HomeMy WebLinkAboutProposed Mitigation Traffic Impact Assessment GREE'NPORT MEDICAL OFFICES AND
RESIDENCES
TOWN OF SOU HOLD
SUFFOLK COUNTY NEW FORE
(SCTM 1000-34-2-1)
DRAFFIC IMPACT ASSESSMENT
NOVRECEIVED
12022
_�Board
Pl
OCTOBER 26, 2022
Lili%%A L.K. McLean Associates, P.C.
437 S. Country Road, Brookhaven, NY 11719
TABLE OF
Page
1.0 Introduction.......,..,............. ... . ....... ............ 1
2.0 Existing Traffic Conditions............................................ ........ .__ ........ ..,...... ..,.,.2
3.0 Future "No Build" Traffic Conditions................................. __........,....,...............,....,..........4
4.0 Proposed Site Trip Generation, Traffic Distribution and Trip Assignment.................. 5
5.0 Driveway Intersection Location and Capacity Analysis...........................................___6
6.0 Pedestrian and Bicyclist Considerations........... ......m. ......,. -....... .................7
7.0 Accident Analysis........................... ......... ......... .., „ ......,.. ....................,........8
8.0 Proposed Traffic Mitigation........................ ....... ........ ...........9
9.0 Recommendations.............................................................,..........................................
....... 11
A andi
2025 (Estimated Time of Completion) Traffic Volumes at the Roundabout
Site Generated Weekday AM and PM Peak Hour Volumes—Original Proposal,
Drawings VOL-01 and VOL-02
Westerly Driveway Intersection Capacity Analysis Results--Original Proposal
Site Generated Weekday AM and PM Peak Hour Volumes—Downsized Proposal,
Drawings VOL-03 and VOL-04
Westerly Driveway Intersection Capacity Analysis Results--Downsized Proposal
Driveway Intersection Sight Distance—Drawing SD-01
1.0 INTODUC'TlON
The project is located at the southeast corner of the intersection of Main Street (NY 25) and
North Road (County Road 48/NY 25) in Greenport. A Location Map (Figure 1) is shown on the
following page. The project proposes to construct four campus-style mixed use buildings on a
vacant 4.7 acre parcel in the RO Zoning District. All four buildings will consist of three units of
medical office space (4,847 SF) on the first floor, as well as ten workforce apartments on the
second floor, with the exception of only five apartments in one of the buildings (35 total
apartments).
A Site Plan (Figure 2) follows the Location Map.
Special exception approval is required by the Town Code to permit construction of apartments
above professional offices.
This Traffic Assessment focuses on potential traffic impacts of the project, using the State
Environmental Quality Review Act (SEQR) as the guideline for the determination of any required
mitigation measures for traffic impacts. The proposed reconstruction of the adjacent NY 25/CR
48 intersection by the NY State Department of Transportation (NYSDOT) has an effect on the
scope of work to determine the traffic impacts of this project, as well as the location of the site's
roadway access points. The reconstruction project will provide a roundabout at the intersection,
as well as roundabout approach roadways. In Figure 3, NYSDOT's alignment of the roundabout
and its approach roadways is superimposed on the development's Site Plan for the Revised
Proposal.
Federal and State funds have been programmed for the NYSDOT reconstruction project, and the
project's (PIN 0801.01) current schedule is as follows:
• Construction is expected to begin in Winter 2023/2024
• Construction is expected to be completed in Fall 2025 (three years from the date of this
assessment).
NYSDOT is fully aware of the development, and will be acquiring property from the developer of
the site in order to construct the project (see NYSDOT property acquisition line on Figures 2 and
3). In its May 2022 Draft of the Final Design Report for the project, NYSDOT's consultant
developed traffic volume projections for the Estimated Time of Completion (ETC) of the project.
Since the completion of the proposed development is expected to approximately coincide with
NYSDOT's construction completion, the approach utilized in this assessment is to use NYSDOT's
ETC traffic volumes as the "No Build" traffic volumes along NY 25 at the site's two access
driveways, in order to assess the traffic capacity of the driveway intersections.
GREENPORT MEDICAL OFFICES AND RESIDENCES PAGE 1
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2.0 FISTING TRAFFIC CONDITIONS
Roadway Network
As noted, NYSDOT will be reconstructing the NY 25/CR 48 intersection with a roundabout. The
intersection is currently controlled by a Stop sign facing northbound motorists on NY 25 East
who desire to turn left onto CR 48, as well as by Yield signs, one facing northbound motorists on
NY 25 East who are turning right onto NY 25 East/North Road, and another facing motorists
turning right from eastbound CR 48 onto NY 25 West, heading to downtown Greenport.
The current roadway conditions adjacent to the site are summarized below:
• County Road_48 North Road: This is the roadway west of the NY 25/CR 48 intersection.
It consists of a single lane in each direction, with paved shoulders. The posted speed
limit is 45 mph in the vicinity of the project site. The roadway is designated as NY State
Bike Route 25, but the shoulders are not marked as bike lanes.
• NY 25 Ngrth Road east of the NY 25 CR 48 intersection: NY 25 consists of a single lane
in each direction, with paved shoulders. The posted speed limit is 45 mph in the vicinity
of the project site. The roadway is designated as NY State Bike Route 25, but the
shoulders are not marked as bike lanes.
