of concern for this study is nitrogen; however, at a selected site, if a
particular BMP that has high nitrogen removal is not feasible due to site constraints,
' alternative BMPs were considered to provide removal for other types of stormwater
pollutants.
I ' i
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Table 4-2: Hashamomuck Pond Retrofit Ranking Summary
H-9 Site H-7 H-5 H-22A H-18 H-22B H-14
Grove
Stormwater Retrofit Technical Feasibility Long Creek Long Creek Laurel Ave. &Mill Colony Rd.
Dr.(Pond) Dr. &Bayview Grove Rd. Dons Way
Creek Dr. Ave.
1a.Impervious Area Treated 8.49 7.93 2.53 5.07 3.34 1.90 0.74
=/,rte/Ataai`30
1 b.%of Water Quality Volume Treated
7.50 1.56 7.50 2.50 7.50 7.50 7.50
=WQVmQ/WQVdesign-7.5
1c.Pollutant Load Reduction
Based on type of facility and ability to remove total 2.48 4.88 3.00 1.43 1.13 1.13 4.88
nitrogen(eff. '7.5)
1.Pollutant Removal Potential 1s 1413_ 9 12 11 13
Vittall Possible Polnb
2.Project Cost 12 12 ti 11 8 11 1
(Total Possible Points 1
3a.Ownership 15 10 10 10 10 5 5
Private Land=0, Public Land= 15
3b.Wetland Impact/Permiting 3 5 5 0 5 5 3
Yes=0, No=5
3b.Access 2 3 3 3 3 3 3
Poor=0, Good =3
3c.Maintenance 1 2 2 1 1 1 2
High=0, Low=3
3d.Utilities 2 2 4 4 2 2 2
Major=0, No Impacts=4
3.Implementation 23 22 24 1s 21 16 1s
(Total Possible Points 30
4a.Habitat 5 3 3 3 0 0 3
Provides=5, Does Not Provide=0
4d. Public Benefit
Benefits another habitat= 1
Public/Education Program=2 5 3 3 5 4 3 4
Constructed or Maintaned by Volunteers= 1
No Permenent Loss of Recreational Features= 1
4.Supplemental Seno is 10 6 6 8 4 3 7
I(Total Possible Pointe 10
Total Score 84 54 51 48 45 40 36
Maximum Score m 100
Ranking Ranking
i 1
' 4.6.1 Site H-5—End of Laurel Avenue
Site H-5 is located in subwatershed H-5 at the end of Laurel Avenue, abutting Long
' Creek which flows into Hashamomuck Pond. The drainage area is 0.71 acres, of which
63% is estimated to be impervious, mostly from Laurel Avenue. Untreated runoff from
the pavement runs down Laurel Avenue into an existing eroded channel and discharges
' directly into Long Creek. This location is also a popular small boat launching area for
fishermen heading to Hashamomuck Pond. There are signs of sediment build up along
the roadway and at the entrance of the eroded channel.
' The BMP for this site consists of pretreating the runoff with a series of grass channels
and dry swales, and then treating the runoff with a bioretention facility,prior to outletting
into Long Creek. The bioretention facility could be situated on an adjacent privately
owned empty lot with an easement, or situated in the roadway,utilizing approximately 20
feet of the roadway from the existing end of roadway. Due to site constraints,the
' bioretention facility is sized to treat only half of the roadway. The runoff from the other
half of the roadway will be treated in a designed dry swale prior to being discharged into
Long Creek. The conceptual layout and all associated forms and site photos can be found
' in Appendix D-1.
Site H-5 ranked third overall. The major factors that contributed to this rank were the
' pollutant removal potential and implementation factors. Because this site is a popular
boat launching area,this project would provide a great opportunity for public awareness
and education on watershed management.
4.6.2 Site H-7—Long Creek Drive
This site is located in subwatershed H-7, approximately 200 feet west of Laurel Avenue
' on Long Creek Drive. The contributing drainage area is approximately 6 acres, of which
23% of it is impervious. The site of the BMP is located at a natural low point in the
roadway and there is an existing catch basin which overflows to an eroded gully and
' ultimately ends up in Long Creek. The existing drainage feature consists of a catch basin
with an 8-inch overflow pipe and two 3-inch overflow pipes, all of which are clogged.
There are obvious signs of sediment buildup in and around the catch basin, and severe
' gully erosion downslope.
The proposed BMP for this site is a bioretention facility with grass channels for
' pretreatment on both sides of the contributing roadway. The bioretention facility is
proposed to be an on-line (primary collection) system due to the site constraint(existing
large trees on the property). An extensive erosion control measure is required on the
' downstream edge of the bioretention to prevent washout of the facility during large storm
events. The conceptual layout and all associated forms and site photos can be found in
' Appendix D-2.
This site was ranked second out of the seven potential sites in the watershed. It ranked
' highest in project cost, and second and third in pollutant removal potential and
implementation, respectively. Since the BMP site is proposed to be located on a private
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wooded lot, an easement would be required. If an easement cannot be obtained, this site ,
would drop to a lower ranking.
4.6.3 Site H-9—Bayview Avenue '
This site is situated in subwatershed H-9 at an existing constructed pond for stormwater
detention and treatment. The pond appears to be fed by both groundwater and by an
intermittent stream during wet weather. The pond outfitted with an outlet structure(stand '
pipe) that detains stormwater below a specified overflow elevation. During dry weather,
stagnant water remains in the pond below the overflow elevation. This pond is the last in
a series of ponds upstream of it,prior to discharging into Long Creek. The pond is '
situated on private property, adjacent to a residential home. However, during the site
visit the property owner expressed interest in rejuvenating the pond and is willing to
cooperate with any plans to upgrade the pond. ,
There is also a small section of roadway from which untreated runoff drains to a catch
basin and discharged directly down stream of the pond. The proposed BMP concept for '
this site is to collect this untreated roadway runoff and pipe it to the proposed sediment
forebay for pretreatment before discharging to the existing detention pond. Another
aspect of the proposed BMP at this site is to provide pond restoration to improve the '
quality and aesthetics features of the pond. This would include: pruning back the trees
over the pond to provide more sunlight, introducing more and a diverse selection of
wetland plant species to the pond, creating a natural berm between the inlet(sediment '
forebay) and the existing outlet(stand pipe) to create a longer flow path for stormwater
treatment(prevent short circuiting), replacing the existing outlet with a new outlet that
incorporates a low flow orifice (to prevent the pond from becoming stagnant during the '
dry season), and installing a trash rack to prevent clogging of the outlet. The entire
subwatershed area is approximately 6.6 acres that is collected and treated in a series of
ponds (natural and constructed). The drainage area that contributes untreated runoff is '
approximately 0.23 acres of which 70% is impervious. The conceptual layout and all
associated forms and site photos can be found in Appendix D-3. '
This site ranked first overall out of the seven selected sites,with the highest individual
ranking for project cost(highest cost per acre of drainage area treated),pollutant removal, '
and supplemental benefits. This site would provide an optimal area for public education
in the neighborhood and with the cooperation of the property owner, implementation is
feasible. '
4.6.4 Site H-14—Dons Way
Site H-14 is a private cottage community overlooking Hashamomuck Pond in '
subwatershed H-14. There doesn't appear to be a formal drainage system on site.
Instead, runoff probably ponds in low lying areas and drains off the roadway to
Hashamomuck Pond. The paved roadway servicing this community is in poor condition ,
and would need to be upgraded for the proposed BMP concept. The contributing
drainage area for treatment is 0.13 acres of which all is from the paved roadway.
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' The proposed BMP concept for this site are grass channels on both sides of the roadway
(newly paved with proper cross slopes) leading to a bioretention system at the end of the
' roadway. The conceptual layout and all associated forms and site photos can be found in
Appendix D-4. This site ranked the lowest of all sites with the lowest raking given to
project cost and implementation. The site is a privately owned community, with little
' incentive for stormwater improvements. The small drainage and treatment area also
detract from its ranking.
' 4.6.5 Site H-18—Intersection of Colony Road & Bayview Avenue
Site H-18 is located in subwatershed H-18. At this site there is an existing infiltration pit
with a 3'x3' grate on the northeast comer of Colony Road and Bayview Avenue.
' Currently, stormwater runoff flows down the roadway from Bayview Ave. and Colony
Rd. and drains to the existing infiltration pit. The drainage area that contributes to this
existing drainage structure is approximately 2.27 acres of which 26 % is impervious.
' The proposed BMP stormwater concept includes a series of dry swales on both sides of
Bayview Avenue, which will drain to an oil/grit separator prior to discharging into the
' existing infiltration pit. The conceptual layout and all associated forms and site photos
can be found in Appendix D-5. This site ranked fifth overall due to the low
supplemental benefits and overall project cost(higher) relative to the other sites.
4.6.6 Site H-22A—Intersection of Grove Road & Mill Creek Drive
This site is located in subwatershed H-22 and has an existing drainage network that
' outlets into an existing vegetated channel,which is tidally influenced. There are two
catch basins in the vicinity, one directly connected to the outfall and the other across the
roadway from the outfall. The drainage area contributing to these two catch basins is
approximately 4.48 acres of which 20% is impervious. In addition to the above drainage
area, the existing outlet maybe connected to a larger system upstream from this
subwatershed. It is unclear what area the contributing drainage network is coming from.
' The proposed BMP for this site has two components. One is a micro-bio inlet at the
corner of Mill Creek Drive and Grove Road to treat the runoff from the roadways prior to
' discharge into the existing vegetated swale. The other BMP is a sediment forebay with
stone check dams in the existing vegetated channel. This will help reduce the amount of
sediment entering Hashamomuck Pond. The conceptual layout and all associated forms
and site photos can be found in Appendix D-6.
t The site was ranked fourth overall, with the lowest pollutant removal potential of all the
sites but high in supplemental benefits. This area is adjacent to a public boat launch,
which provides great public education opportunities for the Hashamomuck Pond
' watershed.
4.6.7 Site H-22B—Grove Road
' Site H-22B is located in subwatershed H-22. This site is situated on Grove Road, east of
Site H-22A. This area reportedly experiences frequent flooding during storm events.
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There are new infiltrating catch basins located at this site which replaced failed ,
infiltrating catch basins. The drainage area contributing to this BMP site is
approximately 1.34 acres of which 25 % is impervious.
The proposed BMP concept for this site includes a series of dry swales along both sides ,
of the roadway to pretreat the stormwater runoff prior to overflowing into a catch basin.
The existing infiltrating catch basin should be removed and replaced with deep sump '
catch basins. The overflow from the catch basins will be directed to an oil/grit separator
prior to being discharged to a new outlet into Hashamomuck Pond. The proposed
overflow mechanism will help alleviate flooding to adjacent properties during large storm '
events. The conceptual layout and all associated forms and site photos can be found in
Appendix D-7.
The largest hurdle at this site is to obtain a drainage easement between homes to install
the new outfall into Hashamomuck Pond. This site ranked sixth overall, due to the likely
implementation problems and low supplemental benefit potential. ,
4.7 Unified Subwatershed and Site Reconnaissance
The Unified Subwatershed and Site Reconnaissance (USSR)procedure was created by '
the Center for Watershed Protection (2004). The USSR is a rapid field survey that helps
identify potential pollution sources and restoration opportunities in the upland areas of a '
watershed. It is a fast and economical approach to characterizing pollutant contributions
over a wide range of urban conditions and identifying stakeholders that can help with the
restoration planning process. By performing the USSR, water managers can gain a ,
greater understanding of the issues facing a watershed. The USSR is comprised of four
major components: Neighborhood Source Assessments,Hotspot Site Investigations, '
Pervious Area Assessments, and Streets and Storm Drains. A separate field form is used
for each assessment component.
The USSR approach was used in the Hashamomuck Pond watershed as a part of the ,
watershed assessment field reconnaissance. The data collected on the upland areas of the
watershed helped identify potential pollution sources that were not apparent from GIS '
data analyses, and in general, helped to characterize the watershed as a whole. This data
framework will help target effective homeowner and commercial education programs, as
well as future restoration projects. In addition, this information forms a baseline to which '
future assessments can be compared in order to determine rate of change in the watershed
(i.e., where pollution problems have increased over time or where education programs
have been successful in modifying certain behaviors). '
In general, the neighborhoods in the watershed have medium to high lawn management
characteristics,meaning that they are mostly likely a significant source of nitrogen. A
targeted public education campaign on low-impact lawn care in the watershed is '
recommended, as well as on-site retrofits such as rain gardens. There were no hotspots
identified, and one pervious area was assessed where reforestation and/or public '
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' education on pet waste is recommended. The leaching pits investigated were in mostly
clogged and in need of maintenance. Recommended actions include a street sweeping
program and catch basin stenciling. More information on the USSR results is found in
the following sections, which summarize each component of the USSR and describe the
specific sites assessed in the Hashamomuck Pond watershed. See the Field Inventory
' Locations Map (Figure 4-2) for the locations of each assessment.
4.7.1 Neighborhood Source Assessment (NSA)
' The NSA is used to evaluate pollutant-generating behaviors in individual neighborhoods
and identify potential restoration opportunities. Field forms are completed on topics
including neighborhood characterization; yard and lawn conditions; driveways,
' sidewalks, and curbs; rooftops; common areas; and initial neighborhood assessment and
recommendations. Three lots are chosen at random to provide an average sample for the
neighborhood. At the end of the assessment, a pollution severity index is assigned, and
' the overall restoration potential is assessed for each neighborhood. Three neighborhoods
were analyzed in the Hashamomuck Pond vicinity (Figure 4-2) and are summarized
below. Please see Appendix E for the completed NSA field forms and site photos.
' NSA H-4
' NSA H-4 is located in watershed H-4 along Long Creek Drive. The neighborhood is
relatively new (approximately 4 years old) and is comprised of greater than 1 acre lots of
single-family homes with garages and full basements. The neighborhood has no
' sidewalks and no common open space. There is a mixture of lots with low percentage of
grass cover(20-25%of lot) and high grass cover(70% of lot). All of the lots exhibit high
turf and landscape management practices. There are few mature trees in this
neighborhood. Several sprinklers were observed running in the middle of a hot day, with
some overlap onto driveways and the road. The neighborhood's stormwater is directed to
the roadway, where it then drains informally into the shoulder areas. There was only one
' leaching catch basin observed in the entire neighborhood.
The pollution severity index for NSA H-4 was high, while the restoration opportunity
' index was moderate. Recommended actions include better lawn/landscaping practices
including rain gardens at the end of downspouts, education on better lawn/landscaping
practice, and water quality swales.
' NSA H-9
' NSA H-9 is directly adjacent to NSA H-4 however the neighborhood is very different in
characteristics. This neighborhood is over 30 years old with mature trees lining the
street. The lot size averages around half an acre, and all of the houses have garages and
' full basements. Approximately 60% of the neighborhood has medium turf and landscape
management practices, with the remainder of the neighborhood equally divided between
' high and low turf and landscape management practices. There are no sidewalks, curbs, or
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gutters present. There is, however, an existing storm drainage system, consisting of '
leaching catch basins that were predominantly clogged and required maintenance.
The initial assessment of this neighborhood shows a high pollution severity index and a '
moderate restoration opportunity index. Recommended actions for this site are, lawn
care education, street sweeping, catch basin cleanout, and water quality swales along the
road for pretreatment. '
NSA H-14
This neighborhood represents a typical seasonal cottage community. Terrace Cottage
Colony is located off of Don's Way and comprised of detached cottages that are situated
on lots less than a quarter acre in size. The estimated age of this area is over 40 years old. ,
There is minimal landscaping, and there appears to be low turf management. 75%of the
neighborhood is under tree canopy. The main driveway into this community is a dirt road
with no sidewalks, curbs, or gutters. '
The pollution severity index and restoration opportunity index for this site is moderate.
4.7.2 Hotspot Site Investigation (HSI) '
Stormwater hotspots are land uses or activities that produce runoff with relatively high
concentrations of pollutants. There are two types of hotspots: those regulated by Federal ,
or State law and those that are unregulated. The following land uses and activities are
considered stormwater hotspots as listed in the New York State Stormwater Management
Design Manual (2003): ,
• Vehicle salvage yards and recycling facilities*
• Vehicle fueling stations '
• Vehicle service and maintenance facilities
• Vehicle and equipment cleaning facilities*
• Fleet storage areas (bus,truck, etc.)* '
• Industrial sites*
• Marinas (service and maintenance)*
• Outdoor liquid container storage '
• Outdoor loading/unloading facilities
• Public works storage areas
• Facilities that generate or store hazardous materials* '
• Commercial container nurseries
• Other land uses and activities as designated by an appropriate review
authority ,
*indicates that the land use/activity is currently regulated
The HSI creates an inventory of storm water hotspots, including regulated and non-
regulated sites, and assesses the severity of each hotspot with regard to its potential to '
generate storm water runoff or illicit discharges. The HSI is also used to propose
appropriate follow-up actions for each hotspot, including recommendation for rapid
enforcement and the feasibility of onsite stormwater retrofits. Field forms are completed ,
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' on topics including site data and basic classification, vehicle operations, outdoor
materials, waste management, physical plant, turf/landscaping areas, stormwater
' infrastructure, and initial hotspot status-index results. Hotspot status for each site is
broken down into four categories: not a hotspot, potential hotspot, confirmed hotspot,
and severe hotspot.
' There were no hotspot sites identified in the Hashamomuck Pond watershed.
' 4.7.3 Pervious Area Assessment (PAA)
The PAA evaluates the existing condition of natural area remnants and open spaces,
identifies their potential management needs, and also helps to determine the reforestation
' opportunities for large pervious areas. Field forms are completed on topics including
parcel description, current vegetative cover, impacts, and initial recommendations.
' One pervious area was assessed in the Hashamomuck Pond watershed(Figure 4.2) and is
summarized below. Please see Appendix E for the completed PAA field forms and site
photos.
