Loading...
HomeMy WebLinkAboutCore Watershed Protection Area 1988 REPORT of the CORE WATERSHED PROTECTION AREA SUBCOMMITTEE by Robert Ao Villa Mark S. McDonald August 2, 1988 The definitive study of groundwater within Southold Town will not be forthcoming soon. Mindful of this and heedful of the constraints placed upon the Water Advisory Committee and this subcommittee in examing the Watershed Protection Area, a basic and straightforward evaluation of the Protection Study is required. The original Watershed Protection Study was presented to this committee on 9/28/87. A follow-up, refined version was presented on 1/12/88. This report is a continuation of these studies and draws upon them as well as other sources. Witrnin the limits of present knowledge~does the/plan: /. properly ~ the area to be protected, ~,provide water of sufficient quanity and quality, 5~ afford options and a margin of safety for future ~,address the rights of people within the area, ~and provide the controls to ensure high water quality. Does the Watershed Protection Area lhave the. se qualities? The previous studies considered future water needs and outlined an area which would satisfy those needs. The studies did not deal with the owners' rights or the controls the Area would require. This report will deal with these matters in two parts. The first part will review and update the original studies. The second part will propose regulations to control activities within the 'Watershed Protection Area. These regulations clarify owners' rights and outline the steps necessary to promote and maintain a high quality water supply. PART.ONE: Review of Previous Watershed Protection Studies generations, PLACEMENT The initial proposal to utilize the groundwater divide areas of deepest recharge is both sound and practical. in the From a water management standpoint, it is sound because control - Page 1 - of the divide provides the most impact, on a per-acre basis, on the aquifer. Cleansing the aquifer, a mid-to-long-term goal, will be achieved most quickly on the divide. No portion of the aquifer can have assured water quality unless all upgradient areas are secure. Common sense dictates control of the highest areas of groundwater. In Southold, the highest areas of the aquifer are the areas of deepest recharge, making them the best locations for wells of intermediate capacity and well fields of higher capacity. Our need for future well sites is certain and the areas of deepest recharge are clearly the best locations for these wellsites. ~4~ Utilizing the divide is practical because 'this area of the town is still relatively undeveloped. While a watershed in Southold must encompass housing and farmland (or there would be no watershed), the ideal state is woodland. After woodland, in decreasing order '" of desirability are horse farms, vineyards, conventional farms, and houses. Little or no commercial use should be present. Presently, there is little woodland within the proposed Protection Area. The majority of the property is farmland, either active or fallow. While this is not as high a quality recharge state as woodland, it is suitable and allows the possibility of future woodlands. Housing represents the least desirable of the acceptable states and should be limited as much as possible. Quanti~y and Margin of Safety Using the figures in the 1/12/88 Watershed Protection Study and substituting 4.4 square miles for the area of the protection study (Sown from the 10 square miles of the original proposal), a sustained yield of 4.4 m~d-{million gallons per day) is obtained. Assuming the area encompasses 25% of the Town's farmland (approx- imately 44% of the estimated 60% of farmland within the original area), agriculture use would be 0.93 mgd leaving 3.47 mgd of excess for use in the Town. The ultimate demand for water within Page 2 - the Town has been calculated at 4.27 mgd. This leaves a shortfall of 0.8 mgd between the watershed area's ability, to supply water . I~ ' from previous studies whose larger areas allowed a surplus rather than a deficit. Furthermore, using the equation for radius of influence from the 1/12/88 report and substituting possible alternative values,-~-/~-c for hydraulic conductivity and groundwater gradient, generates ~l-~,~, values in excess of 2000 feet. This, coupled with the shortfall)l~~ from the sustained yield-versus-demand computation, indicates ~~ the watershed Protection Area, as presently proposed, may be ~~'~~"~ somewhat too small. ~ ~vu There are mitigating factors. Careful placement, spacing, and sizing of the wells may eliminate the need for a widened Protection Area by lowering the radius of influence. Concerning the shortfalJ[, good planning requires that the Protection Area ha~ths capacity to supply the entire Town. Real life constraints make this difficult to achieve however, and compromise is essential. Fortunately, private wells will play the major role in the Town's water supply for the short-to-mid, and perhaps, long-term. Importantly, Greenport Water presently supplies 7400 people with water. This represents one-third of the present population of Southold and none of Greenport's water is drawn from the protection area. Water qua,lity is the most difficult prQblem for the bulk 3pr ~he Town. The Watershed ~rotec~lon ea has an overall water quality similar to that found in m~ch of Southold. There are areas~wi~hin the Protection Area with high water quality, but much must be done to raise the overall standard. Saltwater intrusion within the Protection Area is unlikely due to the thickness of the aquifer and the clay barrier. However, - Page 3 - improper placement, extreme well depth, or overpumping, could cause saltwater intrusion. Proper controls will promote noticeable improvements in overall quality within the midterm, and ensure that intrusion does not occur. Options The shape, size and placement of options for the future. the Protection Area provide Creating