• NY 25Mvain Street south of the NY 25 CR 48 intersection: NY 25 consists of a single
lane in each direction, with paved shoulders. The posted speed limit is 30 mph in the
vicinity of the project site.
• Sound Road: Sound Road intersects the north side of NY 25, about 100 feet east of the
main NY 25/CR 48 intersection, and only about 30 feet offset from the north-to-
eastbound NY 25 right turn connecting lane. It has a 30 mph posted speed limit and
carries two-way traffic on an unmarked pavement.
The S92 Suffolk County Transit Bus Route, a heavily utilized route, runs from East Hampton on
the South Fork, through Riverhead and onto the North Fork, and along NY 25 through the NY
25/CR 48 intersection. Current service on weekdays and weekends between downtown
Greenport and Orient Point occurs at variable intervals during the peak ridership times of the
day. There are no bus stops in the vicinity of the site. The Suffolk County Department of
Planning and the Environment is currently conducting a "Reimagining Transit" Study which is
evaluating bus service on all of Suffolk Transit's routes.
Site Traffic Obsery tions
An LKMA Traffic Engineer conducted field observations on the roadways in the vicinity of the
site during mid-day Saturday September 3, 2022 (Labor Day weekend). Photos appear on the
following page. Since the Cross Sound Ferry to Connecticut is located only eight miles to the
east, "platoons" of vehicles destined to and from the ferry terminal pass through the NY 25/CR
48 intersection. Eastbound vehicles on CR 48 may be traveling well in excess of the posted
speed limit when ferry departure times are approaching, as delayed motorists attempt to make
their reserved ferry departure time. Westbound motorists who have exited the ferry approach
the CR 48/NY 25 intersection in clusters of vehicles.
GREENPORT MEDICAL OFFICES AND RESIDENCES PAGE 2
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Looking south at the NY 25/CR 48 intersection, showing the S92 Suffolk Transit bus from
Orient turning left onto westbound NY 25 toward downtown Greenport.
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Looking east at the NY 25 intersection from CR 48. Left turning motorists from
downtown Greenport have difficulties turning left onto CR 48, needing to wait for both
westbound NY 25 motorists, who are awaiting a gap in oncoming eastbound CR 48 traffic
to turn left, as well as eastbound CR 48 vehicles proceeding through the intersection.
GREENPORT MEDICAL OFFICES AND RESIDENCES PAGE 3
3.0 FUTURE'-`N0 BUILD" TRAFFIC CQMD-I IONS
As noted in the Introduction, NYSDOT's roundabout ETC traffic volumes are being utilized as the
"No Build" traffic volumes along NY 25 at the site's two access driveways, in order to assess the
traffic capacity of the proposed site driveway intersections. NYSDOT's traffic volumes include
appropriate traffic growth factors, as well as consideration of other identified private
development projects in the vicinity of the site which may result in traffic volume increases.
In NYSDOT's Design Report, extensive traffic capacity analyses were performed for the existing
dual "T" intersection configuration at NY 25/Main Street with CR 48/North Road, i.e. with the NY
25/Main Street intersection with CR 48/North Road considered the west intersection and NY
25/North Road with Sound Road considered the east intersection. The analyses note poor
Levels of Service (LOS) for vehicles turning left from northbound NY 25 onto CR 48 at the west
intersection.
The Report then indicates the pursuit of the reconstruction of the existing "T" intersection of NY
25/Main Street with CR 48/North Road into a roundabout as a measure to mitigate the poor
LOS, with the following results excerpted from the report.
SIGNALIZED INTERSECTION CAPACITY ANALYSIS SUMMARY
(EXISTING CONDITION-2017)
NYS Route 25 at CR 48!Sound Road Level of Service and Delays (sec)
ETC+20 Mitigation 1 (Routidabout)
AM P[AK MIDDAY PEAK PM PEAK
LANE GROUP
MOVEMENT Queue We ratio Delay LOS Queue vlc ratio Delay LOS Queue v1c ratio Delay LOS
(ft) (sec) (ft) (sec) (ft) (sec)
EB LTR 3 0.53 9.6 A 3 0.49 9.4 A 2 0.44 8.4 A
WB LTR 2 0.40 6.9 A 4 0.61 11.0 B 6 0 69 13.4 B
NB LTR 1 023 6.7 A 2 0.38 8 3 A 2 0.34 7.4 A
SB LTR 0 0.03 5.0 A 0 0.05 6.8 A 0 0-05 7.4 A
OVERALL 0.53 $1 A 0.61 _ 9.8 A 0.69 10.6 B
Notes:
1 The capacity analysis is conducted by SYNCHRO. version 10. which utilizes the Highway Capacity Manual.
2. For LOS definition. see Appendix C-3. Constrained traffic operations are presented in "Bold" letter font on this table
3. WB =Westbound. EB = Eastbound. NB = Northbound. SB = Southbound
4. LTR=Shared left.thru and right movement
5. "Overall v!c ratio is actually max vk ratio of an approach within the intersection. However.
delay and LOS values are based on the weighted average of all signalized intersection approaches_
6. Queue (ft) shows 95th Percentile queue length in feet.
GREENPORT MEDICAL OFFICES AND RESIDENCES PAGE 4
The table indicates that with a roundabout, and for all weekday time periods 20 years after
completion of construction, the overall Levels of Service (LOS) are A or B. The LOS is based on
both the average delay per vehicle and the Volume-to-Capacity (v/c) ratio.