PAA H-9
' The pervious area is located on Yennecott Drive. It is a large open park area across from
an existing pond. The park area is surrounding by natural woods and appears to have
been cleared for the purpose of a park. The site is 80%turf cover, 5%herbaceous cover,
5%tree cover, and 10% shrub cover. The area appears to be mowed frequently. The site
receives full sun, and evidence for significant waterfowl use was observed. The pond
appeared heavily eutrophied and drains to an intermittent stream that flows to BMP site
' H-9.
This site could be a good candidate for natural regeneration and may be reforested with
' minimal site preparation. However, the site appears to get significant use for dog
walking, and it is unclear if the community would prefer the existing open park area in
comparison to less-managed open space. At a minimum, education signage concerning
' dog waste and stormwater should be considered at this location.
4.7.4 Streets and Storm Drains (SSD)
The SSD estimates the severity of pollutant buildup on roads and within storm drain
systems and rates the practicability of four municipal maintenance strategies (street
sweeping, storm drain stenciling, catch basin cleanouts, and parking lot retrofits). SSD
' assessments are usually associated with either NSA or HSI sites. Field forms are
completed on topics including location, street conditions, storm drain inlets and catch
' basins, non-residential parking lots, and municipal pollutant reduction strategies. One to
two catch basins are analyzed per NSA/HSI.
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One storm drain was assessed in the Hashamomuck Pond watershed(Figure 4-2) and is ,
summarized below. Please see Appendix E for the completed SSD field form and site
photos.
SSD H-4 '
This neighborhood had only one visible catch basin for the entire area. It is unclear how '
or where the runoff from this site is directed. This storm drain is a leaching catch basin
on the intersection of Long Creek Drive and Park Avenue. It appears to be in relatively
good condition with no debris or sediments at the inlet. This location is an optimal site '
for street sweeping and catch basin clean out if necessary.
SSD H-9 '
A storm drain associated with neighborhood source area NSA-H-9 was assessed. This
storm drain is comprised of a pair of catch basins located on Yennecott Drive and is used '
to drain the roadway runoff as well as convey the existing stream across the street to the
pond.
Most catch basins in this neighborhood are typically leaching catch basins. They all '
appear to need maintenance. There are several highly feasible pollution prevention
strategies for this area, including street sweeping, storm drain stenciling and catch basin '
cleanouts.
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' 5.0 HABITAT PROTECTION OPPORTUNITIES
' HW identified and observed conditions at three separate areas of undeveloped land within
the Hashamomuck Pond watershed and evaluated these areas for existing habitat
' attributes. These three areas,which are within four of the Hashamomuck Pond
subwatersheds, are comprised of a total of seven individual parcels of land. A general
description of each habitat with respect to observed land and water features and current
' status according to the different mapping resources that HW utilized as part of the
assessment is provided below. The information collected enabled us to provide a
suggested ranking of these parcels and provide a rationale for acquisition priority. Figure
' 5-1 shows the location of the potential habitat site investigated, and Table 5-1 provides a
summary of site observations and information collected from conservation mapping.
Each area is identified by parcel ID number(s) from the Suffolk County GIS parcel layer
and grouped by subwatershed.
Parcels 4656 and 4536 (Subwatersheds H4 and H21)
These adjoining parcels are both mapped as Priority Vacant Land and are within the PEP
Critical Natural Resource Area boundary. Both properties support mature,hardwood-
forested habitat, abutting the shoreline of the coastal embayment. Abundant pond
shoreline habitat is present including salt marsh habitat. A pair of eastern box turtles
(Terrepene c. carolina)was found on the northern parcel. This terrestrial reptile species
' likely utilize much of the upland habitat in this area. There are two relatively small
isolated wetlands located on the southern parcel, which likely provide habitat for seasonal
pool-breeding amphibians. The forested upland areas surrounding these pools provide
' non-breeding habitat for amphibians and reptiles potentially using this pool.
Invasive plants were not observed in any significant abundance. There is one residence
' on an adjacent parcel within subwatershed H3 and identified as Low Density Residential.
Some pruning of vegetation has occurred within the understory on the northern parcel to
afford the abutting resident a better view of the embayment.
These two contiguous parcels are ranked higher than most other assessed parcels because
they are adjacent to open water, mature hardwood forest, salt marsh, and other habitat
' types are preserved,relatively undisturbed conditions within these habitats are
maintained, there is a lack of invasive plant communities, and there is little nearby
residential development. Potential for residential development on these parcels is
' relatively high due primarily to their desirable locations.
' Parcels 4536 and 4656 are subsets of a 5.0 acre and a 5.5 acre parcel, respectively. Both
parcels are highlighted as protection priorities in the PEP Critical Lands Protection Plan.
Parcel 4536 met two PEP CLPP environmental criteria as well as at least one priority
' criterion and was determined to be vacant. Parcel 4656 met three environmental criteria
as well as at least one priority criterion and was determined to be vacant.
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Parcel 15584, 15594,
' 5642
.
FParcel 4656, 4536 Overall Rank:4th (o4
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HabitatHabitat Assessment Areas
Subwatersheds with ID Number
Parceis— Hashamomuck P• •
Transportation_ \ Subwatersheds
Surface Water M - - 0.
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Streams 111 09 :. . Figure
' TABLE 5-I PARCEL SUMMARY TABLE—HASHAMOMUCK POND WATERSHED
1
' Land Use,Location, and Conservation Information for Parcel(s)
(Mapping Source: The Nature Conservancy-Long Island)
^C m 00 V ♦+ t O O O
sa
P4 O 4 w d a a+ e 5 O a Pr h :: Comments
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G � S each assessed area is attached)a 7 p
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' 4656 H4/ TFo,SM, The presence of Eastern box turtles was
4536 H21 large 70 • • • • • • SL,CBank, 10 90 high 1 documented. Potential vernal pools are
tPVPs present.
15584 SM,PEM, The amount and locations of wetland
' 5642 H19 large 40 Agri, Stm PSS,TFo, 50 50 low 2 habitats limit development potential in
• • • • • • • •
15594 Phrag-PEM near-water portions of parcels.
' 5178 very TSS,PSS, Both parcels are traversed by a utility
5140 H9 large 90 • • • • TFoPOMdw, 20 80 • high 3 corridor.
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' Key to abbreviations: PFo (Palustrine Forested),PSS (Palustrine Scrub-shrub),PEM(Palustrine Emergent Marsh), Phrag-PEM (Phragmites-dominant emergent marsh), TFo(Terrestrial Forested), TSS (Terrestrial Scrub-Shrub),
OMdw(Open Meadow), SM(Salt Marsh), SL(Shoreline),PVP (Potential Vemal Pool), Agri(Areas actively managed for agricultural use), Stm(Stream), CBank(Coastal Embankment)
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Parcels 15584, 5642, and 15594 (Subwatershed H19)
' These contiguous parcels are identified as either Priority Vacant (Parcel 15584), Priority
Developed but Subdividible (Parcel 5642 —The Arshamomoaque Stables), or Developed
and Agricultural (Parcel 15594). Existing residential development exists to the west,
protected land abuts to the southeast, Colony Road is to the north, and Hashamomuck
Pond abuts to the south. The southern half of each parcel is within the subwatershed.
Field observations occurred in the southernmost portions of parcels 15584 and 5642,
' which are the areas undisturbed by agricultural-related activities. These areas support
wetland habitat and contain primarily salt and brackish marsh that abuts forested and
shrub-dominant upland habitat. Phragmites-dominant marsh is present in certain wetland
' areas.
These parcels rank higher than most other assessed parcels because they are adjacent to
' open water and to protected land,there are a number of quality habitat types, and there
are relatively undisturbed conditions within these habitats. Because the upland areas
within the watershed,particularly near the water, will have limited development
' potential, due to their proximity to existing wetland habitat areas. The acquisition
priority should be lower than other parcels within the watershed that have a higher
development potential.
' Parcels 15584 and 5642 are both subsets of a 14.4-acre and a 13.8-acre parcel,
respectively. Both parcels are highlighted as protection priorities in the PEP Critical
' Lands Protection Plan. Parcel 15584 met three PEP CLPP environmental criteria as well
as at least one priority criterion and was determined to be vacant. Parcel 5642 met three
environmental criteria as well as at least one priority criterion and was determined to be
developed but further subdividable. Priority criteria were used in the PEP Critical Lands
Protection Plan to highlight specific parcels for some form of protection.
' Parcels 5178 and 5140 (Subwatershed H9)
Most of these contiguous parcels are within subwatershed H9, but do not abut
Hashamomuck Pond, are mapped as vacant lands and Community Preservation Fund
Parcels, and are within the PEP Critical Natural Resource Area boundary. The northern
' portions of both parcels are just within the 1,000' Shoreline Buffer Boundary. They
directly abut public roads and contain a significantly large area of densely vegetated and
contiguous shrub-dominant upland habitat and they have a relatively high potential for
' subdivision and future residential development. The western parcel contains a relatively
large buttonbush (Cephalanthus occidentalis) and swamp loosestrife (Decodon
verticillatus) shrub swamp in its southwestern comer. Invasive plants including olive
' (Elaeagnus sp.), multiflora rose (Rosa multiflora), and Oriental bittersweet(Celastrus
orbiculatus) were observed in abundance in the shrub-dominant uplands.
t The in-watershed portions of these two contiguous parcels rank higher than other parcels
because of their relatively large size and the presence of numerous habitat/cover types,
Peconic Estuary-Hashamomuck Pond Report Horsley Witten Group,Inc.
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' 6.0 REFERENCES
' Center for Watershed Protection (CWP) 1997. "National Pollutant removal Performance
Database for Stormwater Best Management Practices". Prepared for the Chesapeake
Research Consortium.
Center for Watershed Protection (CWP) 1998. Cost and Benefits of Storm Water BMPs.
Final Report. Prepared for Parson Engineering Science under contract with US. EPA
' (Contact No. 68-C6-0001, WA 2-15). U.S. EPA, Washington, DC. 60 pp.
Center for Watershed Protection. 2003. NYSDEC Stormwater Design Manual.
' Center for Watershed Protection. 2004. Unified Subwatershed and Site Reconnaissance:
A User's Manual. Urban Subwatershed Restoration Manual No. 11.
' Claytor and Schueler 1996. Design of Stormwater Filtering Systems. for the
Chesapeake Research Consortium. Center for Watershed Protection, Ellicott City,
' Maryland. 179 pp.
Horsley and Witten, Inc., 2003, Peconic estuary Stormwater Assessment and Planning
' Tool.
Peconic Estuary Program, 2001, Comprehensive Conservation and Management Plan.
' Peconic Estuary Program, 2004, Critical Lands Protection Plan.
' Schueler, T. 1997. Comparative Removal Capability of Urban BMPs: A Reanalysis.
Watershed Protection Techniques, 2(4): 515-520.
Southeastern Wisconsin Regional Planning Commission (SWRPC). 1991. Costs of
' Urban Nonpoint Source Water Pollution Control Measures, Waukesha, WI.
U.S. EPA. 1983. Results of the Nationwide Urban Runoff Program, Vol. 1, Final report.
' NTIS PB84-185552.
Vermont Agency of Natural Resources. April 2002. The Vermont Stormwater
' Management Manual. Waterbury,VT.
Peconic Estuary-Hashamomuck Pond Report Horsley Witten Group,Inc.
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APPENDIX A
Catch Basin Insert- Performance Data
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CATCH BASIN INSERT—PERFORMANCE DATA
' Catch basin inserts are attractive retrofit BMPs to some communities due to their relatively easy and low-cost
installation. However, in the end, their cost effectiveness is determined by their water quality benefit and the
maintenance frequency required. Studies have demonstrated that for many applications, frequent maintenance is
' necessary to prevent clogging and stormwater flows bypassing the BMP, as well as the resuspension of
previously captured material. In addition,the water quality treatment provided is variable, and typically, much
lower than many other BMPs. The table below shows removal data from three different studies on a variety of
catch basin inserts available on the market. Total suspended solids (TSS)removal varies from 3-82%,with
generally lower removals of nutrients. Bacteria removals were not tested as a part of these studies.
' Selection of inserts should take into account many factors, such as: predicted flow rates,pollutants of concern,
predicted pollutant concentrations, sediment particle size distribution, maintenance requirements, maintenance
capability, and the current design of the inserts. Catch basin inserts are not practical for large drainage areas or
' for areas with high levels of organic debris. Public education and outreach regarding illegal dumping into storm
drains could decrease maintenance requirements for these BMPs and help avoid clogging and any subsequent
flooding. In addition,regular scheduled inspections and maintenance could result in more effective removals.
' Pollutant Removals (%)
Technology ' TSS Nitro n Total Bacteria
' TKN Nitrate NitriPhte P
StormFilter®with Perlite Filter Media ' 50 24 -13 36 50 ND
Stormwater Mangement, Inc.
Hydro-K1eenTM Filtration System 46-75 0* 0* 0* 0* ND
Hydro Compliance Management, Inc.
Vortechs® System, Model 1000 35 ND ND ND 21 ND
' Vortechnics,Inc.
CrystalStreamTM Water Quality Vault Model 1056' 21 13 25 50** 40 ND
Practical Best Management of Georgia,Inc.
' Arkal Pressurized Stormwater Filtration System 1 82 26 -76 -76 55 ND
Zeta Technology, Inc.
' AbTech Ultra Urban Filter2 45 ND ND ND ND ND
AbTech Industries
AquaShieldTM 2 10 ND ND ND ND ND
' AquaShield, Inc.
DrainPacTM 2 22 ND ND ND ND ND
GeoMarine, Inc.
' HydroCartridgeTM 2 40 ND ND ND ND ND
PacTec, Inc.
' StreamGuardTM' 3 ND ND ND ND ND
Bowhead Manufacturing Co. LLC
FossilFilterTM s
KriStar Enterprises, Inc. 14 ND ND :ND ND ND
ND=No data
* Study indicated that technology was"ineffective"at removal of these constituents
**Study indicated that removal rate may not be accurate due to low influent concentrations
1 ' US EPA-Environmental Technology Verification Program for Stormwater Source-Area Treatment Devices
http7//www.epa.2ov/etv/verifications/vcenter9-9.html Studies completed between 2003-2005.
' 2 Civil Engineering Research Foundation's Verification Report of the Low-cost Stormwater BMP Study
httn'//www mackblackwell org/research/finals/arc20l8/MBTC°/u202018.htm# Toc53367774
s CalTrans BMP Retrofit Pilot Program,Chapter 11 Drain Inlet Inserts,January 2004.
htta//www dot ca gov/ha/env/stormwater/
' A-1
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APPENDIX B
1 Watershed Assessment Guide
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Watershed Assessment Guide:
' A Handbook for Water Managers in the Peconic Estuary Region
1.0 Introduction
1 The Peconic Estuary is located on the east end of Long Island, New York. This ecosystem has
been designated by U.S. Environmental Protection Agency as an "Estuary of National
Significance." Development pressures in an area typically characterized by open space and
agriculture are forcing water managers to plan wisely now in order to preserve and enhance the
water quality and wildlife habitat of the estuary.
In order to plan effectively a watershed assessments should be performed. A watershed
assessment addresses pollutant loading sources and restoration opportunities within subject
watersheds. The assessment has four main elements: data preparation, field reconnaissance,
restoration prioritization, and watershed plan development.
2.0 Data Preparation
Thorough data preparation and review of existing conditions can save time out in the field later
on. Watershed managers should gather as much information as possible about the area of
concern. Geographic Information System(GIS) data are extremely helpful in a watershed
assessment. GIS data layers and water quality data are available for the Peconic Estuary region
through the development of the regional stormwater project. Available data include coastlines
boundaries, topographical contours, critical habitats, existing land use, water quality parameters
' monitored through the Peconic Estuary Program (PEP), shellfish habitat and closings, and field-
identified stormwater discharge locations. In addition to these data, zoning maps, ordinances and
regulations for each town within a study area; aerial photography; analysis of aerial photos by
US Fish and Wildlife Service (USFWS) for eelgrass beds, macroalgae and shoreline hardening
extent; population data; information on swimming beach water quality and closures; number of
boats utilizing the embayment from the Vessels Waste No Discharge Zone application to the US
1 Environmental Protection Agency (USEPA); and other studies related to the water quality,
hydrology, habitat, flushing, etc., specific to the particular embayment may also be collected and
reviewed.
Based on the above data collection effort, drainage basins (watersheds) can be identified for the
receiving body of concern, as well as discreet drainage areas (subwatersheds) within the drainage
basins. Sites for further investigations can be pre-selected based on outlet locations, available
open space (space for retrofits), public ownership, and/or undisturbed lands (i.e., natural wooded
land). Once all sites have been pre-selected, a field reconnaissance can be initiated. A field
reconnaissance serves many purposes such as verifying existing condition information,
'Peconic Estuary Stormwater Assessment and Planning Tool. Horsley Witten Group,October 2003. Prepared for
Peconic Estuary Program.
' B-1
Watershed Assessment Guide July 2006 '
conducting formal investigations for stormwater retrofits, potential pollution sources and '
restoration opportunities in upland areas, and inventorying potential habitat protection areas.
Depending on the breadth of the watershed assessment scope, all or some of these investigations '
can be included in the field reconnaissance.
Prior to any field work, reconnaissance teams should be prepared with the right tools, forms and '
maps necessary for the assessment. A checklist should be prepared. Table 1 includes a sample
checklist used in a previous field reconnaissance.