a long area along the spine of the water table allows for a multitude of alternative wellsites, proper separation of wells, and a nearly continuous zone of high quality water from western most Southold Town to Greenport Water System. Targeting specific wellsites will drive the cost of these locations upward and cause further delays if, after negotiations, the sites remain unavailable. Separation between wells will permit maximum yield from the area without intrusion of a large radius of influence. The continuous zone will assure down gradient areas of improved quality and tend to isolate any areas of future contamination. Conclusions to Part One After reviewing the studies on a section by section basis (quality, quanity .... ), the following conclusions have been reached. Placement: No other area would offer any significant improvement over the presently proposed location. Quantity and.Margin of Safety: The proposed area is too small ~to ensure a reserve c~pa~le of suppling the entire town, without other mana§emen~_tools. Quality: Proper controls within the area can significantly improve and ensure-high quality water for the town's future. Options: The creation of a Watershed Protection Area.will allow future generations a secure and flexible water supply. - Page 4 Recommendation This subcommittee recommends that the Water Advisory Committee accept the proposed outline of the Watershed Protection Area as outlined in the Watershed Protection Study submitted on 1/12/88 with provisions for minor variations in the final map to make the plan workable. PART II Regulation and Controls Creating a Watershed Protection Area without taking measures to ensure the quality of water within the Atea would be a hollow action. Unrestricted use of the Area would do no more, at best, than maintain a state which has produced the present, unacceptable, water quality. Clearly there must be regulations to promote and maintain a high quality water supply. The discussion of regulation within the Protection Area has been occuring for more than a year. However, until this report, there has been no written submission to any Town agency regarding regulations which must be enacted with the Protection Area. Part II of this report will be such a submission. Ownership The best way to control land use is to own the property and therefore, be able to manage it for its best intended use. We all know that funds are limited, although there are some funds now avail- able (open space bond issue) and others that may soon become available.~ such as the 2% Land Transfer Tax, and the ¼% sales tax fund. Also to be considered, is the 60 million dollar fund established by Suffolk Cour~t~to purchase critically environmentally sensitive lands. This committee, our Town Board, and concerned citizens, should band together to become a forceful voice in representing Southold'~ needs for funding to purchase as much of the Core Watershed Protection Area as possible. Ownership of some of these lands can also be achieved by other means such as the use of clustering, dedications by developers, - Page 5 donations, etc. Ail known methods should be employed and the Town Board must be convinced that the ownership of all of the land within the Core Watershed Area would be to the best interest of all the people of the Town, although this goal will never be a reality within our lifetime, and perhaps, never will be. Clustering Mandatory clustering is now possible within the town as this statute is already a part of the powers given to the Town Planning Board. Many of the parcels within the core area are long, bowling alley parcels which are bisected by the boundaries of the protection area. These parcels must be managed by clustering the development outside of the watershed area and leaving the open space created as part of the protected area. With proper procedures, these lands could be deeded to the town with covenants and restrictions that they always remain open but could be used for water supply purposes. This committee should recommend that a legally sound program be developed to ensure that these lands be deeded to the Town, without compensation, for inclusion in the Core Watershed Protection Area. A second recommendation would be to grant the Planning Board discretion on the lot sizes in clustered subdivisions. At present, lot sizes can only be reduced from two acres to one acre, making it difficult to achieve the ultimate protection of environmentally sensitive lands. Developer~ are receptive to clustering as development costs are reduced, therefore, this proposal should not be a source of controversy. Transfer of Development Ri~h~ Protection of all the lands within the Core Watershed Area can not be addressed by outright purchase or the use of clustering since there are entire parcels that exist solely within the designated area. These parcels must be addressed in another - Page 6 fashion, therefore, the committee reviewed the original concept of an overlay district. As originally proposed, the overlay distict would establish a limit on housing development within the area to one dwelling for every ten acres. Since housing is the least desirable use for property within the area this proposal still merits our support. Housing is least desirable because, once the land is divided and built upon, it is usually gone forever as open space, woodland, or agricultural use. This committee, therefore, recommends the creation of a ten acre overlay district, boundaries of which are to coincide with the boundaries of the Core Watershed Protection Area. These boundaries are subject to some modification since existing parcel boundaries shall be considered in some cases, in the final establishment of the Core area. The creation of the overlay district should not be considered to be an upzoning to ten acre lots. While it is proposed to limit actual construction to one residential dwelling unit for every ten acres, the land owner