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Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
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1
THE PROBLEM

Nine million people in New York City and nearby areas enjoy access to abundant, clean, and inexpensive drinking water from that city's expansive and internationally admired water supply system. The Croton River system east of the Hudson River, originally constructed in the 1840s, drains 300 square miles and today provides about 10 percent to 12 percent of New York City's water. The other 90 percent is drawn from sources west of the Hudson River in the Catskill Mountains and the headwaters of the Delaware River. Water from this Catskill/Delaware system is collected from nearly 1,600 square miles of watershed land. Altogether, the New York City system provides an average 1.3 billion gallons of drinking water per day (Hazen and Sawyer, 1997).

New York City's drinking water is not filtered.1 Like Boston, Portland, Oregon, San Francisco, and a few other cities, New York City has relied on the natural purity of its hinterland sources, along with chlorine disinfection, to provide high-quality water without filtration. During the 1990s, that modus operandi has been challenged by national public health concerns about disinfection byproducts and microbial pathogens, among other threats. Federal regulations pursuant to the Safe Drinking Water Act2 (SDWA) now mandate filtration for public surface water supplies. However, this requirement may be waived by the U.S. Environmental Protection Agency (EPA) and state health agencies if a water supplier demonstrates it will "maintain a watershed control program, which minimizes the potential for contamination by Giardia cysts and viruses in the source

1  

 The Croton System of the New York City water supply is under order from the EPA to be filtered.

2  

 Safe Drinking Water Act, P.L. 93-523, as amended. 42 USCA, Secs. 300f et seq.

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
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water" (40 CFR 141.71 (b)(2)). Although EPA advocates watershed management at many levels and for a variety of activities (EPA, 1996), avoidance of filtration under the SDWA is the only example of a regulation that requires watershed management.

Like a handful of other cities with unfiltered water supply systems, New York City has spent considerable energy developing a watershed management program that would allow the Catskill/Delaware supply to remain unfiltered. After years of negotiation, a Memorandum of Agreement (MOA) was signed on January 21, 1997, between the City, communities in the Catskill/Delaware watershed, EPA, New York State, and certain environmental organizations. The MOA launched a massive program of watershed management and collateral payments to watershed interests in exchange for an EPA waiver from filtration effective until April 2002. Under the MOA, the City is implementing watershed management on a scale unprecedented in the United States.

Drinking water supply and other water resource issues have long relied upon the watershed as a basic management unit, and much of the science needed to support watershed-based management exists (NRC, 1999). However, because watershed boundaries rarely coincide with regional or political boundaries, the implementation of watershed management requires much more than scientific and technological progress to be effective. Social, economic, and political considerations that stem from a broad range of stakeholders with disparate interests are a necessary part of watershed management. EPA recognized this fact when it defined watershed management as "a holistic, integrated problem-solving strategy used to restore and maintain the physical, chemical, and biological integrity of aquatic ecosystems, protect human health, and provide sustainable economic growth" (EPA, 1993). As stated by the NRC (1999), "Watershed management is both institutionally and scientifically complex, and thus inherently difficult to implement."

New York City's watershed management strategy fits this characterization of the watershed approach to resource management. The MOA represents a new and complex combination of programs, policies, and management practices that was developed with input from a large number of diverse interest groups. Scientific, technological, social, and economic issues are dealt with throughout the MOA, encompassed by the overarching goal of maintaining the purity of the drinking water supply in the absence of filtration.

This report evaluates the scientific underpinnings of New York City's watershed management strategy and presents conclusions and recommendations that will contribute to its successful implementation. Because of the increasingly important role of watershed management in providing safe drinking water, many of the report's conclusions and recommendations extend beyond New York City and apply generally to surface water supplies elsewhere.

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
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EVOLUTION OF THE NEW YORK CITY WATERSHED MEMORANDUM OF AGREEMENT

In 1986, Congress amended the SDWA, tightening drinking water standards and generating new provisions for drinking water supplies. To implement this legislation, in 1989 EPA issued the Surface Water Treatment Rule (SWTR), requiring filtration for communities relying on surface water sources. This rule had tremendous fiscal implications for New York City. New York City estimated construction costs for Catskill/Delaware filtration facilities to be as much as $6 billion with annual operating expenses estimated to be more than $300 million (NYC DEP, 1993a; Paden and Shen, 1995). Although an EPA-appointed expert panel disputed the City's cost estimates (Okun et al., 1993), arguing that filtration of the Catskill/Delaware water supply could be achieved for as little as half the City's estimate, the cost of filtration was nevertheless perceived to be excessive.