Table 1. Example of Field Reconnaissance Checklist '
Watershed Stormwater Retrofit and Upland Non-point Source Assessment
Equipment/Data Needs
Watershed Maps (Aerial photography, soils,land use, street maps, USGS quads, '
habitat maps)
1 digital camera per team
❑ 1 calculator per team '
Field forms, clipboard(waterproof, if possible),pencils(waterproof, if possible)
C 1 pry bar per team(to pop Manhole/Catch Basin rims) '
1 screwdriver per team(to help pop Manhole/Catch Basin rims and assess soil
compaction)
❑ 1 flashlight per team '
❑ 1 pair of binoculars per team
1 tape measure per team(25 ft ok, 100 ft, if available) ,
C Safety equipment(first aid kit, sun screen, insect repellent)
❑ Snacks, water bottle
Rain gear(plus umbrella for covering camera/field forms) '
❑ Authorization letter from client(describes nature of project for potential access to
properties) '
Parking display cards (for dashboards of vehicles)
❑ 1 pair of water boots per team(for shallow water access)
❑ Cell phones with team member#s (plus client, other local government contacts) '
❑ Personal items (appropriate clothing, sunglasses, hat, gloves,etc)
3.0 Field Reconnaissance
Field reconnaissance is a must when performing a watershed assessment. The data gathered in '
the office must be field-verified. For example, there may be physical constraints at a site that
appeared promising for restoration on GIS, but the data were either outdated or incomplete. '
Only out in the field can a manager get the full picture of an area. In addition, local residents
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Watershed Assessment Guide July 2006
met in the field may be able to provide additional information about a site that could sway the
ranking of a project.
' 3.1 Stormwater Retrofit Reconnaissance Inventory
The goal of a stormwater outfall and retrofit inventory is to determine potential stormwater best
management practice (BMP) retrofits in a watershed to better manage and treat stormwater
runoff before it enters the receiving waters. Potential locations for the installation of stormwater
BMPs should be pre-selected based on land use, parcel ownership (publicly-owned land
simplifies implementation),potential conflicts with existing utilities, effective stormwater
capture area, and pollutant source locations. Examples of BMPs include the following:
sediment forebays, water quality swales (dry or wet), bioretention systems, constructed wetlands,
infiltration basins, etc. A field crew shall visit and evaluate each site and fill out separate field
forms for each potential BMP retrofit. A sample field form is included in the attachment.
' Data collected in the field and compiled afterwards should include the inventory forms, detailed
sketches of the site, several site photos, conceptual design plans, and calculations for each site.
BMPs should be chosen based on site characteristics that match BMP design criteria. Some
characteristics that determine the type of BMP chosen include depth to groundwater, watershed
area, available land space, and drainage system or other infrastructure constraints. The pollutants
of concern for the study may vary by watershed and could include nitrogen, phosphorus, total
suspended solids (TSS), bacteria, metals or hydrocarbons.
The results of this assessment are then used to recommend site specific stormwater management
implementation projects in key locations throughout the watersheds.
' 3.2 Unified Subwatershed and Site Reconnaissance
' The Unified Subwatershed and Site Reconnaissance (USSR) procedure was prepared by the
Center for Watershed Protection(2004). The USSR is a rapid field survey that helps identify
potential pollution sources and restoration opportunities in the upland areas of a watershed. It is
' a fast and economical approach to characterizing pollutant contributions over a wide range of
urban conditions and identifying stakeholders that can help with the restoration planning process.
By performing the USSR, water managers can gain a greater understanding of the issues facing a
watershed. The data collected on the upland areas of a watershed help to identify potential
pollution sources that are not apparent from GIS data analyses, and in general, to characterize the
watershed as a whole. This data framework will help managers target effective homeowner and
' commercial education programs, as well as future restoration projects. In addition, this
information forms a baseline to which future assessments can be compared in order to determine
rate of change in the watershed(i.e., where pollution problems have increased over time or
where education programs have been successful in modifying certain behaviors).
The USSR is comprised of four major components: Neighborhood Source Assessments, Hotspot
Site Investigations, Pervious Area Assessments, and Streets and Storm Drains. Separate field
forms are used for each assessment component, which are included in the attachment.
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Watershed Assessment Guide July 2006 '
Neighborhood Source Assessment (NSA) ,
The NSA is used to evaluate pollutant-generating behaviors in individual neighborhoods and
identify potential restoration opportunities. Field forms are completed on topics including '
neighborhood characterization; yard and lawn conditions; driveways, sidewalks, and curbs;
rooftops; common areas; and initial neighborhood assessment and recommendations. Three lots
are chosen at random to provide an average sample for the neighborhood. At the end of the '
assessment, a pollution severity index is assigned, and the overall restoration potential is
assessed for each neighborhood.
Hotspot Site Investigation (HSI)
Stormwater hotspots are land uses or activities that produce higher concentrations of pollutants.
There are two types of hotspots, those regulated by federal or state law and those that are '
unregulated. The following land uses and activities are considered stormwater hotspots as listed
in the New York State Stormwater Management Design Manual (2003):
• Vehicle salvage yards and recycling facilities* '
• Vehicle fueling stations
• Vehicle service and maintenance facilities '
• Vehicle and equipment cleaning facilities*
• Fleet storage areas (bus,truck, etc.)*
• Industrial sites* '
• Marinas (service and maintenance)*
• Outdoor liquid container storage
• Outdoor loading/unloading facilities '
• Public works storage areas
• Facilities that generate or store hazardous materials*
• Commercial container nurseries
• Other land uses and activities as designated by an appropriate review authority ,
* indicates that the land use/activity is currently regulated
The HSI creates an inventory of storm water hotspots, including regulated and non-regulated '
sites, and assesses the severity of each hotspot with regard to its potential to generate storm water
runoff or illicit discharges. The HSI is also used to propose appropriate follow-up actions for
each hotspot, including recommendation for rapid enforcement and the feasibility of onsite '
stormwater retrofits. Field forms are completed on topics including site data and basic
classification, vehicle operations, outdoor materials, waste management, physical plant,
turf/landscaping areas, stormwater infrastructure, and initial hotspot status-index results. '
Hotspot status for each site is broken down into four categories: not a hotspot, potential hotspot,
confirmed hotspot, and severe hotspot.
Pervious Area Assessment (PAA)
The PAA evaluates the existing condition of natural area remnants and open spaces, identify
their potential management needs, and also helps to determine the reforestation opportunities for '
large pervious areas. Field forms are completed on topics including parcel description, current
vegetative cover, impacts, and initial recommendations.
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Watershed Assessment Guide July 2006
Streets and Storm Drains (SSD)
The SSD estimates the severity of pollutant buildup on roads and within storm drain systems and
' rates the practicability of four municipal maintenance strategies. SSD assessments are usually
associated with either NSA or HSI sites. Field forms are completed on topics including location,
street conditions, storm drain inlets and catch basins, non-residential parking lots, and municipal
pollutant reduction strategies.
The results of these investigations are used to target specific watershed actions that may include
public education, regulatory code reform, and/or targeted inspections.
3.3 Habitat Reconnaissance Inventory
Areas should be selected for on-site review if they are undeveloped,primarily forested, appear to
contain a significant amount of upland with residential development potential, and are not
' mapped as "Protected Land" according to existing information provided by The Nature
Conservancy (TNC) and/or Suffolk County. These areas can be either stand-alone properties or
areas comprised of a number of abutting properties. Field assessments should generally only
occur within the portions that are mapped within the subwatershed boundary of concern. In
certain instances, you may discover that development is underway on selected parcels; and
therefore, an on-site assessment of habitat features should not be performed. In addition, if an
area is posted with"No Trespassing" signs, the area should not be entered for assessment
without prior premission.
' The field data should constitute the answers to habitat assessment questions and other
observations. Some attributes to consider for assessing watershed habitat include the following:
1) Habitat complexity
• number of plant layers,
' • condition of plant layer coverage,
• spatial pattern of shrubs and/or trees,
• number of cover types in each plant layer,
• ratio of cover types,
• degree of cover type interspersion,
• the presence of undesirable species,
' • percent open water,
• degree of vegetation/water interspersion,
• shape of the wetland/upland edge, and
' . wildlife attractors
2) Features which reduce habitat value
• disturbance of wildlife habitat
• observable contamination
In addition to the above, other habitat attributes to consider include:
' • the proximity of the subject area to residential or commercial development;
B-5
Watershed Assessment Guide July 2006 '
• the proximity of the subject area to protected land; ,
• evidence of land management activities (such as mowing and debris disposal); and
• wildlife species or wildlife habitat use evidence encountered. '
4.0 Prioritizing Restoration Options
Watershed recommendations generally come in two categories: (1) regulatory and programmatic
actions, or(2) as restoration and protection projects. Regulatory and programmatic actions
include changes to local codes, ordinances and programs that are derived from the audit of local '
government capacity to protect the watershed. Examples of regulatory actions include adopting
a stream buffer ordinance, encouraging conservation-oriented design of land development
project, and establishing stringent stormwater criteria. Hiring watershed coordinators, ESC '
inspectors, or building a municipal street sweeping program are considered programmatic
actions. Priority protection and restoration projects require implementation of priority, on-the-
ground projects. Protection objectives generally involve land acquisition or applying '
conservation easements. Restoration projects include stream restoration, stormwater retrofits, and
riparian reforestation, etc.
Since most communities will not be able to implement all the recommended actions or projects '
identified, it is important to go through a ranking process to identify priority sites. Not all
recommendations are equal when it comes to implementation. Some recommendations, such as '
regulatory changes or land acquisition, may be more time sensitive than restoration projects,
particularly in areas expecting significant development pressures in the short-term. Many large-
scale stormwater retrofit or stream restoration projects require detailed planning and permitting '
which takes time, while buffer planting or trash cleanups are easy projects that can be completed
in a few days. ,
Project ranking allows restoration projects to be compared together on a common basis to find
the most cost-effective and feasible projects in the watershed. One of the key decisions in project '
ranking is whether to evaluate projects within the same group (e.g., stormwater retrofits) or
evaluate all different types of projects together. There are pros and cons to each approach. In
general, it is preferable to assess all groups of projects at the same time, as long as the ranking '
factors are compatible among the groups.
A proposed retrofit ranking system could include the following major factors: '
1. Pollutant Removal Potential
• Impervious area treated
• Percent of water quality target volume treated '
• Pollutant load reduction
2. Project cost
3. Implementation feasibility based on ownership, wetland impact/permitting, '
access, maintenance, and utilities
4. Supplemental benefits such as habitat and public benefit
Ranking systems can vary by watershed based on what the specific needs are. The basic concept '
is to evaluate the relative merit of proposed retrofit sites by assigning points to a site based on its
B-6 '
Watershed Assessment Guide July 2006
' ability to meet various criteria under each of the four major factors cited above. A ranking
system can place an emphasis on (by weighting more heavily) a particular factor. For example,
' if the pollutant removal potential is most important, a larger percentage of the total points can be
allocated to that category. Summing the assigned points for each of the factors gives an overall
site score. Sites with the highest score represent the best overall candidates for implementation
from a stormwater management vantage point.
The cost estimates can be based on a combination of compiled data in "Costs and Benefits of
Stormwater BMPs" (Center for Watershed Protection, 1998) and best professional judgment
based on experience. The cost estimate found in the CWP 1998 resource should be modified to
account for elapsed time plus the incurred cost of implementing retrofits versus new
construction. This provides for a more realistic, if not more conservative, cost estimate. The
exact costs will vary from these estimates based on final engineering design, permitting and
contingencies. Design, permitting and contingency costs can be generally estimated at
approximately 30-35% of the base construction costs (CWP, 1998).
5.0 Watershed Plan Development
Once the restoration projects have been ranked, the above information should be compiled into a
watershed plan, complete with all the relevant maps, forms, and other collected data. This plan
can be used to justify specific improvement projects and should be updated if additional
information becomes available or if priorities change. A good watershed plan is an excellent
' reference to have in order to select appropriate improvement projects when funding becomes
available. It also will contain much of the supporting data and rationale necessary to secure
grant funding with specific guidelines. The completion of an effective watershed plan indicates
' that a community or organization has thought through its watershed and strengths, weakness, and
priorities and is prepared to move forward with organized corrective activities.
I
I ,
B-7
Attachment: Field Forms
1. Stormwater Retrofit Reconnaissance Inventory
' 2. Neighborhood Source Assessment
3. Hotspot Site Investigation
4. Pervious Area Assessment
5. Streets and Storm Drains
I
B-9
' Stormwater Retrofit Reconnaissance Inventory
1. Site Number:
' 2. Location (Address and/or Parcel ID)
' 3. Description (preliminary assessment of most likely retrofit-quality, quantity, or both):
4. Unique elements of retrofit (e.g., method of conveyance or stormwater diversion):
5. Date of Preliminary Survey:
6. Property Ownership (public or private):
7. Drainage Area:
S. Approximate imperviousness (%):
9. Adjacent Land Use (Possible conflicts):
' 10. Conflicts with Existing Utilities:
' 11. Construction and Maintenance Access:
' 12. Wetlands Present? ❑ Yes ❑ No
If yes, describe:
13. Retrofit Volume Computations:
14. Photo #
1
' B-11
Stormwater Retrofit Reconnaissance Inventory '
1
15. Additional Notes and/or Sketch Information:
1
16. Site Candidate for Further Investigation: ❑ Yes ❑ No '
B-12 '
Neighborhood Source Assessment NSA
WATERSHED: SUBWATERSHED: UNIQUE SITE ID:
' DATE:_/_/_ ASSESSED BY: CAMERA ID: PIC#:
A. NEIGHBORHOOD CHARACTERIZATION
' Neighborhood/Subdivision Name: Neighborhood Area(acres)
If unknown, address(or streets) surveyed:
❑ Unknown If yes,name and contact information:
Homeowners Association? ❑Y [_1 N
Residential (circle average single family lot size):
❑ Single Family Attached(Duplexes,Row Homes) <'/a '/s '/a Y3 'h acre ❑Multifamily(Apts,Townhomes,Condos)
❑ Single Family Detached <'/< '/C '/2 1 >I acre ❑ Mobile Home Park
Estimated Age of Neighborhood: years I Percent of Homes with Garages: % With Basements_% INDEX*
Sewer Service? ❑Y ❑N 0
' Index of Infill,Redevelopment,and Remodeling No Evidence ❑ <59b of units 5-10%❑>10% 0
xecar d pa ;a3suved far nth ejtke fd!°*ing °'s, P"C"tW Comm uts/Notgs
oa .. andfa�r,site co
B.YARD AND LAWN CONDITIONS
Bl.%of lot with impervious cover
B2. %of lot with grass cover 0
B3. %of lot with landscaping(e.g.,mulched bed areas) O
B4. %of lot with bare soil 0
' *Note: B 1 through B4 must total 100%
B5. %of lot with forest canopy
B6.Evidence of permanent irrigation or"non-target" irrigation 0
High: 0
B7.Proportion of total neighborhood turf lawns with following Med:
' management status:
Low:
B8.Outdoor swimming pools?[-]YON❑ Can't Tell Estimated# 0
' B9.Junk or trash in yards? ❑Y❑N E] Can't Tell 0
C. DRWEWAYS,SIDEWALKS,AND CURBS
' CI. %of driveways that are impervious ❑N/A
C2. Driveway Condition❑Clean ❑ Stained ❑ Dirty ❑Breaking up 0
C3Are sidewalks present? ❑Y ❑ N If yes,are they on one side of street❑ or along both sides❑
--------------- -----
- v .............. - -------------------------- --b
Spotless ❑ Covered with lawn clippings/leaves Recevng non-target' irrigation
0
..
What is the distance between the sidewalk and street. ft.
-- ---—-------------
' Is pet waste present in this area? ❑Y ❑N❑N/A
C4. Is curb and gutter present? ❑Y ❑N If yes,check all that apply: ......................-------- -------------
❑Clean and Dry ❑Flowing or standing water ❑ Long-term car parking ❑ Sediment 0
❑ Organic matter,leaves, lawn clippings ❑Trash,litter,or debris ❑ Overhead tree canopy
* INDEX: O denotes potential pollution source; O denotes a neighborhood restoration opportunity
B-13
Neighborhood Source Assessment
D. Rowrors 1
Dl.Downspouts are directly connected to storm drains or sanitary sewer Q O
D2.Downspouts are directed to impervious surface '
D3.Downspouts discharge to pervious area
D4.Downspouts discharge to a cistern,rain barrel,etc. '
*Note: Cl through C4 should total 100%
D5. Lawn area present downgradient of leader for rain garden? ❑ Y❑N Q '
E.COMMON AREAS
El. Storm drain inlets?- ElY❑ N If yes,are they stenciled? ❑Y ❑N Condition: ❑ Clean ❑ Dirty Q
------- ------------------------------------------------------------------------------------------------------ ------- -------------
Catch basins inspected? ❑Y ❑N If yes,include Unique Site ID from SSD sheet: O '
E2. Storm water pond? Y ❑ N Is it a El wet pond or❑dry pond? Is it overgrown? ❑ Y ❑ N O
What is the estimated pond area. ❑<1 acre ❑ about 1 acre ❑> 1 acre
E3. Open Space? ❑Y ❑ N If yes, is pet waste present? ❑Y ❑N dumping? ❑ Y ❑N O '
-----Buffers/floodplain resent: ❑Y ❑ N If yes,is encroachment evident. ❑ Y ❑N
F.INITIAL NEIGHBORHOOD ASSESSMENT AND RECOMMENDATIONS '
Based on field observations,this neighborhood has significant indicators for the following: (check all that apply) O
❑ Nutrients ❑ Oil and Grease ❑ Trash/Litter E] Bacteria[:] Sediment ❑ Other
Recommended Actions Describe Recommended Actions:
Specific Action
❑ Onsite retrofit potential?
❑ Better lawn/landscaping practice? '
❑ Better management of common space?
❑ Pond retrofit?
❑ Multi-family Parking Lot Retrofit?