When completed, the proposed development will generate a minor amount of traffic, a 6%
increase at the roundabout relative to the estimated traffic volumes there in 2025 in the AM and
PM peak hours. Since the proposed roundabout, now incorporated into DOT's construction
contract, will operate at a very good LOS, the small amount of traffic generated by the proposed
development will have a minor, if any, impact on the LOS. Therefore, with adequate available
capacity the roundabout can easily accommodate the generated traffic (more information on
Trip Generation is presented in Section 4.0).
4.0 PROPOSED SITE TRIP��d�dER47"I+c�FI T '4d�FlC�7ISTplllllTlC�fU"��t17 TRAFFIC
AS.SI NME+I" 'T
Vehicular trips to and from the developed site during the weekday morning and afternoon peak
hours were generated using the Institute of Transportation Engineers' (ITE) Trip Generation
Manual, 11th Edition. Due to the uncertainties associated with the County's potential
rescheduling of S92 Bus Route service, as contemplated in the County's current Reimagining
Transit Study, no credit for a reduction in vehicular trips was taken for anticipated trips to the
site using the bus. In reality, some workers and medical office patients will utilize the bus to the
site if bus stops are established in the vicinity of the site.
The following ITE Land Use categories were utilized:
• 720—Medical Office Building
• 220—Multifamily Housing (Low Rise)
Below are the anticipated entering and exiting vehicles, for the Original Proposal:
Time Period Entering Vehicles Exiting Vehicles
Weekday Morning Peak Hour
(7:45-8:45 AM)
Medical Offices 48 13
Apartments 8 26
TOTALS 56 39
Weekday Evening Peak Hour
(4-5 PM)
Medical Offices 23 54
Apartments 23 13
TOTALS 46 67
Given that the medical offices generate the majority of trips, and that their anticipated usage on
a Saturday would be significantly lower (ITE has data with an insufficient sample size for Medical
Office Buildings on Saturdays), a Saturday peak hour was not necessary to analyze.
Based on the local population distribution, as well as the traffic flow efficiency of the roadway
routes to the site, the following trip distribution was utilized for trips to/from the site:
GREENPORT MEDICAL OFFICES AND RESIDENCES PAGE 5
• To/from the west via CR 48-55%
• To/from the south via NY 25-35%
• To/from the east via NY 25-10%
Generated traffic was assigned to these roadways based on the distribution..
5.0 DRIVEWAY INTERSECTINLQC'Ar10N ANDC P 'ITYAN ;LYSI
The Site Plan indicates two driveways from the site to NY 25, located as follows:
• A westerly (in terms of the direction of travel on NY 25) driveway to north-south Main
Street, with its southern curb line located 19' feet from, and parallel to, the project's
southerly property line
• An easterly driveway to east-west NY 25/North Road located about 300' east of the
proposed roundabout. This driveway is located at the point where NYSDOT's property
acquisition for the roundabout terminates
The westerly driveway access is located nearly as far south as possible. Because the speeds of
eastbound through vehicles coming from CR 48 will be significantly lower in the future along the
site's north frontage when vehicles are coming out of the roundabout, the easterly driveway
location is best where shown on the Site Plan. Moving the driveway further to the east and
further from the roundabout will increase eastbound approach speeds, making it potentially less
safer for motorists to make right turns onto eastbound NY 25.
It should be noted that NYSDOT's Design Report has future traffic volumes for NY 25 at both
driveway access locations; however, those volumes were anticipated for a project ETC of 2023.
As previously noted, the project ETC will be in 2025; therefore, these volumes were increased to
the year 2025 using traffic growth factors.
Given the locations of the driveways with respect to the roundabout, and considering DOT's
proposed alignment of the approaches to the roundabout, in order to optimize safety at the
driveway intersections the following turn prohibitions were assumed in performing the driveway
intersection capacity analyses:
• At the westerly driveway, southbound left turns to enter the site would be prohibited.
These turns can be made as right turns entering the main site access (easterly
driveway). As a result, motorists entering from the west would continue through the
roundabout and instead make right turns to enter the site at the easterly driveway.
Motorists entering the site from the east would use the roundabout to safely execute
a U-turn, and then make right turns to enter the site at the easterly driveway.
• At the easterly driveway, left turns entering and exiting the site would be prohibited.
Instead, motorists who exit the site and desire to travel west on CR 48 would turn
right from the westerly driveway onto northbound Main Street, then travel around
the roundabout to access westbound CR 48. As noted above, motorists entering the
site from the east would use the roundabout to safely execute a U-turn, and then
GREENPORT MEDICAL OFFICES AND RESIDENCES PAGE 6
make right turns to enter the site. For those exiting motorists who desire to head
south on Main Street, instead of turning left from the easterly driveway and using the
roundabout to proceed southerly, they would turn left from the westerly driveway
directly onto Main Street.
Driveway intersection capacity analyses for the Revised Proposal were performed in accordance
with Synchro Version 11 Software, which is based on the 6th Edition of the Transportation
Research Board's Highway Capacity Manua(.