Quest for Filtration Avoidance

The SWTR provides that under certain conditions, public water supplies may obtain a waiver from filtration. These conditions include creating a watershed management program, meeting standards for turbidity and fecal and total coliforms, providing adequate disinfection, and avoiding any waterborne disease outbreak. Eager to take advantage of this provision, in 1991 New York City began to develop a watershed management program that would maintain the high quality of its drinking water supply. As the agency primarily responsible for delivering safe drinking water, the New York City Department of Environmental Protection (NYC DEP) began drafting a watershed management program that would satisfy the SWTR and allow the city to avoid filtering the Catskill/Delaware supply. Water from the Croton watershed was not thought to be of sufficient quality for that system to qualify for a waiver from filtration as well. The City is currently under an order from EPA to construct a $687 million filtration plant for the Croton portion of the system.

New Watershed Rules and Regulations

The first step in filtration avoidance for the Catskill/Delaware system was improvement of the New York City Watershed Rules and Regulations dating from 1953. In 1990, NYC DEP produced a first draft of revised Rules and Regulations that, among other things, called for maintenance of buffer zones around watercourses and reservoirs and restrictions on siting and construction of sewerage facilities (NYC DEP, 1990). The proposed regulatory changes would have restricted a variety of developments, including the construction of roads, parking lots, and storage facilities for hazardous substances and waste. In addition to the Rules and Regulations, New York City proposed to acquire watershed

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

FIGURE 1-1 Land ownership in the Catskill/Delaware watershed.

land. New York City owns only about 6 percent of the Catskill/Delaware watershed, with another 20 percent being part of the New York State Catskill Forest Preserve (Figure 1-1). The other three-quarters of the watershed remain in private ownership and thus may yield contaminants from agriculture and other land use activities. Under the most extreme scenario, the City proposed to protect all developable land in the entire watershed by direct acquisition or conservation easements (NYC DEP, 1993b, p. 246). This scenario was estimated to require $2.7 billion to purchase fee title or easements on about 240,000 acres of vacant land (NYC DEP, 1993a; Pfeffer and Wagenet, 1999).

New York City's proposed actions aroused strong opposition from watershed residents who feared economic development would be stifled, property values would drop, and the local tax base would be eroded (Finnegan, 1997; Schneeweiss, 1997). The Coalition of Watershed Towns (CWT) was organized in 1991 to serve as a voice for 30 watershed towns west of the Hudson River. The CWT demanded the City compensate watershed communities for direct and indirect costs of its watershed protection program. The main goals of the CWT were to ensure the proposed regulations would not prevent reasonable community development and to limit the regulations to the minimum needed to protect water quality (Stave, 1998). The CWT pursued legal action as one means of meeting its objectives and took a lead role in opposing the proposed regulations (Finnegan, 1997).

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×
Filtration Avoidance Threatened

The long-simmering animosity between New York City and watershed communities came to a head in late 1993 when the City (1) filed a state application for a water supply permit including plans to acquire 10,000 acres in the watershed and (2) submitted a long-term watershed protection and filtration avoidance program for the Catskill/Delaware System to EPA. Uncertainty over New York City's intent to use eminent domain to gain control of the land, and the perception that the City was shifting the costs of watershed protection to upstate communities, resulted in the weakening of relations between New York City and upstate communities. This culminated in the CWT and others filing suit to prevent the City from implementing its filtration avoidance plans. The CWT cited economic burdens on watershed residents resulting from restrictions placed on the use of privately owned land, and it claimed New York City would benefit almost exclusively from the regulations. The lawsuits led to an impasse in efforts to reach a compromise about a watershed management plan (Finnegan, 1997; Pfeffer and Wagenet, 1999).

In the face of this stalemate, EPA and others urged New York governor George E. Pataki to intervene by bringing the interested parties to the negotiating table. The initial April 1995 meeting included representatives from New York City, EPA, the CWT, Putnam and Westchester counties, and others. After 18 months of negotiations, the process yielded the New York City Watershed MOA, a mammoth document comprising nearly 1,000 pages of text and attachments. This unprecedented agreement, the legal equivalent of the Hoover Dam, was signed on January 21, 1997, by New York City, New York State, EPA, the CWT, environmental organizations (the Catskill Center for Conservation and Development, the Hudson Riverkeeper, the Trust for Public Land, the Open Space Institute, and the New York Public Interest Group), and some 70 upstate towns and villages. The agreement serves as a blueprint for the City's watershed management strategy for the Catskill/Delaware supply and will cost approximately $1.5 billion over ten years. At the same time, EPA granted New York City an interim filtration avoidance determination (FAD) for the Catskill/Delaware supply until April 2002.

Memorandum of Agreement

The MOA is a landmark agreement in watershed management that recognizes both the importance of preserving high-quality drinking water and the economic health and vitality of communities located within the watersheds. The MOA explicitly states that these goals are compatible and can be met through cooperation and partnership between New York City and the upstate watershed communities. For example, in the spirit of partnership and cooperation, New York City will not acquire land through eminent domain. Instead it will seek to

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

gain fee simple title3 or conservation easements to water quality sensitive lands through a willing buyer/willing seller process. Upstate towns affirmed their new relationship with New York City by dropping outstanding lawsuits brought by the CWT. Further, all parties to the MOA agreed not to file legal challenges to block any element of the agreement. Key provisions of the MOA are shown in Box 1-1; more detail is provided in Appendix A. The filtration avoidance determination, which was incorporated in its entirety into the MOA, is summarized briefly in Box 1-2.