❑ Other action(s)
Initial Assessment
NSA Pollution Severity Index '
❑ Severe (More than 10 circles checked)
❑High (5 to 10 circles checked) '
❑Moderate(Fewer than 5 circles checked)
❑None (No circles checked)
Neighborhood Restoration Opportunity Index ,
❑High (More than 5 diamonds checked)
❑Moderate(3-5 diamonds checked)
❑ Low (Fewer than 3 diamonds checked)
NOTES:
B-14 '
Hotspot Site Investigation HSI
Watershed: Subwatershed: I Unique Site ID:
Date: Assessed By: Camera ID: jLikK
' Map Grid: Lat_° '_" Long_ #
A. Site Data and Basic Classification
Name and Address: Category: ❑ Commercial Industrial Miscellaneous
' ❑ Institutional ❑ Municipal ❑ Golf Course
❑ Transport-Related ❑Marina
❑ Animal Facility
SIC code(if available): Basic Description of Operation:
NPDES Status: ❑ RegulatedINDEX
❑ Unregulated F-1Unknown *
' B. Vehicle Operations ❑N/A(Skip to part C) Observed Pollution Source?
Bl. Types of vehicles: ❑Fleet vehicles ❑ School buses ❑ Boats ❑ Other:
B2.Approximate number of vehicles:
' B3.Vehicle activities(circle all that apply): Maintained Repaired Recycled Fueled Washed Painted Stored 0
B4.Are vehicles stored and/or repaired outside? ❑Y ❑N ❑ Can't Tell 0
Are these vehicles lacking runoff diversion methods? ❑Y ❑ N ❑Can't Tell
B5.Is there evidence of spills/leakage from vehicles?❑Y ❑ N ❑Can't Tell 0
B6.Are uncovered outdoor fueling areas present? ❑ Y ❑N ❑ Can't Tell 0
' B7.Are fueling areas directly connected to storm drains? ❑ Y ❑N ❑ Can't Tell 0
BS.Are vehicles washed outdoors? ❑Y ❑N ❑Can't Tell 0
Does the area where vehicles are washed discharge to the storm drain? E] Y El N ❑ Can't Tell
C. Outdoor Materials ❑N/A (Skip to part D) Observed Pollution Source?
Cl.Are loading/unloading operations present?__0 Y ❑ N ❑Can't Tell 0
,yes,are they uncovered and drainin towards a storm drain inlet? ❑ Y ❑N ❑ Can't Tell
' C2.Are materials stored outside? ❑Y ❑N ❑Can't Tell If yes,are they❑ Liquid❑ Solid Description: 0
Where are they stored? ❑ grass/dirt area ❑ concrete/asphalt ❑bermed area
' C3. Is the storage area directly or indirectly connected to storm drain(circle one)? ❑ Y ❑N ❑ Can't Tell 0
C4. Is staining or discoloration around the area visible? ❑ Y ❑N ❑Can't Tell 0
C5.Does outdoor storage area lack a cover? ❑Y ❑N ❑Can't Tell 0
C6.Are liquid materials stored without secondary containment? ❑ Y ❑N ❑Can't Tell 0
C7. Are storage containers missing labels or in poor condition(rusting)? ❑Y ❑N ❑ Can't Tell 0
D. Waste Management ❑N/A (Skip to part E) Observed Pollution Source?
Dl. Type of waste (check all that apply): ❑ Garbage ❑ Construction materials ❑Hazardous materials 0
D2. Dumpster condition(check all that apply): L No cover/Lid is open Damaged/poor condition Leaking or 0
evidence of leakage stains on round ❑Overflowin
D3. Is the dumpster located near a storm drain inlet? ❑Y❑N❑ Can't Tell 0
If yes,are runoff diversion methods berms, curbs lacking? ❑Y ❑N ❑ Can't Tell
E.Physical Plant ❑N/A (Skip to part F) I Observed Pollution Source?
El.Building: Approximate age:_yrs. Condition of surfaces: ElClean ElStained [IDirty ElDamaged 0
_T
' Evidence that maintenance results in discharge to storm drains(staining/discoloration)? ❑Y❑ N ❑ Don't know 0
*Index: O denotes potential pollution source; denotes confirmed polluter(evidence was seen)
' B-15
Hotspot Site Investigation
E2.Parking Lot: Approximate age—yrs. Condition: ❑ Clean ❑ Stained ❑Dirty El Breaking up 0 ,
Surface material ❑Paved/Concrete ❑Gravel ❑Permeable❑ Don't know
E3.Do downspouts discharge to impervious surface? ❑ Y ❑ N ❑Don't know ❑ None visible 0 t
Are downspouts directly connected to storm drains? ❑ Y ❑N ❑ Don't know
E4.Evidence of poor cleaning practices for construction activities(stains leading to storm drain)? ❑ Y ❑N ❑ Can't Tell
F.Turf/Landscaping Areas ❑N/A (skip to part G) Observed Pollution Source? '
P1.%of site with: Forest canopy_% Turf grass_% Landscaping_% Bare Soil- % 0
F2.Rate the turf management status: ❑High ❑Medium ❑ Low 0
F3.Evidence of permanent irrigation or"non-target"irrigation ❑Y ❑N ❑Can't Tell 0
F4.Do landscaped areas drain to the storm drain system? ❑ Y ❑ N ❑ Can't Tell 0
F5.Do landscape plants accumulate organic matter(leaves,grass clippings)on adjacent impervious surface? ❑Y❑N ❑ Can't Tell 0 '
G.Storm Water Infrastructure ❑ N/A (slap to part H) Observed Pollution Source?
GI.Are storm water treatment practices present? ❑ Y ❑N ❑Unknown If yes,please describe: 0
G2.Are private storm drains located at the facility? ❑ Y ❑N ❑ Unknown 0 ,
Is trash present in gutters leading to storm drains?If so,complete the index below.
Index Rating for Accumulation in Gutters
Clean Filth '
Sediment ❑ 1 ❑2 ❑ 3 ❑4 [:15
Organic material ❑ 1 ❑2 ❑ 3 ❑4 [-15
Litter ❑ 1 ❑2 ❑3 ❑4 ❑ 5 '
G3.Catch basin inspection-Record SSD Unique Site ID here: Condition:❑Dirty ❑ Clean
H.Initial Hotspot Status - Index Results '
❑ Not a hotspot(fewer than 5 circles and no boxes checked) ❑ Potential hotspot (5 to 10 circles but no boxes checked)
❑ Confirmed hotspot( 10 to 15 circles and/or 1 box checked) ❑ Severe hotspot >15 circles and/or 2 or more boxes checked
Follow-up Action:
❑Refer for immediate enforcement '
❑ Suggest follow-up on-site inspection
❑ Test for illicit discharge
❑ Include in future education effort '
❑ Check to see if hotspot is an NPDES non-filer
❑Onsite non-residential retrofit
❑Pervious area restoration;complete PAA sheet and record '
Unique Site ID here:
F-1Schedule a review of storm water pollution prevention plan
Notes: '
1
1
B-16 '
' Pervious Area Assessment pAA
WATERSHED: SUBWATERSHED: I UNIQUE SITE ID:
DATE:' _/ / ASSESSED BY: CAMERA ID: PIC#:MAP GRm_ LAT_° 1_"LONG_ LMK#
A.PARCEL DESCRIPTION
' Size:—acre(s) Access to site(check all that apply): ❑ Foot access ❑Vehicle access ❑Heavy equipment access
Ownership:❑Private ❑Public Current Management: ❑ School ❑Park ❑Right-of-way ❑Vacant land
❑Other(please describe)
' Contact Information:
Connected to other pervious area? ❑Y ❑N If yes,what type? ❑Forest ❑Wetland❑Other
Estimated size of connected pervious area: acre(s) Record Unique Site ID of connected fragment:
' ATURAL
FOREST WETLAND
B.CURRENT VEGETATIVE COVER B.CURRENT VEGETATIVE COVER
Bl.Percent of forest with the following canopy coverage: Bl.%of wetland with following vegetative zones:
Open % Partly shaded % Shaded % Aquatic:
*Note-these should total 100% Emergent:
B2.Dominant tree species: Forested:
*Note-these should total 100%
B3.Understory species: B2.Dominant species:
1 B4.Are invasive species present? ❑Y ❑N B3.Are invasive species present? ❑Y ❑N
❑Unknown ❑Unknown
' If yes, %of forest with invasives: If yes, %of wetland with invasives:
Species: Species:
C.FORESTIMPACTS C.WETLAND IMPACTS
C1.Observed Impacts(check all that apply): Lj Animals C1.Observed Impacts(check all that apply): Lj Animals
❑ Clearing/encroachment ❑Trash and dumping ❑ ❑Clearing/encroachment ❑Trash and dumping ❑
Storm water runoff ❑ Other Storm water runoff ❑Hydrologic impacts ❑Other
D.NOTES D.NOTES
1
' E.INITIAL RECOMMENDATION
❑ Good candidate for conservation/protection
' ❑ Potential restoration candidate
❑ Poor restoration or conservation candidate
' B-17
Pervious Area Assessment
1111111POUS AREAS '
A.CURRENT VEGETATIVE COVER
Al.Percent of assessed surface with: '
Turf % Other Herbaceous % None(bare soil)_% Trees % Shrubs %Other_%
(please describe): *Note—these should towl 100%
A2.Turf: Height: inches Apparent Mowing Frequency: Lj Frequent Infrequent No-Mow Unknown '
Condition check all that apply): ❑Thick/Dense ❑Thin/Sparse ❑Clumpy/Bunch ❑ Continuous Cover
A3.Thickness of organic matter at surface: inches
A4.Are invasive species present? ❑Y Lj N ❑Unknown If yes,%of site with invasives: '
Species:
B.IMPACTS
Bl.Observed Impacts(check all that apply): Lj Soil Compaction El Erosion Ll Trash and Dumping '
❑Poor Vegetative Health ❑ Other(describe):
C.REFORESTATION CONSTRAINTS
Cl.Sun exposure: Full sun Partial sun Lj Shade ❑Unknown '
C2.Nearby water source?❑Y ❑N ❑Unknown
C3.Other constraints: ❑ Overhead wires Underground Utilities❑Pavement El Buildings '
❑Other(please describe):
D.NOTES
E.INITIAL RECOMMENDATION ,
❑ Good candidate for natural regeneration
❑May be reforested with minimal site preparation
❑May be reforested with extensive site preparation '
❑Poor reforestation or regeneration site
B-18 '
Streets and Storm Drains SSD
' WATERSHED: SUBWATERSHED: UNIQUE SITE ID:
DATE:_/_/ ASSESSED BY: CAMERA ID:
MAP GRID RAIN IN LAST 24 HOURS ❑Y ❑N PIC#
A.LOCATION
Al. Street names or neighborhood surveyed:
A2.Adjacent land use: ❑ Residential❑ Commercial ❑Industrial ❑ Institutional
❑Municipal ❑ Transport-Related
' A3.Corresponding HSI or NSA field sheet?If so,circle HSI or NSA and record its Unique Site ID here
B.STREET CONDITIONS
' Bl. Road Type: ❑Arterial ❑Collector ❑ Local ❑Alley ❑ Other:
B2.Condition of Pavement: ❑New ❑ Good ❑Cracked ❑ Broken
B3.Is on-street parking permitted ❑Y ❑N If yes,approximate number of cars per block:
B4.Are large cul-de-sacs present? ❑Y ❑N
B5.Is trash present in curb and gutter?If so, Index Rating for Accumulation in Gutters
' use the index to the right to record amount. Clean Filth
Sediment ❑ 1 ❑2 [-13 ❑4 ❑ 5
Organic Material ❑ 1 ❑2 ❑3 ❑4 ❑ 5
Litter ❑ 1 ❑ 2 ❑ 3 ❑4 [-15
C.STORM DRAIN INLETS AND CATCH BASINS
Cl.Type of storm drain conveyance: ❑open ❑enclosed ❑mixed
C2.Percentage of inlets with catch basin Stora e: N/A
Sample 1-2 catch basins per NSA/HSI C3.Catch basin#1 C4.Catch basin#2
Latitude
Longitude ° ° '
' LMK#
Picture#
Current Condition ❑Wet ❑ Dry Wet ❑D
' Condition of Inlet Clear Obstructed Clear Obstructed
Litter Accumulation LJY ❑N ❑Y LJ N
Organics Accumulation ❑Y L N Y N
' Sediment Accumulation Y N YLl N
Sediment Depth in feet ft. ft.
Water Depth ft. ft.
Evidence of oil and grease ❑Y N Y N
' Sulfur smell Y ❑N Y ❑N
Accessible to vacuum truck ❑Y L N LY L N
D.NON-RESIDENTIAL PARKING LOT(>2 acres)
' Dl.Approximate size: acres
D2.Lot Utilization: ❑Full ❑About half full ❑Empty
'
III,Overall condition of Pavement: ❑ Smooth(no cracks) ❑Medium(few cracks) ❑Rough(many cracks)
❑ Very Rough(numerous cracks and depressions)
D4.Is lot served by a storm water treatment ractice? ❑ Y ❑ N If es,describe:
D5.On-site retrofit potent ❑ Excellent ❑Good ❑Poor
' B-19
Streets and Storm Drains SSD
E MUNICIPAL T
UN CIPAL POLLUTANT S RATEGIES '
El.Degree of pollutant accumulation in the system: ❑ High El Medium ❑Low El None
E2.Rate the feasibility of the following pollution prevention strategies:
Street Sweeping: ❑High ❑Moderate ❑ Low
Storm Drain Stenciling: ❑High ❑Moderate ❑ Low
Catch Basin Clean-outs: ❑High ❑Moderate ❑ Low
Parking Lot Retrofit Potential: ❑ High ❑Moderate ❑ Low
CATCH BASIN SKETCHES
#1 #2
1
1
Notes:
1
B-20 '
1
I,
APPENDIX C
1 Description of Proposed Best Management Practices
1
1
1
1
1
1
1
1
1
1
1
' DESCRIPTION OF PROPOSED BEST MANAGEMENT PRACTICES
' The best management practices proposed for implementation at sites in the
Hashamomuck Pond watershed include bioretention systems,micro-bio inlets,
constructed wetland, dry swales, grass channels, oil/grit separators, and sediment
forebays. A detailed description of each is included below.
1. Bioretention System
The bioretenrion system(also referred to as a"rain garden" or a"biofilter") is a
storrnwater management practice to manage and treat stormwater runoff using a
' conditioned soil bed and planting materials to filter runoff stored within a shallow
depression. The method combines physical filtering and adsorption with bio-
geochemical processes to remove pollutants. The system consists of an inflow
' component, a pretreatment element, an overflow structure, a shallow ponding area(less
than 6" deep), a surface organic layer of mulch, a planting soil bed, plant materials, and
an underdrain system to convey treated runoff to a downstream facility (see Figure C-1).
' Figure C-1: Schematic of a Bioretention System (Claytor & Schueler, 1996)
FARM)* L07-1 SHEEMOW4
SRJNE aRJP
CRA55 F/L TER
y y Y Y J y
• " ` r OPT/ONAL
' aalIb' y,k,4� 5wD LAYER
, AREA En?/On/
CPA VELCURIA/N
OR4/N
OVERFLOW
' PLAN `6ERW
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1
' C-1
Bioretention facility surface areas are typically sized at a ratio of 5% of the impervious '
area draining to the facility to capture, manage, and treat runoff from the 1.2-inch
precipitation event (Claytor & Schueler, 1996). Pretreatment for bioretention consists of '
a grass channel or grass filter strip, a gravel diaphragm/stone drop, and a mulch layer.
In addition, there are several physical geometry recommendations that should be
considered in the layout and design of bioretention facilities. Suggested design guidance '
is included in Table C-1.
Bioretention facilities are cost-effective measures designed to help meet many of the '
management objectives of watershed protection. Because these practices are proportional
to the percentage of impervious area, the cost is relatively constant with drainage area.
Unlike retention ponds and constructed stormwater wetlands, whose cost decreases with '
increasing drainage area, bioretention does not benefit from economies of scale. Typical
capital construction costs are in the range of approximately $7 to $8 per cubic foot of
storage. Annual maintenance cost is approximately 5 to 7% of capital construction costs '
or in the range of$900 to $1,000 per impervious acre treated.
Table C-1. Design Guidance for a Bioretention System '
Design Guidance
Minimum width 10 feet '
Minimum length 15 feet
Length to width ratio 2:1
Maximum ponding 6 inches '
depth
Planting soil depth 4 feet
Underdrain system 6" pipe in 8" gravel bed '
Plant spacing trees* at 10-foot centers;
shrubs* at 5-foot centers; t
herbaceous materials* at I-
to 2-foot centers
*See the Native Plant Guide(Table H.5) in the New York State Stormwater Management Design Manual '
for particular native plant species that work well in bioretention systems.
Inspections are an integral part of system maintenance. During the six months '
immediately after construction, bioretention facilities should be inspected at least twice or
more following precipitation events of at least 0.5 inch to ensure that the system is '
functioning properly. Thereafter, inspections should be conducted on an annual basis and
after storm events of greater than or equal to the water quality storm event. Minor soil
erosion gullies should be repaired when they occur. Pruning or replacement of woody '
vegetation should occur when dead or dying vegetation is observed. Separation of
herbaceous vegetation root stock should occur when over-crowding is observed, or
approximately once every 3 years. The mulch layer should also be replenished (to the '
original design depth) every other year as directed by inspection reports. The previous
mulch layer would be removed, and properly disposed of, or roto-tilled into the soil
t
C-2 '
surface. If at least 50% vegetation coverage is not established after two years, a
reinforcement planting should be performed. If the surface of the bioretention system
' becomes clogged to the point that standing water is observed on the surface 48 hours
after precipitation events, the surface should be roto-tilled or cultivated to breakup any
hard-packed sediment, and then revegetated.
' 2. Micro-Bio Inlet
' Micro-bio inlets are small-scale versions of bioretention systems (Figure C-2). They are
recommended at locations where a full-size bioretention system will not fit. Existing
roadside catch basins can be used as the overflow structure, and the filter media and
plantings can be installed around it, forming an island. Curbing with inlet cuts and traffic
bollards are required to prevent damage from vehicles while still allowing stormwater to
' enter. A curtain of stone or gravel should be used to provide pretreatment of the
stormwater prior to the filter portion of this BMP.