Given that only 10% of the site's exiting traffic at the easterly driveway would execute a right
turn, causing a negligible effect on intersection capacity, capacity analyses were not performed
there. Capacity analysis results for the proposed westerly driveway intersection with Main Street
are as follows. The LOS for unsignalized intersections is based on the average delay per vehicle
for the most critical turning movement at the intersection.
Weekday Peak Hour
Time Period Critical Movement Level of Service
Morning Westbound Left + Right Turns B
Evening Westbound Left + Right Turns B
Stop Line Sight distance measurements were taken in the field in the approximate driveway
locations, in accordance with AASHTO guidelines. Figure SD-01 with this information, as well as
photographs, is included in the Appendix. For the westerly driveway, the approximate
Intersection Sight Distance (ISD) for motorists looking to the left exiting the site is estimated at
285 feet, which corresponds to a roadway Design Speed of 25 mph, less than the 30 mph posted
speed limit. The ISD is restricted by a row of large trees in the existing Right of Way of NY 25,
between the sidewalk and curb. During construction of the driveway, actual measurements of
the sight distance should be obtained, to determine if one or more of the trees should be
removed to provide adequate ISD. There is an additional ISD restriction looking to the right
from the easterly driveway; however, with the recommended prohibition of exiting left turns
from that driveway the ISD restriction is not applicable, as' exiting motorists will only be
executing right turns.
6.0 P DfSTRIA.N AND BICYCLIST CONSIDERATIONS
The Permits Section of NYSDOT has commented that a bus stop should be provided at the site.
An eastbound bus stop along the north frontage of the site would conflict with NY Bike Route
25, which runs along the shoulders along NY 25, and continues west along CR 48 on the
shoulders there. Bus stops in both directions of NY 25 could be authorized by Suffolk County
Transit on Main Street following roundabout construction, in the 10' minimum width shoulders.
The stops would be located north of the westerly driveway. Future bus stop locations are shown
on Figure 3.
GREENPORT MEDICAL OFFICES AND RESIDENCES PAGE 7
To optimize pedestrian safety, the applicant proposes to reconstruct the existing 4' wide
sidewalk on the east side of Main Street with a 5' wide ADA-compliant sidewalk, from the north
side of the westerly driveway to the limit of NYSDOT's sidewalk construction under the
roundabout project, as shown on Figures 2 and 3.
Passengers exiting buses on the west side of Main Street can walk a short distance to utilize the
south roundabout crosswalk to cross Main Street. On the east side of Main Street, passengers
exiting buses can then use new sidewalks to enter the site, adjacent to either the westerly or
easterly driveway.
7.0 ACCIDEPVTANALW lS
The NYSDOT Project Design Report contained a three-year accident (crash) analysis of the NY
25/CR 48 intersection. Noteworthy in the accident analysis was a high percentage of rear-end
accidents occurring on the north-to-eastbound right turn connecting roadway carrying
eastbound NY 25 traffic and approaching a Yield sign. These accidents are numbered 3, 4, 5, 6,
7, 11, and 12 on the diagram on the following page. All of these accidents involved an initial
vehicle stopped at the Yield sign being rear-ended by a following vehicle.
The acute angle of the ramp connection with NY 25/North Road, coupled with the speeds of
approaching vehicles on eastbound CR 48 onto eastbound NY 25, are conditions which
contribute to the driver of the first vehicle stopping to look over his shoulder at an approaching
vehicle to see if he has an acceptable safe gap in traffic to proceed beyond the Yield sign. Given
the Yield sign, the driver may be rolling at a low speed as he looks over his shoulder at the
skewed intersection, and may actually start to turn before he realizes the gap is unacceptable
and then stops abruptly. The following driver, seeing the first vehicle moving forward, may think
the vehicle has proceeded and after he turns around and views an acceptable gap, immediately
proceeds forward without looking.
There is no need to update NYSDOT's accident analysis, because construction of the roundabout
will reduce the number of significant (injury) accidents at the NY 25/CR 48 intersection and its
approaches. This will occur because right-angle type collisions occurring at intersections with
Stop sign control (e.g. for the northbound-to-westbound left turn movement) often result in
injuries, sometimes severe, to vehicle occupants. The conflicting accidents at roundabouts
involving vehicles approaching from different directions are low speed merging accidents, most
of which do not result in injuries. The roundabout will reduce the speed of eastbound vehicles
at the eastern driveway access, because these vehicles arriving there will be traveling at lower
speeds after exiting the roundabout than the current speeds of eastbound vehicles from CR 48.
The minimal traffic volume increases associated with the proposed development will not result
in a significant increase in accidents at the roundabout.
GREENPORT MEDICAL OFFICES AND RESIDENCES PAGE 8
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Seven of the 16 accidents (44%) with available details involved rear end collisions at the
northbound-to-eastbound yield sign.
8.0 PROPOSED TRAFFIC MITI
In order to further limit the potential for traffic capacity and safety impacts, downsizing the
proposed development has been proposed by the developer. The revised proposal consists of
the deletion of one of the proposed buildings. Each of the three proposed buildings will now
accommodate three units of medical office space (4,847 SF) on the first floor as well as ten
workforce apartments on the second floor, for a total of 30 apartments.
The figures on the following pages depict the proposed project:
Figure 4—Revised Site Plan, dated October 26, 2022. With the elimination of the
westernmost proposed building under the downsized proposal, the westerly driveway to
north-south Main Street was able to be moved further north to increase its buffer from
residences along the south property line. In order to maintain the maximum distance
from the proposed roundabout, the driveway was curved, to intersect with Main Street
approximately 16' feet from the project's southerly property line in order to ensure that
the proposed south curb radius meets the existing curb just north of the south property
line.