would be credited with a develop- ment right for every two acres of property in his possesion. For example, if a person owned 20 acres, he could build two houses on the tract and would still have eight development rights he could sell or transfer to another parcel in an area predesignated as a receiving zone. To protect the owner's value and to make the proposal more attractive, it is proposed to compute the develop- ment rights based on total land area with nothing deducted for roadways, park areas, or sumps, as is usually required when computing the yield for a clustered subdivision. This will not only benefit the landowner in an increased yield of development rights, but will.eliminate costly time delays for the preparation of surveys and yield maps. It will al'so-enable the landowner to immediately know what his property will ~ield in the way of development A more detailed study of the area must be done to establish the exact number of such rights which would be created by this proposal and to establish a large enough receiving area to accomodate - Page 7 an orderly transfer of these rights. An earlier sug§estion to utilize zoning areas proposed as R-80 in the Master Plan Update is a valid one. Density in these R-80 zones designated as receiving zones should be restricted to that equivalent to an R-40 zone with the Planning Board again given discretion on the actual lot sizes to encourage clustering or possibly some opportunity for affordable housing. Purchase and Dedication One other proposal this committee feels should be explored and implemented concerns the proliferation of small, marginally accept- able water supplies now being developed in insular areas of the town. These small, self-contained water supplies are being developed in areas of very limited water resources where the water quality has, in most cases, already been impacted. These supplies are costly to construct and will be costly to operate. The creation of these small water systems is planning at its worst and is sure to ultimately result in another situation similar to that of the Captain Kidd Water System. To halt this kind of unplanned, hodgepodge, proliferation of small water supplies, which are very costly and not a wise expenditure of money, it is proposed to restrict the locations of any future source of water supply to sites within the Core Waatershed Area. This would lead to the creation of a town water supply system that could be properly designed and managed. At the same time, the funds expended by a developer would be for a system that can be intergrated into the overall town system that must ultimately be provided. In essence, land developers would be paying for part of a townwide system and helping to solve a problem instead of creating another one." A program should be developed whereby any sites and water supply systems created within the Core Watershed Area by a developer would be dedicated to the town at no cost. This then is the fourth method of acquiring lands within the area. - Page 8 Donation A public relations effort should be made once the Core Watershed Area is established to encourage donation of lands within the area for water supply purposes or for open spaces. Organizations, such as The Nature Conservancy, Peconic Land Trust, etc., should be approached for their assistance if having lands donated for preservation. We should look at ways that such lands could be designated with a family name of the donor to honor that person. Fuels One of the greatest threats to the groundwater is petrochemicals. The presence of even small amounts of these substances can render water unusable. Since the Protection Area is the Town's ultimate groundwater reserve it becomes imperative that we eliminate the possibility of such spills. To achieve this goal, we recommend that all future storage of such chemicals be above ground. Woodland Woodland is the best state for land within the Protection Area. Little of such land presently exists and what does exist should be preserved. Any building or further clearing of the Protection Area should be evaluated in such a way as to protect the present woodland. Other municipalities have codes governing the manage- ment of trees. Such codes should be examined and adapted to our needs. Pesticides and Fertilizers Farming wil~ continue within the Watershed Area into the future, perhaps indefinitely. Whet~h~{ farming takes its traditional form or some less conventional but-viable form, it will remain an integral part of the Watershed Protection Area. Pesticides and fertilizers are both essential to commercially profitable farming and will continue to be used once a Protection Area is established. However, such chemicals, particularly in - Page 9 bulk, represent a potential threat to groundwater quality. Mis- handling or'poor storage practices could result in an accident which would damage the water quality. Consequently, we propose that there be no bulk storage of pesticides or fertilzers within the Watershed Protection Area. Topsoil The chemistry of groundwater is impacted by many factors, one of which is the nature of the soils through which it percolates. The chemistry of topsoil provides an important purification and buffering role in the protection of groundwater quality. To remove the topsoil layer would lesson the systems ability to purify and filter contaminates on their way to tho aquifer. To ensure the topsoil layer is conserved within the are~ we recommend no topsoil be mined from any site within the area. Some permitted uses, such as greenhouses, do need to strip the topsoil from the areas beneath their buildings. While we do not oppose this practice, we must insist such soils not be removed from the property. Soils should be stored on the property, to ensure proper cover is available for restoration of the property when and if the buildings are removed. Also, no areas, other than those essential, should bo stripped of soil. Page 10