Costs for Micro-bio inlets are higher than bioretention systems since additional traffic
control and pavement restoration are needed. Typical capital construction costs are in the
range of approximately $10 to $12 per cubic foot of storage. Annual maintenance cost is
approximately 5 to 7% of capital construction costs.
Maintenance requirements are similar to bioretention systems. Inspections are an integral
part of system maintenance. During the six months immediately after construction,
micro-bio inlets should be inspected at least twice, or more, following precipitation
events of at least 0.5 inch to ensure that the system is functioning properly. Thereafter,
' inspections should be conducted on an annual basis and after storm events of greater than
or equal to the water quality storm event. Minor soil erosion gullies should be repaired
when they occur. Pruning or replacement of woody vegetation should occur when dead
' or dying vegetation is observed. Separation of herbaceous vegetation root stock should
occur when over-crowding is observed, or approximately once every 3 years. The mulch
layer should also be replenished(to the original design depth) every other year as directed
by inspection reports. The previous mulch layer would be removed, and properly
disposed of, or roto-tilled into the soil surface. If at least 50% vegetation coverage is not
established after two years, a reinforcement planting should be performed. If the surface
of the bioretention system becomes clogged to the point that standing water is observed
on the surface 48 hours after precipitation events, the surface should be roto-tilled or
cultivated to breakup any hard-packed sediment, and then revegetated.
1
' C-3
Figure C-2: Schematic of a Micro-Bio Inlet '
Existing Edge of , Existing Grass Area '
Pavement l
Exisfing Catch Basin
6d
r
Concrete Footing
\ � Covered w, Stone
�\
4'PVC Clean Out
_.-.�
Concrete Curb
4"Perforated
PVC Underdrain Flow Flow
Micro-Bio Inlet Schematic Plan '
4'Ponding ,I Existing '
5"±Soil Bed Catch
Existing Street •�I i Basin Existing Grass
I T Mulch , t
i
Concrete Footing., I
Concrete Curb V 3"Gravel Blanket '
2"Above pipe
t'Soil Bed i 2"Below pipe
4" Perforated
PVC Underdrain
Micro-Bio Inlet Schematic Profile
3. Constructed Wetland '
Constructed wetlands are excavated basins with irregular perimeters and undulating ,
bottom contours into which wetland vegetation is purposely placed to enhance pollutant
removal from stormwater runoff. The constructed wetland systems used in stormwater
management practices are designed to maximize the removal of pollutants from '
stormwater runoff via several mechanisms: microbial breakdown of pollutants, plant
uptake, retention, settling, and adsorption.
C-4 '
1
There are four basic designs of free-water surface constructed wetlands: shallow marsh,
' extended detention wetland, pond/wetland system, and pocket wetland. In this study, it is
likely that two of the four may be proposed, a shallow marsh and a pocket wetland,based
on the ability of the chosen sites to meet the specified design criteria for the various types
of constructed wetlands. A shallow marsh stores runoff in a shallow basin (Figure C-3)
and is used to provide channel protection volume as well as overbank and extreme flood
attenuation. Pocket wetlands are similar to shallow marshes; however, they are
' dependant on groundwater to maintain permanent water surface and are only generally
used to provide water quality treatment.
' A site appropriate for a wetland must have an adequate water flow and appropriate
underlying soils. Baseflow from the drainage area or groundwater must be sufficient to
maintain a shallow pool in the wetland and support the vegetation, including species
' susceptible to damage during dry periods. Pretreatment for a shallow marsh or a pocket
wetland consists of a forebay sized to treat at least 10% of the required total water quality
volume. General design criteria for a shallow marsh and pocket wetland are summarized
in Table C-2.
' v V v y °
1t.�✓1 I 1
'SK'a4 Mainunanu
Sadimant I I
_
pool �=`< f ,k Disposal Area ,
b mush
N mush i
Figure C-3: Schematic of a Shallow Marsh / Pocket Wetland (Schueler, 1992)
' C-5
I '
Table C-2: Constructed Wetland Design Criteria Schueler, 1992
Design Criteria Shallow Marsh Pocket Wetland,
Wetland/Watershed Ratio 0.02 0.01
Minimum Drainage Area 25 acre 1-10 acre
Length to Width Ratio
minimum
1:1 1:1
Extended Detention ED No No
Allocation of Treatment Volume 20/40/40 10/40/50
(pool, marsh, ED
Allocation of Surface Area (deep
water, low marsh, high marsh)2 20/40/40 10/40/50
Cleanout Frequency 10yrs 10 yrs
Forebay Required Optional
Micropool Re uired Optional
Buffer 25 to 50 ft 0 to 25 ft
Emphasize wildlife habitat pondscaping plan
Pondscaping Plan Requirements marsh microtopography, optional
buffer
Notes: 1. Ratio of approximate surface area of constructed wetland to the total watershed drainage area
2. Deep water— 1.5 to 6 feet below normal pool level
Low marsh—0.5 to 1.5 feet below normal pool level
High marsh—0.5 feet below normal pool level
Costs incurred for stormwater wetlands include those for permitting, design, construction
and maintenance. Permitting, design and contingency costs are estimated at 25 % of the
construction costs (EPA, 1999). Stormwater wetlands with a sediment forebay can range '
in cost, from $26,000 to $55,000 per acre of wetland(EPA, 1999). This includes costs
for clearing and grubbing, erosion and sediment control, excavating, grading, staking, and
planting. Other sources have reported typical unit base costs for stormwater wetlands
range from $1.20 to $2.50 per cubic foot(CWP, 1998). Maintenance costs for wetlands
are estimated at 2 % per year of the construction costs (CWP, 1998).
Like all stormwater management practices, maintenance is required for proper operation
of constructed wetlands. Constructed wetlands require routine maintenance such as
sediment removal. The majority of sediments should be trapped and removed from the
forebay annually. Careful observation of the system over time is required, for the first
three years after construction, biannual inspections during both the growing and non-
growing season. The vegetative condition should be observed closely to determine the
health of the wetland. Vegetative conditions include the types and distribution of
dominant wetland plants, the presence and distribution of planted wetland species, and
signs that volunteer species are replacing the planted wetland species.
4. Dry Swale
Dry swales are concave, vegetated conveyance systems that can improve water quality
through infiltration and filtering. When designed properly, they can be used to retain and
C-6
1
treat stormwater runoff. Dry swales are appropriate in areas where standing water is not
desirable such as residential, commercial, industrial areas and highway medians. In dry
' swales, a prepared soil bed is designed to filter the runoff for water quality (Figure C-4).
Runoff is then collected in an underdrain system and discharged to the downstream
drainage system. The design objective for dry swales is to drain down within twenty-four
hours of a storm event,which is similar to a bioretention system; except that the pollutant
uptake is likely to be more limited, since only a grass cover crop is available for nutrient
uptake.
Figure C4: Schematic of a Dry Swale (Claytor & Schueler, 1996)
CULVERr
t W6/R GRAVEL "'LET NKK OA"
TRENCH
1 L J Y Y R/R,O1P
{ Y { I W
7
a
x •f•
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M
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TEMP Ft'iYdNG
�k
p .. �.y waOE SdL
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' PROF/L E
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W TJ SANO-;70ti LCiJNJ
\ INF^4:V4-,'ON
TYA'CAL ,SGCT/ON
' DRY SWALE
1
' C-7
The general design of dry swales takes into consideration the following design criteria '
(Table C-3):
Table C-3: Design Criteria for Dry Swales Cla for and Schueler, 1996 '
Desio Criteria
Bottom Width 2 feet minimum, 8 feet maximum, widths up to 16 feet are '
allowable if a dividing berm or structure is used
Side Slopes 2:1 maximum, 3:1 or flatter preferred
Longitudinal Sloe 1.0%to 2.0%without check dams '
Surface storage of water quality volume with a maximum
Flow Depth and Capacity depth of 18 inches for water quality treatment (12 inches
average depth). Adequate capacity for 10-year storm with '
6 inches of freeboard
Flow Velocity 4.0 fps to 5.0 fps for 2-year storm
Length Length necessary to drain Swale runoff for 24 hours '
A designed swale, such as a dry swale with prepared soil and underdrain piping, has an '
estimated cost of$4.25 per cubic foot(SWRPC, 1991). Relative to other filtering system
options, these costs are considered to be moderate to low. Most recent cost estimates
have approximated $19 per linear feet for dry swales. The annual maintenance cost can '
range from 5 to 7% of the construction cost(SWRPC, 1991).
The life of dry swales is directly proportional to the maintenance frequency. The '
maintenance objective for this practice includes keeping up the hydraulic and removal
efficiency of the channel and maintaining a dense, healthy grass cover. The following
activities are recommended on an annual basis or as needed: '
• Mowing and litter and debris removal
• Stabilization of eroded side slopes and bottom '
• Nutrient and pesticide use management
• Dethatchin swale bottom and removal of thatching
g
• Discing or aeration of swale bottom ,
Every five years, scraping of the channel bottom and removal of sediment to restore
original cross section and infiltration rate, and seeding or sodding to restore ground cover '
are recommended.
Dry swales should be inspected on an annual basis and just after storms of greater than or '
equal to the water quality storm event. Both the structural and vegetative components
should be inspected and repaired. When sediment accumulates to a depth of
approximately 3 inches, it should be removed, and the swale should be reconfigured to its '
original dimensions. The grass in the dry swale should be mowed at least 4 times during
the growing season. If the surface of the dry swale becomes clogged to the point that
standing water is observed in the surface 48 hours after precipitation events, the bottom '
should be roto-tilled or cultivated to break up any hard-packed sediment, and then
reseeded. Trash and debris should be removed and properly disposed.
C-8 '
5. Grass Channel
t Grass drainage channels (also commonly referred to as swales) are proposed for
conveyance and pretreatment use (Figure C-5). Grassed drainage channels accent the
natural landscape, break up impervious areas, and are appropriate alternatives to curb and
gutter systems. They are best suited to treat runoff from lower density areas and
roadways. They are often used in combination with other stormwater management
practices as a part of the runoff conveyance system to provide pre-treatment. They are
' designed for water quality treatment and provide limited infiltration to groundwater.
The design criteria for grass channels are similar to dry swales (see Table C-4).
' However, the costs to construct grass channels are much lower because the prepared soil
and underdrain system are not part of the design. Grass channels have an estimated cost
of$0.50 per cubic foot(based on cost per square foot, and assuming 6-inch of storage in
' the filter) (SWRPC, 1991). The annual maintenance cost can range from 5 to 7 % of the
construction cost(SWRPC, 1991).
' Similar to dry swales, the lifetime of grass channels is directly proportional to the
maintenance frequency. The maintenance objective for this practice includes preserving
or retaining the hydraulic and removal efficiency of the channel and maintaining a dense,
healthy grass cover. The following activities are recommended on an annual basis or as
needed:
' . Mowing and litter and debris removal
Stabilization of eroded side slopes and bottom
' . Nutrient and pesticide use management
Dethatching swale bottom and removal of thatching
Discing or aeration of swale bottom
' Table C-4: Design Criteria for Grass Channels Cla for and Schueler, 1996
2 feet minimum, 6 feet maximum, widths up to 12 feet are
Bottom Width allowable if a dividing berm or structure is used
Side Slopes 3:1 or flatter
-Longitudinal Sloe 1.0%minimum, 4.0%maximum
Flow Depth and Capacity 4 inch for water quality treatment
t Flow Velocity 1.0 fps for water quality treatment, 4.0 to 5.0 fps for 2
year storm, 7.0 fps for 10-year storm
Length Length necessary for 10-minute residence time
' C-9
1
Figure C-5: Schematic of a Grassed Channel (Vermont Agency of Natural '
Resources, 2002)
�— CHANNEL LENGTH IS DIRECTLY PROPORTIONAL.TO ROADWAY LENGTH
PRETREATM81TMREBAY
(WHERE APPROPRIATE) '
OPOONAL CHEQ(OAN
RIPRAP. W W y, ay W W W W WW W W W W W
W W
W W � W W WWW W W WW WWW WW WW W
W W W W W W W W W W W
INFLOWW S' WW W W W WW HyWW Y' W WW WWSLOPE�7% W
-P W CWW LEN OM MAXINMIIW CHANNEL BOTTOM -►
W
W W W W W W W
W W W W W W W W W W W W W W
,IY W L W W W W V
reM
I
PLAN VIEW
SHOULDER- ,
ROADWAY
10 YFAR LEVEL _It,
- _ Alfa
I!14nl;lllyi U2YFAR LEVEL I
Jlllyll " _F VIII �
n1..: WO STORKnll-.^.A
— - VELOCITY LESS THAN 1.0 fps
IlflpI FOR i 'RAINFALL t
-M �-11A=11111yInIaTA_ -Int-111111I'Ivi�n I''
SECTION '
Grass channels should be inspected on an annual basis and just after storms of greater '
than or equal to the water quality storm event. Both the structural and vegetative '
components should be inspected and repaired. When sediment accumulates to a depth of
approximately 3 inches, it should be removed, and the Swale should be reconfigured to its
original dimensions. The grass in the channel should be mowed at least 4 times during '
the growing season. If the surface of the grass channel becomes clogged to the point that
standing water is observed on the surface 48 hours after precipitation events, the bottom
should be roto-tilled or cultivated to break up any hard-packed sediment, and then t
reseeded. Trash and debris should be removed and properly disposed of.
1
C-10 ,
' 6. Oil/Grit Separator
Oil/grit separators are pollution prevention devices that remove oil and sediment from
stormwater runoff and store them for safe and easy removal. They operate by employing
various physical or chemical separation methods, including gravity separation, filters,
coagulation/flocculation, and flotation. Typically, these devices contain a series of
chambers which serve to first trap floatables, and then employ gravity settling of
sediment. Oil and grease float to the top of a permanent pool of water, and ultimately get
' trapped in the second(separation) chamber. It is recommended that this practice is a
bypass structure. Storms that exceed the design capacity are bypassed by the structure,
minimizing the potential for resuspension of previously settled materials. Figure C-6
' below is an illustration of an oil/grit separator.
The estimated capital costs for these technologies vary and depend on the design
' capacity. Smaller units that are sized under 200 cubic feet will cost just under$10,000,
while larger units sized over 1,500 cubic feet can cost up to $80,000.
' Figure C-6: Schematic of an Oil/Grit Separator
INLET .. DISCHARGE
WATER OIL LAYER
SURFACE IN
' INLET SEPARATION
CHAMBER CHAMBER OUTLET
CHAMBER
' BAFFLE BAFFLE
' Maintenance burdens for these units are heavy and represent one of the larger drawbacks
to their application. Another limitation of these practices is their reported inability to
remove bacteria and nutrients. Because of this limitation, the devices are only specified
where no other BMP is feasible. Regular inspection, ranging from monthly to quarterly,
is required with routine removal of sand and oil. Further unplanned pump-outs are
required in the event of a large contaminant spill. Removal and disposal of sand and oil
generally costs approximately $400 per cleanout.
Cleanout is required once the stored volume reaches 15% of the device's capacity, or
immediately in the event of a spill. Maintenance intervals vary depending on the
application, but are recommended quarterly for the first year. Oils and sediments can be
' removed via accessible pipes and inspection ports.
' C-11
7. Sediment Forebay ,
A sediment forebay is an excavated pit designed to slow incoming stormwater runoff and '
settle suspended solids. It is primarily used to pretreat stormwater before continuing to
the primary water quality and quantity control BMP, typically stormwater basins and
wetlands. Frequent cleaning and inspection is essential to the effectiveness of this BMP. '
Sediment forebays rely primarily on settling for pollutant removal. Pollutants are only
removed when the sediments forebays are cleaned out.
The design criteria for sediment forebays should incorporate design features to make '
maintenance accessible and easy. They should not be any deeper than 3 to 6 feet with
side slopes not steeper that 3:1. A sediment depth marker makes inspection simple and '
identifies when sediment removal is due.
Sediment forebays usually are incorporated into stormwater wetland costs. For this '
project, sediment forebays were proposed for pretreatment of stormwater prior to existing
wetlands. The general cost would be similar to stormwater wetlands minus any planting
costs, however for the purpose of this report and maintaining a conservative cost '
estimate, sediment forebays were estimated with the same costs as for constructed
wetlands. This includes costs for clearing and grubbing, erosion and sediment control,
excavating, grading, and staking. Typical unit base costs for stormwater wetlands range ,
from $1.20 to $2.50 per cubic foot(CWP, 1998). Maintenance costs for wetlands are
estimated at 2% per year of the construction costs (CWP, 1998).
Maintenance is essential for proper operation of sediment forebays. Sediment forebays '
require routine sediment removal annually.
1
1
C-12
1
APPENDIX D
Selected BMP Sites
1
1 D-1 Subwatershed H-5
D-2 Subwatershed H-7
' D-3 Subwatershed H-9
' D-4 Subwatershed H-14
D-5 Subwatershed H-18
' D-6 Subwatershed H-22A
D-7 Subwatershed H-22B
1
1
1
1
11
APPENDIX D-1
Subwatershed H-5
1
1
1
1
1
1
1
1
' Peconic Bay Estuary Stormwater Retrofit Reconnaissance Inventory
' 1. Site Number: H-5
' 2. Location (Address and/or Parcel ID) End of Laurel Avenue
' 3. Description (preliminary assessment of most likely retrofit-quality, quantity, or both):
Retrofit for water quality and channel erosion protection; existing conditions include untreated
runoff to poorly flushed embayment and erosion gully.
' 4. Unique elements of retrofit (e.g., method of conveyance or stormwater diversion):
' Water quality swale and bioretention system
' 5. Date of Preliminary Survey: 9/12/05
' 6. Property Ownership (public or private): Public Roadway / Residential
7. Drainage Area: 0.71 acres
' 8. Approximate imperviousness (%): 63%
9. Adjacent Land Use (Possible conflicts): Private property, existing mature trees,
shoreline used as landing for fishing and kayaks.