GREENPORT MEDICAL OFFICES AND RESIDENCES PAGE 9
Figure 5—Revised Site Plan, dated October 20, 2022, showing NYSDOT's alignment of
the roundabout and its approach roadways, along with NYSDOT's property acquisition
line for the roundabout project
Downsizing the project results in decreased trip generation. The table below indicates the
proposed trips in the weekday morning and evening peak hours, and a comparison with the
number of trips generated by the Original Project Proposal.
Time Period Entering Vehicles Exiting Vehicles
Weekday Morning Peak Hour
(7:45-8:45 AM)
Medical Offices 36 9
Apartments 8 24
44 (reduced from 56) 33 (reduced from 39)
Weekday Evening Peak Hour
(4-5 PM)
Medical Offices 17 40
Apartments 21 12
38 (reduced from 46) 52 (reduced from 67)
As in the Original Proposal, due to the uncertainties associated with the County's potential
rescheduling of S92 Bus Route service, as contemplated in the County's current Reimagining
Transit Study, no credit for a reduction in vehicular trips was taken for anticipated trips to the
site using the bus. In reality, some workers and medical office patients will utilize the bus to the
site if bus stops are established in the vicinity of the site.
When completed, the downsized development will generate a minor amount of traffic, less than
a 5% increase in traffic volumes at the roundabout relative to the estimated traffic volumes there
in 2025 in the AM and PM peak hours, compared with a 6% increase in the Original Proposal.
Since the proposed roundabout will operate at a very good LOS, the amount of traffic generated
by the downsized development will have a minor, if any, and lesser impact on the LOS than the
Original Proposal. Therefore, with adequate available capacity the roundabout can very easily
accommodate the generated traffic.
As with the Original Proposal, given that only 10% of the site's exiting traffic at the easterly
driveway would execute a right turn, causing a negligible effect on intersection capacity,
capacity analyses were not performed there. The LOS for unsignalized intersections is based on
the average delay per vehicle for the most critical turning movement at the intersection. Under
the Downsized Proposal, the average delays per vehicle are reduced slightly, and the revised
very good LOS results for the proposed westerly driveway intersection are identical to those in
the Original Proposal, and are as follows:
GREENPORT MEDICAL OFFICES AND RESIDENCES PAGE 10
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Weekday Peak Hour
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9.0 RECOMMENDATIONS
Given the locations of the driveways with respect to the roundabout, and considering DOT's
proposed alignment of the approaches to the roundabout, in order to optimize safety at the
driveway intersections the following recommendations can be made:
• At the westerly driveway, southbound left turns to enter the site should be prohibited
• At the easterly driveway, left turns entering and exiting the site should be prohibited
Since the proposed roundabout, now incorporated into DOT's construction contract, will
operate at a very good LOS, the amount of traffic generated by the development will have a
minor, if any, impact on the LOS. Therefore, with adequate available capacity the roundabout
can easily accommodate the generated traffic.
Since the reduced traffic generation under the Downsized Proposal will further reduce both the
minor impact on the LOS of the roundabout, as well as average vehicle delays at the intersection
of the westerly site driveway with Main Street, it is recommended that the Downsized Proposal
be approved.
In addition, the available Intersection Sight Distance (ISD) south of the westerly driveway will
need to be measured during construction, in order to determine if one or more large trees
within the existing NY 25 Right of Way should be removed to provide adequate ISD.
GREENPORT MEDICAL OFFICES AND RESIDENCES PAGE 11
APPENDIX
2025 (Estimated Time of Completion) Traffic Volumes at the Roundabout
Site Generated Weekday AM and PM Peak Hour Volumes—Original Proposal,
Drawings VOL-01 and VOL-02
Westerly Driveway Intersection Capacity Analysis Results--Original Proposal
Site Generated Weekday AM and PM Peak Hour Volumes—Downsized Proposal
Drawings VOL-03 and VOL-04
Westerly Driveway Intersection Capacity Analysis Results--Downsized Proposal
Driveway Intersection Sight Distance—Drawing SD-01
GREENPORT MEDICAL OFFICES AND RESIDENCES PAGE 12
TRAFFIC VOLUMES--NY 25/CR 48 INTERSECTION
Source: NYSDOT Draft Final Design Report, PIN 0801.01
AM Peak Hour(7:45 to 8:45)
Movement 2023 2025
EB-T 318 321
EB-R 110 111
WB-L 115 116
WB-T 255 257
NB-L 65 66
NB-R 94 95
TOTAL 957 966
PM Peak Hour(4:00 to 5:00)
Movement 2023 2025
EB-T 254 256
EB-R 107 108
WB-L 182 184
W B-T 456 460
NB-L 124 125
NB-R 149 150
TOTAL 1272 1283
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MAIN STREET AT PROPOSED WEST ACCESS DRIVEWAY I
AM Peak Hour PM Peak Hour
Mvmnt Mvmnt Mvmnt Inter. Inter. Mvmnt Mvmnt Mvmnt Inter.
Condition Mvmnt Inter.