1
10. Conflicts with Existing Utilities: None visible, all underground electric
1
' 11. Construction and Maintenance Access:
Excellent
12. Wetlands Present? ❑ Yes Q No
If yes, describe: However, near existing shoreline
' 13. Retrofit Volume Computations: 90% Rule: WOV = r(P) (Rv) (A)l / 12
Rv = 0.05+0.009(I)
WOV = r(P) ( 0.05+0.009(I)) (A)1 / 12
t WOV = r(1.2'D( 0.05+0.009(63))(0.71)1/ 12
WOV = 0.04 acre-ft= 1,908 cf
J:A4094 Peconic Bay Estuary`reports`.Hashamomuck PondAAppendix B H-SRetroGt_lnventory_Site H-d.doc
Horsley Witten Group
D-1
Peconic Bay Estuary Stormwater Retrofit Reconnaissance Inventory 1
14. Photo # H5-1 - H5-5 1
15. Additional Notes and/or Sketch Information: 1
Hasham�and 1
Long Creek
Existing Eroded Channel 1
+yi
Existing 1
24"Dia. Tree Existing Guard Rail
(Save)
Existing Gravel Driveway
Proposed I
=House 1
Bioretention private Property
Proposed 1
(-900 sf) Dry Swale (-700 sf)
Long Creek Drive
1 Proposed Grass Proposed Rip ProposedOverflow
Channel Rap Outlet Catch Basin
Long Creek Drive — — — — -r:-r rr -, — — — 11 1
I 1j r 111i1,
~!~fIll! !
T
~f~NflllM I •!•!!�!�!'! 1
I 1l�ftf4f11� `{! • S
!
rz
> I
Proposed I 1
Oil/Water
a Separator I
1
Proposed Overflow Catch Basin
*Note: Half of the roadway runoff will drain to a water quality swale and be treated in the proposed 1
Bioretention, the other half of the roadway will drain to a proposed dry swale. The overflow from both
BMPs will overflow to a proposed OiUWater separator and will be discharged to Long Creek. 1
16. Site Candidate for Further Investigation: 2 Yes ❑ No 1
J:\4094 Peconic Bay Estuary\reports\Hashamomuck PondWppendix B H-5\Retrofit Inventory_Site H-5.doc 1
Horsley Witten Group
D-2 1
' Peconic Bay Estuary Stormwater Retrofit Reconnaissance Inventory
1
' 15. Additional Notes and/or Sketch Information: Alternative
' Hasham�and
Long Creek
Existing Eroded Channel
Existing
24" Dia. Tree Existing Guard Rail
(Save)
Existing Gravel Driveway
' Proposed
Bioretention (-900 sf) : House
Private Property Proposed Dry
'
Long Creek Drive Swale (-700)
Proposed Guard Rail
(z 20 ft from existing Proposed Rip
1 end of roadway) Rap Outlet
Proposed
Long Creek Drive _ _ OWWater
T1 _ aejwUpr_ _
Gravel Driveway to °J
' Access Existing Q
Driveway & Boat 1
Launch a I FArea
. . . . . . . ,
,. . . . . . . .
Proposed Overflow Catch Basin
Remove Existing Asphalt Pavement
' *Note: Half of the roadway runoff will drain to a water quality swale and be treated in the proposed
Bioretention, the other half of the roadway will drain to a proposed dry swale. The overflow from both
' BMPs will overflow to a proposed Oil/Water separator and will be discharged to Long Creek.
16. Site Candidate for Further Investigation: 0 Yes ❑ No
' J:\4094 Peconic Bay Estuary\reports\Hashamomuck Pond\Appendix B H-5\Retrofit_lnventory_Site H-5.doc
' Horsley Witten Group
D-3
r
s ,
H-5
.Y
' t 1
r
LeLegend Source:Aerial Photo,NYS Once of Cyber Security&Critical
y Infrastructure Coordination,Spring 2004 i i�'1,i�1 `� IIIt '
n�M sns.aawsw
lureluywnlen wm �s1
Proposed BMP Drainage Areas Infiltration Catch Basin N
A Best Mangement Practices (BMP)Sites
Bioretention H-5 Site Location Hashamomuck Pond Watershed
Dry Swales Town of Southold
-Feet 1/19/06 EC
Grass Channel 150 JM094PemnicBay EstuarAGIMBMP_50es\ Figure D-1
H-5.m d
Hashamomuck • •
� • ._'+�! c r al.. '. o i lir �tiMsy" .t.
>. ` , �•..c e `+ ..ter • s
Northeast Corner
Laurel
Eroded Gully
H-5 West Side c�M
...,1 fn• -
Bioretention Location)
r1 ''
ED
�n
r �
Bioretention Location)
1
1
1
APPENDIX D-2
Subwatershed H-7
1
1
1
11
1
1
1
1
Peconic Bay Estuary Stormwater Retrofit Reconnaissance Inventory
' 1. Site Number: H-7
' 2. Location (Address and/or Parcel ID) Long Creek Drive
' 3. Description (preliminary assessment of most likely retrofit-quality, quantity, or both):
Retrofit for water auality and channel protection; existing conditions include untreated runoff
collecting into a catch basin which over tops the rim due to a clogged outlet pipe and overland
flows down an eroded gully.
4. Unique elements of retrofit (e.g., method of conveyance or stormwater diversion):
Bioretention with vegetated swales along both sides of roadway
5. Date of Preliminary Survey: 9/15/05
' 6. Property Ownership (public or private): Private except R.O.W.
7. Drainage Area: 6.1 acres
8. Approximate imperviousness (%): 23%
9. Adjacent Land Use (Possible conflicts): Private property easement required.
10. Conflicts with Existing Utilities: Water main near existing catch basin. Overhead
' power line on the other side of roadway. Existing large (2 ft dia.) trees nearby.
' 11. Construction and Maintenance Access:
Good
1
12. Wetlands Present? Yes ❑ No
If yes, describe: Down stream from the eroded gully and bordering the pond is some
wetland plants
t13. Retrofit Volume Computations: 90% Rule: WOV = r(P) (Rv) (A)1 / 12
Rv = 0.05+0.009(1)
WOV = r(P) ( 0 05+0.009(I)) (A)1 / 12
WOV = r(1.20 ( 0 05+0.009(23)) (6.1)1/ 12
WOV = 0 16 acre-ft = 6818 cf
14. Photo # 1-17-1 — 1-17-5
' J:\4094 Peconic Bay Estuary\reports\Hashainomuck Pond\Appendix C H-7\Retrofit Inventory Site 11-7.doc
' Horsley Witten Group
D-6
Peconic Bay Estuary Stormwater Retrofit Reconnaissance Inventory '
15. Additional Notes and/or Sketch Information:
Eroded
Long Creek Gully Hashamomuck Pond
Existing Tree '
(� 2 ft dia.) Proposed Riprap
for Overflow '
House Proposed '
Bioretention(1300 sf)
Existing Tree
. (� 2 ft dia.)
s > '
d
50 ft of roadway 200 ft of roadway > z '
Long Creek Dr. a
Existing
Hydrant I
,
Proposed y
Grass
Channel
Proposed Catch Bas '
4" Above Bottom Existing Infiltrating Catch Basin w/ 8 Quality Swale (to b
in. clogged overflow pipe (no visible Bioretention) '
outlet) & 2-3 in. clogged PVC outlet
(all to be removed)
*Note: Construct dry swales along both sides of the road to pretreat the runoff prior to being discharged into a
bioretention. Due to site constraints (existing large trees), the bioretention will have to be online. Riprap is
proposed at an overflow weir for storms greater than the first flush. Remove the existing catch basin and all
appurtenance.
16. Site Candidate for Further Investigation: Yes ❑ No
J:\4094 Peconic Bay Estuary\reports\Hashamomuck Pond\Appendix C H-7\Retroft Inventory_Site H-7.doc ,
Horsley Witten Group
D-7 ,
H-7
r 4Vr�' M
,
e
•Source:Aerial Photo,NYS Office of Cyber Security&Critical
Legend Infrastructure Coordination,Spring 2004 �Jt11S�c) ,� I1I21] �>fOUI i
E>`l
p >rvr'M1MPI'Mh!]
w.Rr«ywetw�.ppp
Proposed BMP Drainage Areas O Infiltration Catch Basin k
N Best Mangement Practices (BMP)Sites
F I° Bioretention LlOutlet Catchbasin Hashamown o Pond Watershed
Town of Southold
Grass Channel H Site Location greet 7119106 EC
150 JM094 PemnicBay EstuagAGIS1BMP_Sftes\ Figure D-2
H-7.natl
Hashamomuck • •
r ��� � �•• ate. �
• •i rV w
Outlet H Long Creek Dr. (West)
Aw
w
H-7 Long Creek Dr. (North)
7.1
H-7 Infiltratin Catch Basin Inlet
H-7 Lona Creek Dr. (East)
+.Or'..
1
1
1
' APPENDIX D-3
Subwatershed H-9
1
1
1
1
1
1
1
1
1
1
' Peconic Bay Estuary Stormwater Retrofit Reconnaissance Inventory
' 1. Site Number: H-g
' 2. Location (Address and/or Parcel ID) Long Creek Dr.
' 3. Description (preliminary assessment of most likely retrofit-quality, quantity, or both):
Existing detention pond with workino overflow. Catch basin and sediment forebav for limited
roadway area Aesthetics and water guality of groundwater in detention pond seems to be the
issue.
' 4. Unique elements of retrofit (e.g., method of conveyance or stormwater diversion):
Tree pruning over the pond area to increase light to pond surface Signs for pet owners to pick
' up after their pets• and wetland planting zones forebay to pond and replace outlet structure.
' S. Date of Preliminary Survey: 9/12/05
6. Property Ownership (public or private): Private
' 7. Drainage Area: 0.23 acres
' 8. Approximate imperviousness (%): 70%
9. Adjacent Land Use (Possible conflicts): Private land however owner seems eager
to help with restoration
' 10. Conflicts with Existing Utilities: Overhead power lines underground water main.
' 11. Construction and Maintenance Access:
Good
' 12. Wetlands Present? 0 Yes ❑ No
If yes, describe: Intermittent channel to existing detention pond with ground water
' influence.
13. Retrofit Volume Computations: The detention pond seems to be the right size.
90% Rule: WOV = r(P) (Rv) (A)1 / 12
Rv = 0.05+0.009(1)
' WOV = r(P) ( 0 05+0 009(I)) (A)1 / 12
WOV = r(1.2") ( 0.05+0.009(70)) (0.2311/ 12
WOV = 0.02 acre-ft = 681 cf
J:A4094 Peconic Bay Estuary,reports\HashanIOmuck Pond Appendix D H-91,Retrofit_lnventory Site H-9.doc
Horsley Witten Group
D-10
Peconic Bay Estuary Stormwater Retrofit Reconnaissance Inventory t
14. Photo # 119-1 - H9-7
Existing '
15. Additional Notes and/or Sketch Informatioi Overhead
Wire y r
o '
Connects to Upstream
ao
Proposed Grass n
Pond &Wetland Area Channel
(Possibly Perched) x '
House C7
Existing
Intermittent Proposed Catch Basin to ,
Channel
Discharge into Proposed 1
Sediment Forebay
Existing Foot
Bridge Existing 24-in
dia. CMP '
Extsting
Detention - Existing Catch
Existing Tree Line Over Pond Pond Basin
Replace Existing '
Proposed Clearing of the Tree Line to Overflow Structure
Expose Pond Surface to Sunlight w/Hooded Outlet
Proposed Wetlands Planting to 0
Improve Biodiversity and '
Create More Natural Habitat
Proposed Earthen Berm to Lengthen
Flow Path to Outlet
* Note: Degraded, standing water, probably in groundwater table. Neighbor notes that it gets significant flow '
during storms but does not look like it ever gets too high. A proposed sediment forebay is recommended to settle
out particles from the runoff from the section of roadway. Construct an earthen berm to prevent short circuiting '
to outlet. Cutback existing tree line to expose pond surface to sunlight. Introduce new wetland plants to improve
biodiversity. Replace existing overflow structure with a hooded outlet
16. Site Candidate for Further Investigation: ❑ Yes ❑ No '
J:\4094 Peconic Bay Estuary\reports\Hashamomuck Pond\Appendix D H-9\Retrofit_Inventory_Site H-9.doc ,
Horsley Witten Group
D-11 '
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it Source:Aerial Photo,NYS Office of Cyber Security&Critical H I �\
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Proposed BMP Drainage Areas El Outlet Catchbasin N
O Infiltration Catch Basin ^ Best Man Practices (BMP)Sites
n
Sediment Forebay on r ,\\V Hasharnonnumomuck Pond Watershed
Grass Channel H-9 Site Location
8 EC
Town of Southold
JM09
-Feel
too .\4094 Pa onic eay EstuaMGISS BMP_Skes\ Figure D-3
Hashamomuck Pond
zi
�r.
Outlet H-9 Long Creek Dr. (West)
� f 4
Eroded Gully H-9 Long Creek Dr. (East)
.3
H-9 Long Creek Drive (Catch Basin) H-9 Existing Pond
� r
Hashamomuck Pond '
v�
i
H-9 Existing Pond Outlet H-9 Yennocott Dr. (Catch Basin Inlet)
1
v 1
H-9 Yennocott Dr. (Park) H-9 Yennocott Dr. (Existing Pond) '
r •
V�It
H-9 Yennocott Dr. (East) H-9 Yennocott Dr. (North) '
1
1
D-14 '
' APPENDIX D-4
Subwatershed H-14
1
1
1
1
1
1
1
Peconic Bay Estuary Stormwater Retrofit Reconnaissance Inventory
1. Site Number: H-14
' 2. Location (Address and/or Parcel ID) Dons Way
3. Description (preliminary assessment of most likely retrofit-quality, quantity, or both):
tRetrofit for water quality.
4. Unique elements of retrofit (e.g., method of conveyance or stormwater diversion):
Grass channel along both sides of the roadway. New pavement may be required to direct
' flows accordingly. Bioretention at the end of the association for treatment prior to being
discharged into Hashamomuck Pond
5. Date of Preliminary Survey: 9/13/05
6. Property Ownership (public or private): Private
7. Drainage Area: 0.2 acre
8. Approximate imperviousness (%): 100%
9. Adjacent Land Use (Possible conflicts): At the end of the association there are two
very large trees
' 10. Conflicts with Existing Utilities: None observed
' 11. Construction and Maintenance Access:
Excellent
12. Wetlands Present? 0 Yes ❑ No
' If yes, describe: At the shore of Hashamomuck Pond there is some wetland plants and a
salt marsh.
13. Retrofit Volume Computations: 90% Rule: WOV = r(P) (Rv) (A)1 / 12
Rv = 0.05+0.009(1)
' WOV = r(P) ( 0.05+0.009(I)) (A)1 / 12
WOV = r(1.2") ( 0.05+0.009(100)) (0.2)1/ 12
WOV = 0.02 acre-ft = 621 cf
' 14. Photo # H14-NSA
J:A4094 Peconic Bay Estuary\reports Hashamomuck PondVtppendix F. H-14Utetro6t Imentory Site H-14.doc
' Horsley Witten Group
D-15
Peconic Bay Estuary Stormwater Retrofit Reconnaissance Inventory
15. Additional Notes and/or Sketch Information:
Dons Way
Terrace Cottag :; ❑
Colony)
Proposed Grass
Proposed Channel
Bioretention 0440 sf) Existing Trees
(save)
Hashamomuck Pond
16. Site Candidate for Further Investigation: 2 Yes El No
JA4094 Peconic Bay EstuaryVeports\Hashamomuck Pond\Appendix E H-14\Retrofit—Inventory Site H-14.doc
Horsley Witten Group
D-16
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P
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Infrastructure Coordination,Spring 2004 -Tr>i>Ic•c �� Iltt•n U1O 1
mane rdrx3sesm
huralxywY n.cu.
- Proposed BMP Drainage Areas O Infiltration Catch Basin N Best Mangement Practices (BMP)Sites
H-14 Site Location Hashamomuck Pond Watershed
Grass Channels Town of Southold
Bioretention Feet 7114 94 EC
75 J:M094PeconicSayEstuaMGIS\BMP_Sites\ Figure D-4
H-7Omxd
I�
' APPENDIX D-5
Subwatershed H-18
1
1
1
1
1
1
1
1
' Peconic Bay Estuary Stormwater Retrofit Reconnaissance Inventory
1. Site Number: H-18
' 2. Location (Address and/or Parcel ID) Bayview Avenue
' 3. Description (preliminary assessment of most likely retrofit-quality, quantity, or both):
Retrofit for quality
4. Unique elements of retrofit (e.g., method of conveyance or stormwater diversion):
There is an existing leaching pit with 3'x3' grate. Propose water quality swales on both sides
of the roadway and overflow into existing leaching pit.
5. Date of Preliminary Survey: 9/12/05
' 6. Property Ownership (public or private): Private with existing drainage easement
7. Drainage Area: 2.3 acres
8. Approximate imperviousness (%): 26%
9. Adjacent Land Use (Possible conflicts): None
10. Conflicts with Existing Utilities: Existing sewer, overhead electric, private property
' 11. Construction and Maintenance Access:
Excellent
12. Wetlands Present? ❑ Yes 0 No
' If yes, describe:
' 13. Retrofit Volume Computations: 90% Rule: WOV = r(P) (Rv) (A)1 / 12
Ry = 0.05+0.009(I)
' WOV = F(P). ( 0.05+0.009(I)) (A)1 / 12
WOV = r(1.2'D ( 0.05+0.009(26)) (2.3)1/ 12
WOV = 0.07 acre-ft = 2.808 cf
J:A4094 Peconic Bay EstuaryvreportsyHashamomuck Pond\Appendix F H-18\Retrofit Inventory Site H-18.doc
' Horsley Witten Group
D-18
Peconic Bay Estuary Stormwater Retrofit Reconnaissance Inventory '
14. Photo # H18 '
15. Additional Notes and/or Sketch Information: '
Existing Infiltration
Pit w/ 3'x3' Metal '
Grate
Proposed Oil/Grit Separator o '
Existing Overhead
o Wire
o '
�— 400 ft > 480 ft
Bayview ve.