Delay Vic LOS Delay LOS Delay V!C LOS Delay LOS
(sedveh) Ratio (see/veh) (sedveh) Ratio (sedveh)
Build NB-TR 0.0 0.00 A 0.0 0.00 A
ETC SB-LT 0.0 0.00 A 0.8 A 0.0 0.00 A 1.1 A
(2025) WB-LR 10.3 0.05 B 11.9 0.40 B
Lanes, Volumes, Timings
13: Main Street & Driveway 1 09/14/2022
f- t
Lane Group, WBL WBR NBT NBR SBL SBT
Lane Configurations Y T+ +1
Traffic Volume(vph) 14 21 161 20 0 227
Future Volume(vph) 14 21 161 20 0 227
Ideal Flow(vphpl) 1900 1900 1900 1900 1900 1900
Lane Util, Factor 1.00 1.00 1.00 1.00 1.00 1.00
Frt 0.918 0.985
Flt Protected 0.981
Satd. Flow(prot) 1678 0 1835 0 0 1863
Flt Permitted 0.981
Satd. Flow(perm) 1678 0 1835 0 0 1863
Link Speed (mph) 30 30 30
Link Distance(ft) 196 220 348
Travel Time(s) 4.5 5.0 7.9
Peak Hour Factor 0.92 0.92 0.92 0.92 0.92 0.92
Adj. Flow(vph) 15 23 175 22 0 247
Shared Lane Traffic(%)
Lane Group Flow(vph) 38 0 197 0 0 247
Enter Blocked Intersection No No No No No No
Lane Alignment Left Right Left Right Left Left
Median Width(ft) 12 0 0
Link Offset(ft) 0 0 0
Crosswalk Width(ft) 16 16 16
Two way Left Turn Lane
Headway Factor 1.00 1.00 1.00 1,00 1.00 1.00
Turning Speed(mph) 15 9 9 15
Sign Control Stop Free Free
Intersection Summa.
Area Type: Other
Control Type: Unsignalized
Intersection Capacity Utilization 21.9% ICU Level of Service A
Analysis Period(min) 15
BUILD AM PEAK HOUR ETC(2025) Synchro 11 Report
RB Page 7
HCM 6th TWSC
13: Main Street & Driveway 1 09/14/2022
Intersection
Int Delay,s/veh 0.8
Movement—_ Vh1 L WBR, NBT NBR SBL SBT
Lane Configurations Y T 4
Traffic Vol, veh/h 14 21 161 20 0 227
Future Vol,veh/h 14 21 161 20 0 227
Conflicting Peds,#/hr 0 0 0 0 0 0
Sign Control Stop Stop Free Free Free Free
RT Channelized - None None None
Storage Length 0 - - -
Veh in Median Storage,# 0 0 0
Grade, % 0 - 0 - 0
Peak Hour Factor 92 92 92 92 92 92
Heavy Vehicles, % 2 2 2 2 2 2
Mvmt Flow 15 23 175 22 0 247
Major/Minor Minorl Ma ort Ma or2
Conflicting Flow All 433 186 0 0 197 0
Stage 1 186 - -
Stage 2 247 - -
Critical Hdwy 6.42 6.22 4,12
Critical Hdwy Stg 1 5.42 - - - -
Critical Hdwy Stg 2 5.42
Follow-up Hdwy 3.518 3.318 - - 2.218
Pot Cap-1 Maneuver 580 856 1376
Stage 1 846 -
Stage 2 794 -
Platoon blocked, % - -
Mov Cap-1 Maneuver 580 856 1376
Mov Cap-2 Maneuver 580 -
Stage 1 846
Stage 2 794 - - -
NB -
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HCM Control Delay, s 10.3 0 0
HCM LOS B
Minor Lane%Ma or,Mvmt NBT ' NBRWBLn1; SBL SBT ,
Capacity(vehlh) - 719 1376
HCM Lane V/C Ratio 0.053 - -
HCM Control Delay(s) - 10.3 0
HCM Lane LOS B A -
HCM 95th %tile Q(veh) - 0.2 0
BUILD AM PEAK HOUR ETC(2025) Synchro 11 Report
RB Page 8
Lanes, Volumes, Timings
13: Main Street & Driveway1 09114/2022
t ►
Lane Group WBL WBR NBT NBR SBL SBT
Lane Configurations Y T� +T
Traffic Volume(vph) 23 37 275 16 0 292
Future Volume(vph) 23 37 275 16 0 292
Ideal Flow(vphpl) 1900 1900 1900 1900 1900 1900
Lane Util. Factor 1.00 1.00 1.00 1.00 1.00 1.00
Frt 0.917 0.993
Flt Protected 0.981
Satd. Flow(prot) 1676 0 1850 0 0 1863
Flt Permitted 0.981
Satd. Flow(perm) 1676 0 1850 0 0 1863
Link Speed (mph) 30 30 30
Link Distance(ft) 157 220 348
Travel Time(s) 3.6 5.0 7.9
Peak Hour Factor 0.92 0.92 0.92 0.92 0.92 0.92
Adj. Flow(vph) 25 40 299 17 0 317
Shared Lane Traffic(%)
Lane Group Flow(vph) 65 0 316 0 0 317
Enter Blocked Intersection No No No No No No
Lane Alignment Left Right Left Right Left Left