Proposed Dry Swale
Existing Catch Basin (to be remove
(total —2600sf) Proposed Catch Basin
*Note: Contruct dry swales to pretreat roadway drainage, provide culvert at driveway crossings to '
convey flows to overflow catch basins. All flow will be collected at an oil/grit separator manhole
prior to discharge in the existing infiltration pit. '
16. Site Candidate for Further Investigation: Yes ❑ No '
J:\4094 Peconic Bay Estuary\reports\Hashamomuck Pond\Appendix F H-18Tetrofit_Inventory_Site H-18.doc '
Horsley Witten Group
D-19 ,
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Legend Infrastructure Coordination,Spring 2004 H'1t,k% \` iflcn Group r'
r��+.�r�a3lcnno
r..•duy+aan.wm-��
- Proposed BMP Drainage Areas • Outfalls A
NBest Mangement Practices (BMP) Sites
Dry Swales O Infiltration Catch Basin Hashamomuck Pond Watershed
Town of Southold
\/ Stormdrain Conveyance Systems H-18 Site Location -Feet „11,06 EC
150J:�40s iBay estuaMClsaMP_sitesl Figure D-5
H-18 mxd
Hashamomuck Pond
1
01
•I; w
i
H-18 Inlet Grate to Infiltration Pit
1
' D-21
APPENDIX D-6
Subwatershed H-22A
1
1
1
1
1
1
1
1
1
' Peconic Bay Estuary Stormwater Retrofit Reconnaissance Inventory
' 1. Site Number: H-22A
t2. Location (Address and/or Parcel ID) Grove Road
' 3. Description (preliminary assessment of most likely retrofit-quality, quantity, or both):
Retrofit for water quality
' 4. Unique elements of retrofit (e.g., method of conveyance or stormwater diversion):
Micropool at outfall location with stone check dam. Micro-bioretention
' 5. Date of Preliminary Survey: 9/12/05
6. Property Ownership (public or private): Public in R.O.W.
7. Drainage Area: 4.48 acres
' 8. Approximate imperviousness (%): 20.1%
9. Adjacent Land Use (Possible conflicts): Private Property
' 10. Conflicts with Existing Utilities: Overhead power lines public water main
' 11. Construction and Maintenance Access:
Good
12. Wetlands Present? 0 Yes ❑ No
If yes, describe: Existing wet channel that is tidally influenced at the outfall location.
13. Retrofit Volume Computations: 90% Rule: WOV = r(P) (Rv) (A)1 / 12
Rv = 0.05+0.009(I)
WOV = r(P) ( 0.05+0.009(I)) (A)1 / 12
WOV = r(1.2") ( 0.05+0.009(20)) (4.5)1/12
' WOV = 0.1035 acre-ft= 4500 cf
J:A4094 Peconic Bay Estuary\reports\Retrofit Inventory\Hashamomuck. Pond\Retrofit_Inventorv_Site 11-22A.doc
Horsley Witten Group
D-22
Peconic Bay Estuary Stormwater Retrofit Reconnaissance Inventory '
14. Photo # H22A-1 & H22A-2 ,
15. Additional Notes and/or Sketch Information: '
* Note: Alter existing vegetated channel to have a micropool to help settle out sediments and '
construct stone check dams to slow the flow down and prevent erosion. Construct a small scale
bioretention system (Micro-Bioretention) with a stone curtain to settle out sediments prior to being '
treated in the filter media. The overflow will drain into the existing drainage network.
G7 ,
0
a '
Existing
Catchbasin '
Existing Grated Manhole
Proposed Grove Rd.
Overflow 3' high—3" diameter '
Steel Bollard
Proposed Micro-Bio Inlet w/ ,
Stone Curtain (--1300 sfl Existing 36" CMP '
Outfall
/12"f i
Maple Ln.
y+
Transition Pavement
Proposed Micropool ;
to Match New Work ;r•
(Sediment Forebay—330 sf) '
Proposed Wetland Existing Vegetated
Plantings, to be Added Channel
imill
Creek Dr. (Tidal Influenced) ,
Proposed Stone I I
Check Dam '
16. Site Candidate for Further Investigation: Yes ❑ No
JA4094 Peconic Bay EstuaryVeports\Retrofit Inventory\Hashamomuck_Pond\Retrofit_Inventory_Site H-22A.doc '
Horsley Witten Group
D-23 '
J
A
y
I
H-22A ,
71444
�F Source:Aerial Photo,NYS Office of Cyber Security&Critical
Legend Infrastructure Coordination,Spring 2004
rr�,w sia-rvvhavc v
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- Proposed BMP Drainage Areas • Outfalls H-22A Site Location N
Best Mangement Practices (BMP)Sites
Micro-bio Inlet U Outlet Catchbasin
Hashamoshamomuck Pond Watershed
Sediment Forebay
O Infiltration Catch Basin Town of Southold
/� � Feet 7111106 ec
/ �/ Stormdrain Conveyance Systems ■ Drywells 150 H2�Pa nicBayP uaMGIS\SMP_SHes\ Figure D-6
' Hashamomuck Pond
' H-22A Existing Vegetated Channel
(Northwest)
' H-22A Existing Vegetated Channel (South)
1
1
' D-25
1
1
1
' APPENDIX D-7
Subwatershed H-22B
1
1
1
1
1
1
1
1
1
' Peconic Bay Estuary Stormwater Retrofit Reconnaissance Inventory
' 1. Site Number: H-228
' 2. Location (Address and/or Parcel ID) Grove Road
3. Description (preliminary assessment of most likely retrofit-quality, quantity, or both):
Retrofit fro water auality
4. Unique elements of retrofit (e.g., method of conveyance or stormwater diversion):
Dry swale alona roadway. Conveyance system into existing infiltrating catch basin overflow to
' an oil/water separator and discharge into Hashamomuck Pond
' 5. Date of Preliminary Survey: 9/12/05
6. Property Ownership (public or private): Public in R. W.
7. Drainage Area: 1.3 acres
' 8. Approximate imperviousness (%): 25%
9. Adjacent Land Use (Possible conflicts): Private
10. Conflicts with Existing Utilities: Possible underground water main
t11. Construction and Maintenance Access:
Good
t
' 12. Wetlands Present? ❑ Yes 0 No
If yes, describe:
13. Retrofit Volume Computations: 90% Rule: WOV = r(P) (Rv) (A)1 / 12
Rv = 0.05+0.009(1)
WOV = r(P) ( 0.05+0.009(l)) (A)1 / 12
WOV = r(1.2") ( 0.05+0.009(25)) (1.3)1/12
' WOV = 0.04 acre-ft = 1.557 cf
7`4094 Peconic Bay Estuary\reports\Hashamomuck PondAAppendix H H-22B\Retrofit. Inventory_Site H-22B.doc
' Horsley Witten Group
D-26
Peconic Bay Estuary Stormwater Retrofit Reconnaissance Inventory ,
14. Photo # '
15. Additional Notes and/or Sketch Information: '
Grove Road '
Proposed Dry Swales on '
Both Sides of the
Roadway (--1400 s
210 ft
Proposed Drainage
Outlet to be Aligned '
Between Neighboring
Houses
-
Existing Infiltrating
Catch Basin
(to be removed)
Proposed Oil/Water '
Separator
80 ft '
*Note: Proposed dry swales along both sides of roadway to pre-treat and convey runoff to an overflow '
grate. Provide culverts at driveway crossings to continue flow. The overflow grate is elevated 4-inch
above the bottom of swale to promote infiltration of the first flush storm events. The overflow will be
discharged directly into Hashamomuck Pond, this will help resolve some localized flooding during large '
storm events. Remove the existing infiltrating catch basins.
16. Site Candidate for Further Investigation: Q Yes ❑ No '
J:\4094 Peconic Bay Estuary\reports\Hashamomuck Pond\Appendix H H-22B\Retrofit_Inventory_Site H-22B.doc '
Horsley Witten Group
D-27 '
'r.
f
e
S
I:
♦Source:Aerial Photo,NYS Office of Cyber Security&Critical
Legend Infrastructure Coordination,Spring 2004
�`r,T cl4-Pit{.flt
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- Proposed BMP Drainage Areas • Outfalls H•226 Site Location of
® Best Mangement Practices (BMP)Sites
11Dry Swales Outlet Catchbasin Hashamoashamomuck Pond Watershed
Town of Southold
Stormdrain Conveyance Systems O Infiltration Catch Basin Feet 7112106 EC
too JAOWPeoonicBay esmarynGISNBMP_saes' FigureD-7
H-22B.mxd
1
I, 1
' APPENDIX E
Unified Subwatershed and Site Reconnaissance
1
1
1
1
1
1
1
1 Streets and Storm Drains SSD
' Watershed: Hashamomuck Subwatershed: H-4 Unique Site ID: H-4
Date: 09/ IN 05 Assessed By: T.W. &N.P. Camera ID: Cannon
tMap Grid Rain in Last 24 Hours ❑ Y ® N Pic#
A. Location
' Al. Street names or neighborhood surveyed: Drive
Lone Creek Drive&Park Avenue
A2.Adjacent land use: ®Residential❑Commercial ❑ Industrial ❑ Institutional
❑Municipal ❑ Trans ort-Related
' A3.Corresponding HSI or NSA field sheet? If so,circle HSI o NS d record its Unique Site ID here H=4
t B. Street Conditions
Bl. Road Type: ❑ Arterial ❑Collector ® Local ❑ Alley ❑ Other:
B2.Condition of Pavement: ®New ❑Good ❑Cracked ❑ Broken
' B3.Is on-street parking permitted ® Y ❑N If yes, approximate number of cars per block: 0
B4.Are large cul-de-sacs present? ❑Y ®N
' B5.Is trash present in curb and gutter?If so, Index Rating for Accumulation in Gutters
use the index to the right to record amount. Clean Filth
Sediment ❑ 1 ❑ 2 ❑3 ❑4 ❑ 5
'
Organic Material ❑ 1 ❑ 2 [:13 ❑4 ❑ 5
Litter El El El El El
C. Storm Drain Inlets and Catch Basins
Cl.Type of storm drain conveyance: ®open ❑enclosed ❑mixed
C2.Percentage of inlets with catch basin rage: 100%❑N/A(only I CB in entire neighborhood)
Sample 1-2 catch basins per NSAIHSI C3.Catch basin#1 C4.Catch basin#2
Latitude ° 0—1 „
Longitude -C-, -e -n
LMK#
' Picture# 4
Current Condition ❑Wet ® Dry ❑Wet ❑Dry
Condition of Inlet ®Clear❑Obstructed ❑Clear❑Obstructed
' Litter Accumulation ❑Y ®N ❑Y ❑N
Organics Accumulation ®Y ❑N ❑Y ❑N
Sediment Accumulation ®Y ❑N ❑Y ❑N
Sediment Depth in feet ft. ft.
' Water Depth None ft. ft.
Evidence of oil and greaseN ❑Y [_1N
Sulfur smell ❑Y ®N ❑Y ❑N
' Accessible to vacuum truck ®Y ❑ N I ❑Y ❑ N
D.Non-Residential Parking Lot(>2 acres)
Dl.Approximate size: acres
D2.Lot Utilization: ❑Full ❑About half full ❑ Empty
D3.Overall condition of Pavement: ❑ Smooth(no cracks) ❑Medium(few cracks) ❑Rough(many cracks)
❑Very Rough(numerous cracks and depressions)
tD4.Is lot served by a storm water treatment practice? LJ Y ❑N If yes,describe:
D5.On-site retrofit potentiaL El Excellent 0 Good D Poor
' E-1
Streets and Storm Drains SSD 1
E.Municipal Pollutant Reduction Strategies 1
El.Degree of pollutant accumulation in the system: ❑ High ❑Medium ❑Low ❑ None
E2.Rate the feasibility of the following pollution prevention strategies:
Street Sweeping: ®High ❑Moderate ❑ Low 1
Storm Drain Stenciling: ❑High ❑Moderate ®Low
Catch Basin Clean-outs: ®High ❑Moderate ❑ Low
Parking Lot Retrofit Potential: ❑High ❑Moderate ® Low 1
Catch Basin Sketches
#1 #2
1
1
1
1
Notes: 1
1
1
1
1
� 1
1
i
1
1
E2 1
' Pervious Area Assessment E
PAA
Watershed:Hashomomuck Subwatershed:H-9 Unique Site ID:H-9
Date:09/13/05 Assessed By:T.W.&N.P. Camera ID: Cannon Pic#: 9&10
' Map Grid: Lat_° "Long—.—, LMK#
A.Parcel Description
' Size: 1 acre(s) Access to site(check all that apply): ®Foot access ®Vehicle access ®Heavy equipment access
Ownership: ❑Private ❑Public Current Management: ❑ School ❑Park ❑Right-of-way ❑Vacant land
❑Other(please describe)
Contact Information:
Connected to other pervious area? ®Y ❑N If yes,what type? ❑Forest ®Wetland❑Other
Estimated size of connected pervious area: 50 acre(s) Record Unique Site ID of connected fragment:
MNANT
FOREST WETLAND
B.Current Vegetative Cover B. Current Vegetative Cover
Bl.Percent of forest with the following canopy coverage: Bl.%of wetland with following vegetative zones:
Open % Partly shaded_% Shaded % Aquatic:
*Note-these should total 100% Emergent:
' B2.Dominant tree species: Forested:
*Note-these should total 100%
B3.Understory species: B2.Dominant species:
B4.Are invasive species present? ❑Y ❑N B3.Are invasive species present? ❑Y ❑N
❑Unknown ❑Unknown
If yes, %of forest with invasives: If yes, %of wetland with invasives:
Species: Species:
' C.Forest Impacts C.Wetland Impacts
Cl.Observed Impacts(check all that apply): Animals Cl.Observed Impacts(check all that apply): Lj Animals
❑Clearing/encroachment ❑Trash and dumping ❑ ❑Clearing/encroachment ❑Trash and dumping ❑
Storm water runoff ❑Other Storm water runoff ❑Hydrologic impacts ❑Other
D.Notes D. Notes
E.Initial Recommendation
❑ Good candidate for conservation/protection
❑Potential restoration candidate
❑ Poor restoration or conservation candidate
' E-3
Pervious Area Assessment pAA
OUS c '
A.Current Vegetative Cover
Al.Percent of assessed surface with: '
Turf 8LO-0/0 Other Herbaceous 5% None(bare soil) % Trees 5 % Shrubs 10 %Other—%(please describe):
*Note-these should total 100%
A2.Turf: Height:< 1 inches Apparent Mowing Frequency: Z Frequent Lj Infrequent No-Mow Lj Unknown '
Condition check all that apply): Thick/Dense ❑ Thin/Sparse ❑ Clumpy/Bunchy Clumpy/Bunch ® Continuous Cover
A3.Thickness of organic matter at surface: inches
A4.Are invasive species present? ❑Y ❑N ®Unknown If yes,%of site with invasives: '
Species:
B.Impacts
Bl.Observed Impacts(check all that apply): Lj Soil Compaction Erosion Trash and Dumping '
❑Poor Vegetative Health ❑Other(describe):
C.Reforestation Constraints
Cl.Sun exposure: Z Full sun Partial sun❑ Shade ❑ Unknown ,
C2.Nearby water source?®Y ❑N ❑Unknown
C3.Other constraints: 0 Overhead wires Z Underground Utilities Pavement Buildings '
❑Other(please describe):
D.Notes
E.Initial Recommendation '
®Good candidate for natural regeneration
®May be reforested with minimal site preparation
❑May be reforested with extensive site preparation '
❑Poor reforestation or regeneration site
Trees '
Trees
Open Park Area
Yennecott Drive '
N
Pond '
E-4 '
' Neighborhood Source Assessment NSA
Watershed: Hashamomuck Subwatershed: H-14 Unique Site ID:H-14
' Date:09/13/05 Assessed By: T.W. &N.P. Camera ID: Cannon Pic#: 11
A. Neighborhood Characterization
' Neighborhood/Subdivision Name:Terrace Cottage Colony Neighborhood Area(acres)
If unknown,address(or streets)surveyed:Don's Wav
Homeowners Association?❑Y ❑N ❑Unknown If yes,name and contact information:
' Residential (circle average single family lot size):
❑ Single Family Attached(Duplexes,Row Homes) <'/s '/s Y4 '/3 '/3 acre ❑Multifamily(Apts,Townhomes,Condos)
®Single Family Detached CD V4 '/2 1 >1 acre ❑Mobile Home Park
Estimated Age of Neighborhood: 40 years Percent of Homes with Garages: 0 % With Basements 0% INDEX*
Sewer Service? ❑Y ON •
Index of Infill,Redevelopment,and Remodeling ®No Evidence ❑<5%of units❑ 5-10%E3>10% O
Record percent observed for each of the following indicators, Percentage Comments/Notes
depending on applicability and/or site complexity
B.Yard and Lawn Conditions All the same cottages
Bl.%of lot with impervious cover 30
' B2. %of lot with grass cover 55 •
B3. %of lot with landscaping(e.g.,mulched bed areas) 10
B4. %of lot with bare soil 5 •
' *Note:Bl through B4 must total 100%
B5. %of lot with forest canopy 75
' B6.Evidence of permanent irrigation or`hon-target"irrigation No O
High: O
' B7.Proportion of total neighborhood turf lawns with following Med:
management status:
Low: ✓
'
B8.Outdoor swimming pools?❑Y ON❑ Can't Tell Estimated#4 0 —
B9.Junk or trash in yards? ❑Y®N❑Can't Tell O
C. Driveways,Sidewalks,and Curbs
Cl. %of driveways that are impervious ❑N/A 0
C2. Driveway Condition®Clean ❑ Stained ❑Dirty ❑Breaking up 0 Dirt •
' C3. Are sidewalks present? ❑ Y ®N If yes,are they on one side of street❑or along both sides❑
- - - - -----------------------------------------------------------------------------------------
❑ Spotless ❑ Covered with lawn chppings/leaves ❑Receiving non-targetirrigation 0
----------------------------------------------------------------------------------------------------------------------- -......--•---
What is the distance between the sidewalk and street? ft. Q
' Is pet waste present in this area? ❑Y ❑N❑N/A 0
C4. Is curb and gutter present?_-- Y__�N _Ifya,checkallthatapply:_______--------------------------------
--------••--
' ❑Clean and Dry [:]Flowing or standing water El Long-term car parking El Sediment O
----- -- - ------ --- --------- --------- - -------------
❑Organic matter,leaves,lawn clippings ❑Trash,litter,or debris ❑Overhead tree canopy Q
* INDEX: O denotes potential pollution source; Q denotes a neighborhood restoration opportunity
E-5
Neighborhood Source Assessment
D. Rooftops
DI.Downspouts are directly connected to storm drains or sanitary sewer No ♦ Q '
D2.Downspouts are directed to impervious surface No
Downspouts
D3.Downspouts discharge to pervious area ,
D4.Downspouts discharge to a cistern,rain barrel,etc.