Median Width(ft) 12 0 0
Link Offset(ft) 0 0 0
Crosswalk Width(ft) 16 16 16
Two way Left Turn Lane
Headway Factor 1.00 1.00 1.00 1.00 1.00 1,00
Turning Speed (mph) 15 9 9 15
Sign Control Stop Free Free
Intersection Summary
Area Type: Other
Control Type: Unsignalized
Intersection Capacity Utilization 25.7% ICU Level of Service A
Analysis Period(min) 15
BUILD PM PEAK HOUR ETC(2025) Synchro 11 Report
RB Page 7
HCM 6th TWSC
13: Main Street & Driveway 1 0911412022
Intersection
Int Delay,s/veh 1,1
Movement: WBL WBR NBT; NBR SBL SBT
Lane Configurations Y ra 4
Traffic Vol, veh/h 23 37 275 16 0 292
Future Vol,veh/h 23 37 275 16 0 292
Conflicting Peds,#/hr 0 0 0 0 0 0
Sign Control Stop Stop Free Free Free Free
RT Channelized - None None None
Storage Length 0 - - - -
Veh in Median Storage,# 0 - 0 0
Grade, % 0 - 0 - 0
Peak Hour Factor 92 92 92 92 92 92
Heavy Vehicles, % 2 2 2 2 2 2
Mvmt Flow 25 40 299 17 0 317
Ma or/Minor Minorl M 'orl Ma'or2
Conflicting Flow All 625 308 0 0 316 0
Stage 1 308
Stage 2 317 - - -
Critical Hdwy 6.42 6.22 _ 4.12
Critical Hdwy Stg 1 5.42 - -
Critical Hdwy Stg 2 5.42
Follow-up Hdwy 3.518 3.318 - 2.218
Pot Cap-1 Maneuver 449 732 1244
Stage 745
Stage 2 738
Platoon blocked, % -
Mov Cap-1 Maneuver 449 732 1244
Mov Cap-2 Maneuver 449 - - -
Stage 1 745 -
Stage 2 738 -
A r11,` .WB B SB
HCM Control Delay, s 11.9 0 0
HCM LOS B
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Mnor,Lo' olMorMvmt NBT iBRWLrt1 SBL, SBT,
Capacity(veh/h) 590 1244 -
HCM Lane V/C Ratio 0.111 -
HCM Control Delay(s) 11.9 0
HCM Lane LOS B A -
HCM 95th %tile Q(veh) 0.4 0 -
BUILD PM PEAK HOUR ETC(2025) Synchro 11 Report
RB Page 8
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SYNCHRO LEVEL OF SERVICE SUMMARY FOR 2025
MAIN STREET AT PROPOSED WEST ACCESS DRIVEWAY 1
AM Leak Hour I'M Peak flour
MvmnL Mvmnt Inter. Mvmnt MvmnL Inter.
Condition Mvmnt Mvmnt. Inter. Mvmnt Inter.
Delay v/C LOS Delay LOS Delay v/C LOS Delay LOS
(sedveh) Ratio (seelveh) (ser/veh) Ratio (sedveh)
Build NB-TR 0.0 1 0.00 A 0.0 0.00 A
ETC SB-LT 0.0 0.00 A 0.7 A 0.0 0.00 A 0.9 A
(2025) WB-LR 10.2 0.05 B 11.7 0.09 B
Lanes, Volumes, Timings
13: Main Street & Access Driveway 1 09/22/2022
,or k- t `
Lane Gr a 1. WBR NBT NIBIR SBL SBT
Lane Configurations Y 1�
Traffic Volume(vph) 12 18 161 15 0 227
Future Volume(vph) 12 18 161 15 0 227
Ideal Flow(vphpl) 1900 1900 1900 1900 1900 1900
Lane Util. Factor 1.00 1.00 1.00 1.00 1.00 1.00
Frt 0.918 0.989
Flt Protected 0.981
Said.Flow(prot) 1678 0 1842 0 0 1863
Flt Permitted 0.981
Satd.Flow(perm) 1678 0 1842 0 0 1863
Link Speed(mph) 30 30 30
Link Distance(ft) 138 220 348
Travel Time(s) 3.1 5.0 7.9
Peak Hour Factor 0.92 0.92 0.92 0.92 0.92 0.92
Adj.Flow(vph) 13 20 175 16 0 247
Shared Lane Traffic(%)
Lane Group Flow(vph) 33 0 191 0 0 247
Enter Blocked Intersection No No No No No No
Lane Alignment Left Right Left Right Left Left
Median Width(ft) 12 0 0
Link Offset(ft) 0 0 0
Crosswalk Width(ft) 16 16 16
Two way Left Turn Lane
Headway Factor 1.00 1.00 1 00 1.00 1.00 1.00
Turning Speed(mph) 15 9 9 15
Sign Control Stop Free Free
Intersection$umr 1
Area Type: Other
Control Type: Unsignalized
Intersection Capacity Utilization 21.9% ICU Level of Service A
Analysis Period (min) 15
BUILD AM PEAK HOUR ETC(2025) Synchro 11 Report
RB Page 5
HCM 6th TWSC
13: Main Street &Access Driveway 1 09/22/2022
Intersection.
Int Delay, s/veh 0.7
Mov rnent WBL WBR NBT B ' SBL : BT
Lane Configurations Y '+ t
Traffic Vol,veh/h 12 18 161 15 0 227
Future Vol, veh/h 12 18 161 15 0 227
Conflicting Peds,#/hr 0 0 0 0 0 0
Sign Control Stop Stop Free Free Free Free
RT Channelized - None - None None
Storage Length 0 -
Veh in Median Storage,# 0 0 0
Grade, % 0 - 0 - - 0
Peak Hour Factor 92 92 92 92 92 92
Heavy Vehicles, % 2 2 2 2 2 2
Mvmt Flow 13 20 175 16 0 247
Major/Minor;., Minor1 'Ma ort: Ma oQ
Conflicting Flow All 430 183 0 0 - -
Stage 1 183 -
Stage 2 247 - -
Critical Hdwy 6.42 6.22 -
Critical Hdwy Stg 1 5.42 - - - -
Critical Hdwy Stg 2 5.42
Follow-up Hdwy 3.518 3.318 -
Pot Cap-1 Maneuver 582 859 - 0
Stage 1 848 - 0 -
Stage 2 794 0
Platoon blocked, % -
Mov Cap-1 Maneuver 582 859
Mov Cap-2 Maneuver 582 - _
Stage 1 848
Stage 2 794 -
A " roac WB„ NB: ; SB
HCM Control Delay, s 10.2 0 0
HCM LOS B
Mirror Lane%Ma orMvmt , NBT,, N
BRWBLri1,
Capacity(veh/h) 722
HCM Lane V/C Ratio - - 0.045 -
HCM Control Delay(s) 10.2 _
HCM Lane LOS - - B -
HCM 95th%tile Q(veh) 0.1
BUILD AM PEAK HOUR ETC (2025) Synchro 11 Report
RB Page 6
Lanes, Volumes, Timings
13: Main Street &Access Driveway1 092212022
f- t
Laneteu ii: SSR NBT NSM ,SBL - SBT
Lane Configurations t
Traffic Volume(vph) 18 29 275 13 0 292
Future Volume(vph) 18 29 275 13 0 292
Ideal Flow(vphpl) 1900 1900 1900 1900 1900 1900
Lane Util. Factor 1.00 1.00 1.00 1.00 1.00 1.00
Frt 0.917 0.994
Flt Protected 0.981
Satd. Flow(prot) 1676 0 1852 0 0 1863
Flt Permitted 0.981
Satd. Flow(perm) 1676 0 1852 0 0 1863
Link Speed (mph) 30 30 30
Link Distance(ft) 174 220 348
Travel Time(s) 4.0 5.0 7.9
Peak Hour Factor 0.92 0.92 0.92 0.92 0.92 0.92
Adj. Flow(vph) 20 32 299 14 0 317
Shared Lane Traffic(%)
Lane Group Flow(vph) 52 0 313 0 0 317
Enter Blocked Intersection No No No No No No
Lane Alignment Left Right Left Right Left Left
Median Width(ft) 12 0 0
Link Offset(ft) 0 0 0
Crosswalk Width(ft) 16 16 16
Two way Left Turn Lane
Headway Factor 1.00 1.00 1.00 1.00 1.00 1.00
Turning Speed(mph) 15 9 9 15
Sign Control Stop Free Free
Intersection Summary
Area Type: Other
Control Type: Unsignalized
Intersection Capacity Utilization 25.4% ICU Level of Service A
Analysis Period(min) 15
BUILD PM PEAK HOUR ETC(2025) Synchro 11 Report
RB Page 5
HCM 6th TWSC
13: Main Street &Access Driveway 1 09122/2022
Intersection,.
Int Delay,slveh 0.9
Minnetat- WBL WBR NBT NBR SBL SBT
Lane Configurations t
Traffic Vol, vehlh 18 29 275 13 0 292
Future Vol, vehlh 18 29 275 13 0 292
Conflicting Peds,#1hr 0 0 0 0 0 0
Sign Control Stop Stop Free Free Free Free
RT Channelized - None None None
Storage Length 0 - ~
Veh in Median Storage,# 0 - 0 0
Grade, % 0 - 0 0
Peak Hour Factor 92 92 92 92 92 92
Heavy Vehicles, % 2 2 2 2 2 2
Mvmt Flow 20 32 299 14 0 317
Ma'orN or Minor1 Ma'or1 Ma or2
Conflicting Flow All 623 306 0 0 ~
Stage 1 306 -
Stage 2 317 -
Critical Hdwy 6.42 6.22
Critical Hdwy Stg 1 5.42
Critical Hdwy Stg 2 5.42 -
Follow-up Hdwy 3.518 3.318
Pot Cap-1 Maneuver 450 734 0
Stage 1 747 0
Stage 2 738 0
Platoon blocked, %
Mov Cap-1 Maneuver 450 734
Mov Cap-2 Maneuver 450 - -
Stage 1 747 -
Stage 2 738 - ~ -
A roach;,;,, ;WB NB; SB
HCM Control Delay,s 11.7 0 0
HCM LOS B
Mirtor,Lane�Ma orrMvmt�,; NBT NBRWBLn1 SBT
Capacity(veh/h) 591
HCM Lane V/C Ratio - - 0.086
HCM Control Delay(s) 11.7
HCM Lane LOS - - B -
HCM 95th %etile Q(veh) 0.3
BUILD PM PEAK HOUR ETC(2025) Synchro 11 Report
RB Page 6
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