*Note: Cl through C4 should total 100%
D5. Lawn area present downgradient of leader for rain garden? ❑ Y❑N 0 '
E.Common Areas
El_ Storm drain inlets? El ®N If yes, are they stenciled? ❑Y❑N Condition: El Clean El Dirty
---------------------------------------------------------------------- ----
Catch basins inspected? ❑ Y ❑N If yes,include Unique Site ID from SSD sheet: Q
E2. Storm water pond? ❑Y®N Is it a❑wet pond or❑dry pond? Is it overgrown?❑Y ❑N O
What is the estimated and area? ❑<1 acre [:] about 1 acre E]> 1 acre '
E3. Open Space? [:1 Y ®N If yes, is pet waste present? ❑ Y El dumping? E]Y E]N O
------------------....._----—---------------------_.--------------------------
Buffers/floodplain present: ❑Y ❑N If yes,is encroachment evident?❑ Y ❑ N
F.Initial Neighborhood Assessment and Recommendations '
Based on field observations,this neighborhood has significant indicators for the following: (check all that apply) •
❑ Nutrients ❑ Oil and Grease ❑ Trash/Litter❑ Bacteria® Sediment ❑ Other '
Recommended Actions Describe Recommended Actions:
Specific Action
❑ Onsite retrofit potential?
❑ Better lawn/landscaping practice?
❑ Better management of common space?
❑ Pond retrofit? t
❑ Multi-family Parking Lot Retrofit?
❑ Other action(s)
Initial Assessment '
NSA Pollution Severity Index
❑ Severe (More than 10 circles checked) '
❑High (5 to 10 circles checked)
®Moderate(Fewer than 5 circles checked)
❑None (No circles checked) '
Neighborhood Restoration Opportunity Index
❑High (More than 5 diamonds checked) '
® Moderate(3-5 diamonds checked)
❑ Low (Fewer than 3 diamonds checked)
1
E-6 ,
' Neighborhood Source Assessment NSA
' NOTES:
1
I
1
E-7
Neighborhood Source Assessment
Watershed: Hashamomuck Subwatershed: H-9 Unique Site ID: H-9 ,
Date: 09/13/05 Assessed By: T.W. &N.P. Camera ID: Cannon Pic#: 5-7 '
A. Neighborhood Characterization
Neighborhood/Subdivision Name: Neighborhood Area(acres) '
If unknown,address(or streets) surveyed: Yennecott Drive
Homeowners Association? ❑ Y ❑ N ® Unknown If yes,name and contact information:
Residential (circle average single family lot size):
❑ Single Family Attached(Duplexes,Row Homes) </s ye y, '/3 '/3 acre ❑ Multifamily(Apts,Townhomes, Condos)
® Single Family Detached <y, '/,Q 1 >1 acre ❑Mobile Home Park
Estimated Age of Neighborhood: 30+yearsPercent of Homes with Garages: 100 % With Basements 100% INDEX* '
Sewer Service? [-IY ®N 0
Index of Infill,Redevelopment,and Remodeling ® No Evidence ❑ <5%of units❑ 5-10%❑>10% 0 '
Racm4pareW obserw dfor eack afAtfa&wng.isndicdws,
on qWficablift amftt Ate I pwoe *
B.Yard and Lawn Conditions Picture# 5 6 7 '
Bl.%of lot with impervious cover 12 35 30
B2. %of lot with grass cover 0 60 30
133. %of lot with landscaping(e.g.,mulched bed areas) 10 5 5 ♦ ,
B4. %of lot with bare soil 0 0 0 0
*Note.BI through B4 must total 100% 78 0 8 '
B5. %of lot with forest canopy 80 20 30 0
B6.Evidence of permanent irrigation or"non-target"irrigation N Y N '
High: 20 0
B7.Proportion of total neighborhood turf lawns with following Med: 60
management status: ,
Low: 20
B8.Outdoor swimming pools?MY ❑N❑Can't Tell Estimated#11/27 0
B9.Junk or trash in yards? ❑Y ® N ❑ Can't Tell 0 '
C. Driveways, Sidewalks,and Curbs
C1. %of driveways that are impervious ❑ N/A 100 '
C2. Driveway Condition®Clean ❑ Stained ❑Dirty ❑ Breaking up 0
C3. Are sidewalks present? ❑ Y ❑ N If yes,are they on one side of street❑ or along both sides ❑
-------------------------------------- -
-------------------------------- -----
-E] Spotless ❑ Covered with lawn clippings/leaves ❑ Receiving `non-targetirrigation 0
What is the distance between the sidewalk and street? ft. 0
--------------------------------------------------------------------------------------------------------------------------- -------------
Is pet waste present in this area? ❑ Y ❑ N❑ N/A 0 '
C4. Is curb and gutter present? ❑ Y ® N If yes,check all that apply: - -- -- - --
-------------
❑ Clean and Dry ❑ Flowing or standing water E-1Long-termcar parking El Sediment 0
----------------------------------------------—-
-----
❑ Organic matter,leaves,lawn clippings ❑Trash, litter,or debris ❑ Overhead tree canopy 0
* INDEX: 0 denotes potential pollution source; 0 denotes a neighborhood restoration opportunity
E-8 '
' Neighborhood Source Assessment NSA
' D. Rooftops
' Dl.Downspouts are directly connected to storm drains or sanitary sewer No Q O
D2.Downspouts are directed to impervious surface 50%
D3.Downspouts discharge to pervious area 50%
D4.Downspouts discharge to a cistern,rain barrel,etc. No
*Note: Cl through C4 should total 100%
' D5. Lawn area present downgradient of leader for rain garden? ® Y❑N
E.Common Areas
El. Storm drain inlets? ®Y❑N If yes,are they stenciled? ❑ Y®N Condition: ❑Clean ® Dirty
Catch basins inspected? ® Y ❑N If yes, include Unique Site ID from SSD sheet:HH=9 •
E2. Storm water pond? ❑ Y®N Is it a❑wet pond or❑ dry pond? Is it overgrown?❑ Y ❑N O
What is the estimated pond area? ❑<1 acre ❑ about 1 acre ❑ > 1 acre
E3. Open Space?® Y El-N If yes,is pet waste present? ® Y ❑ N dumping? ❑Y ® N O
------------------------------ ------------------------------------------------------------------------
-------------------- --------------
Buffers/floodplain present: ®Y ❑N If yes,is encroachment evident?❑ Y ® N
' F.Initial Neighborhood Assessment and Recommendations
Based on field observations,this neighborhood has significant indicators for the following: (check all that apply) •
' ® Nutrients ❑ Oil and Grease ❑ Trash/Litter❑ Bacteria❑ Sediment ❑ Other
Recommended Actions Describe Recommended Actions:
Specific Action
' ® Onsite retrofit potential? Lawn care education, street sweeping, catchbasin cleanout,
® Better lawn/landscaping practice? swale retrofits
❑ Better management of common space?
❑ Pond retrofit?
❑Multi-family Parking Lot Retrofit?
❑ Other action(s)
Initial Assessment
NSA Pollution Severity Index
❑ Severe (More than 10 circles checked)
®High (5 to 10 circles checked)
❑Moderate(Fewer than 5 circles checked)
' ❑ None (No circles checked)
Neighborhood Restoration Opportunity Index
❑ High (More than 5 diamonds checked)
® Moderate(3-5 diamonds checked)
❑ Low (Fewer than 3 diamonds checked)
' NOTES:
' E-9
Neighborhood Source Assessment
Watershed: Hashamomuck Subwatershed: H-4 Unique Site ID: H-4 '
Date: 09/13/05 1 Assessed Bv: T.W. &N.P. Camera ID: Cannon Pic#: '
A. Neighborhood Characterization
Neighborhood/Subdivision Name: Neighborhood Area(acres) '
If unknown,address(or streets)surveyed:Lone Creek Drive&Park Avenue
Homeowners Association?❑ Y ❑ N ® Unknown If yes,name and contact information:
Residential (circle average single family lot size):
❑ Single Family Attached(Duplexes,Row Homes) <'/8 '/8 ''A '/s '/s acre ❑Multifamily(Apts,Townbomes,Condos) '
® Single Family Detached <'/4 '/4 'h 1 ® acre ❑ Mobile Home Park
Estimated Age of Neighborhood:_A_years Percent of Homes with Garages: 100 % With Basements 100% INDEX* '
Sewer Service? ❑ Y ® N
Index of Infill,Redevelopment,and Remodeling ®No Evidence ❑ <5%of units❑ 5-10%❑>l0% O
Record perci absared for each 'tl�tfoB AWWW3 INkicistAto '
6*8
B.Yard and Lawn Conditions Picture# 1 2 3 '
Bl.%of lot with impervious cover 30 20 40
132. %of lot with grass cover 25 78 20 0
133. %of lot with landscaping(e.g.,mulched bed areas) 5 2 4 ♦ '
B4. %of lot with bare soil 0 0 0 0
*Note:BI through B4 must total 100% 100 100 100 '
B5. %of lot with forest canopy 0 0 20
B6.Evidence of permanent irrigation or"non-target'irrigation Y Y Y '
High: 100
B7.Proportion of total neighborhood turf lawns with following Med:
management status: '
Low:
B8.Outdoor swimming pools? ®Y ❑N ❑ Can't Tell Estimated#4
B9.Junk or trash in yards? ❑ Y ®N❑Can't Tell Q '
C. Driveways, Sidewalks,and Curbs
Cl. %of driveways that are impervious ❑ N/A 100 '
C2. Driveway Condition® Clean ❑ Stained ❑ Dirty ❑Breaking up Q
C3.-Are sidewalks present? ❑Y ® N If yes,are they on oneside of t❑streeor along both sides❑
❑ [I '
❑ Spotless Covered with lawn clippings/leaves Receiving `non-target irrigation
- ----- ---- - --—--- ----- - - - --
What is the distance between the sidewalk and street? ft. Q
------------------------—---------------------------------------------------------- - ------------ -------------
Is pet waste present in this area? ❑ Y ❑N❑N/A Q '
C4. Is curb and gutter present?__ ❑ Y ®NIf yes,check all that apply:
-------------
❑ Clean and Dry ❑ Flowing or standing water ❑ Long-term car parking ❑ Sediment Q
-..-----—-—----—-----------------------------------------------------------------—--——-
❑ Organic matter,leaves,lawn clippings ❑ Trash, litter, or debris ❑ Overhead tree canopy Q '
* INDEX: 0 denotes potential pollution source; 0 denotes a neighborhood restoration opportunity
E-10 '
' Neighborhood Source Assessment NSA
' D. Rooftops
' DI.Downspouts are directly connected to storm drains or sanitary sewer No Q Q
D2.Downspouts are directed to impervious surface 50%
' D3.Downspouts discharge to pervious area 50%
D4.Downspouts discharge to a cistern,rain barrel,etc. No
"Note: C1 through C4 should total 100%
' D5. Lawn area present downgradient of leader for rain garden? ® Y❑N
E.Common Areas
El. Storm drain inlets? ❑ Y❑N If yes,are they stenciled? ❑Y ❑N Condition: ❑Clean ❑Dirty Q
---------------------------------------------------------------------------------------------------------------- --------------
Catch basins inspected? ❑Y ❑N If yes, include Unique Site ID from SSD sheet: O
E2. Storm water pond? ❑ Y❑N Is it a❑wet pond or❑dry pond? Is it overgrown? ❑Y ❑N O
' What is the estimated pond area. ❑<1 acre ❑ about 1 acre ❑ > 1 acre
E3. Open Space? ❑ Y ❑N If yes, is pet waste present? ❑Y ❑N dumping? ❑ Y ❑N O
--------------------------------------------------------------------------------------------------------------------------- --------------
Buffers/floodplain present: ❑ Y ❑N If yes,is encroachment evident?❑ Y ❑N
' F. Initial Neighborhood Assessment and Recommendations
Based on field observations,this neighborhood has significant indicators for the following: (check all that apply)
® Nutrients ❑ Oil and Grease ❑ Trash/Litter❑ Bacteria❑ Sediment ❑Other
' Recommended Actions Describe Recommended Actions:
Specific Action
' ® Onsite retrofit potential? -Rain gardens can be constructed at the end of downspouts
® Better lawn/landscaping practice? easily.
❑ Better management of common space? -Education on lawn and landscaping practices.
' ❑ Pond retrofit?
❑Multi-family Parking Lot Retrofit?
❑ Other action(s)
Initial Assessment
NSA Pollution Severity Index
❑ Severe (More than 10 circles checked)
®High (5 to 10 circles checked)
❑Moderate(Fewer than 5 circles checked)
❑None (No circles checked)
Neighborhood Restoration Opportunity Index
❑High (More than 5 diamonds checked)
®Moderate(3-5 diamonds checked)
❑Low (Fewer than 3 diamonds checked)
' NOTES:
E-11
Streets and Storm Drains
Watershed: Hashamomuck Subwatershed: H-9 Unique Site ID: H-9
Date: 09/ IN 05 Assessed By: T.W. &N.P. Camera ID: Cannon
Map Grid Rain in Last 24 Hours ❑ Y ®N Pic# 8 '
A.Location
Al.Street names or neighborhood surveyed:Drive '
Yennecoh Drive
A2.Adjacent land use: ®Residential❑ Commercial ❑Industrial ❑ Institutional '
❑Municipal ❑Trans ort-Related
A3.Corresponding HSI or NSA field sheet?If so, circle HSI o NS d record its Unique Site ID here HH=9
B. Street Conditions '
Bl. Road Type: ❑ Arterial ❑Collector ® Local ❑Alley ❑Other:
B2.Condition of Pavement: ❑New ® Good ❑ Cracked ❑Broken
B3.Is on-street parking permitted ®Y ❑N If yes, approximate number of cars per block: 0 '
B4.Are large cul-de-sacs present? ❑ Y ®N
B5.Is trash present in curb and gutter?If so, Index Rating for Accumulation in Gutters ,
use the index to the right to record amount. Clean Filth
Sediment ❑ I ❑2 ❑ 3 [-14 ❑ 5
Organic Material ❑ 1 ❑2 [-13 ❑4 ❑ 5 t
Litter ❑ 1 ❑2 ❑ 3 ❑4 ❑ 5
C. Storm Drain Inlets and Catch Basins
Cl.Type of storm drain conveyance: ® open ❑ enclosed ❑mixed '
C2.Percentage of inlets with catch basin Stora e: 0 ❑N/A
Sample 1-2 catch basins per NSAIHSI C3.Catch basin#1 C4. Catch basin#2
Latitude _°
Longitude —c-1n —e--n '
LMK#
Picture# ,
Current Condition ❑Wet ®Dry ❑ Wet ❑Dry
Condition of Inlet ❑Clear®Obstructed ❑Clear❑Obstructed
Litter Accumulation ❑Y ®N ❑Y ❑N
Organics Accumulation ®Y ❑N ❑Y ❑N '
Sediment Accumulation ®Y ❑N ❑Y ❑ N
Sediment Depth in feet R. ft.
Water Depth fl. ft. '
Evidence of oil and grease ❑Y ®N ❑Y ❑N
Sulfur smell ❑Y ®N ❑Y ❑N
Accessible to vacuum truck ®Y ❑N ❑Y ❑N '
D.Non-Residential Parking Lot(>2 acres)
Dl.Approximate size: acres
D2.Lot Utilization: ❑ Full ❑About half full ❑ Empty ,
D3.Overall condition of Pavement: ❑ Smooth(no cracks) ❑ Medium(few cracks) ❑ Rough(many cracks)
❑ Very Rough(numerous cracks and depressions)
D4.Is lot served by a storm water treatment practice? ❑ Y ❑ N If yes,describe: '
D5.On-site retrofit otential: L Excellent ❑ Good ❑Poor
E-12
' Streets and Storm Drains SSD
' E.Municipal Pollutant Reduction Strategies
El.De ree of pollutant accumulation in the system: ❑ High ❑ Medium ❑ Low ❑ None
' E2.Rate the feasibility of the following pollution prevention strategies:
Street Sweeping: ® High ❑Moderate ❑Low
Storm Drain Stenciling: ®High ❑Moderate ❑Low
Catch Basin Clean-outs: ®High ❑ Moderate ❑ Low
Parking Lot Retrofit Potential: ❑High ❑ Moderate ❑ Low
Catch Basin Sketches
#1 #2
' Notes:
1
' E-13
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Hashamomuck Pond t
NSA H-14 '
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