Watershed Agricultural Program

One important group of stakeholders that was not directly involved in the MOA negotiations was the farming community in the Catskill/Delaware watershed. The proposed Rules and Regulations raised a great deal of concern among watershed farmers, particularly because of potential land use restrictions in the form of setback distances. Farmers estimated that as much as 25 percent of their tillable land would be taken out of production if agriculture was regulated under the MOA (Coombe, 1998). Having observed the transition from agriculture to residential development in the Croton watershed and subsequent declines in water quality, NYC DEP labeled agriculture a preferred land use in the Catskill/Delaware watershed (DelVecchio, 1997). Because agriculture is also a possible source of pollutants, NYC DEP and EPA made arrangements with the farming community to establish a Watershed Agricultural Program in lieu of including agriculture as a regulated activity under the MOA.

The $35.2 million Watershed Agricultural Program was established in 1994 to engage the voluntary participation of farmers and to develop Whole Farm Plans for participating farms. Whole Farm Plans are intended to reduce pollutant loadings by using innovative best management practices (BMPs). Efforts are coordinated via the Watershed Agricultural Council, which has representation from the farming community, NYC DEP, EPA, and state agencies. The program is being implemented in two phases. Phase I established Whole Farm Plans on ten demonstration farms, while Phase II extends to all interested farms within the Catskill/Delaware watershed. As a condition of its continued waiver from filtration, EPA insisted that milestones for the Watershed Agricultural Program be included in the City's filtration avoidance determination.

3  

Fee simple absolute is the totality of legal rights in a parcel of real property, including structures and improvements, vegetation, resources below the surface and the air space above it, subject to limitations imposed by federal, state, or local laws.

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

BOX 1-1
Key Provisions of the New York City Watershed Memorandum of Agreement

Land Acquisition Program

This voluntary program allows New York City to acquire fee title or conservation easements to vacant water quality sensitive watershed lands on a ''willing buyer/willing seller" basis. All titles and conservation easements are held in perpetuity. The City has committed more than $250 million for land acquisition. Areas closer to reservoir intakes and lower in the watershed are given higher priority for acquisition.

Watershed Rules and Regulations

The Watershed Rules and Regulations control a wide variety of pollution sources such as wastewater treatment plants, on-site sewage treatment and disposal systems (septic systems), stormwater runoff, and storage of hazardous materials. The regulations contain minimum treatment requirements for some technologies that control these sources of pollution and specify effluent standards that some of these treatment technologies must meet. In addition, the regulations restrict a variety of activities from occurring in close proximity to watercourses, reservoirs, reservoir stems, controlled lakes, and wetlands. The siting of wastewater treatment plants, septic systems, and storage facilities for hazardous materials, petroleum, and salt and the construction of impervious surfaces are all restricted within "setback" distances from the major waterbodies. Detailed descriptions of the regulations are provided in Appendix A.

Watershed Protection and Partnership Programs

These programs are intended to preserve the economic and social character of watershed communities while maintaining and enhancing water quality. The Catskill Watershed Corporation (CWC), a not-for-profit corporation, was formed to manage these programs for the Catskill/Delaware watershed region. The MOA calls for about $240 million to be allocated for these efforts, which include infrastructure improvements, development, conservation, and education. The MOA also provides funds for Westchester and Putnam Counties to develop a Croton Plan. The objective of this plan is to develop a comprehensive approach to identify significant sources of pollution, to recommend measures for improving water quality, and to protect the character of watershed communities east of the Hudson River. The MOA sets aside approximately $68 million for implementation of projects developed pursuant to the Croton Plans.

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

BOX 1-2
The New York City Filtration Avoidance Determination

The current filtration avoidance determination for New York City is one of several determinations that EPA has made for the City's Catskill/Delaware water supply during the 1990s. Each new determination builds upon the tasks and accomplishments of the previous agreement. The City's current FAD expires in April 2002, at which time EPA and NYS Department of Health will determine whether NYC DEP has complied with all elements of the FAD and whether another determination will be issued.

The FAD lays out hundreds of specific tasks, or deliverables, that NYC DEP must accomplish (EPA, 1997a). Many of these tasks correspond to activities mandated by the Watershed Rules and Regulations, such as upgrading the existing wastewater treatment plants. The general task categories are listed below:

  • Compliance with objective criteria of the SWTR

  • Design of a filtration facility for the Catskill/Delaware system

  • Land acquisition

  • Data gathering and Geographic Information System (GIS) development

  • Multi-tiered water quality modeling

  • Maintenance of the Watershed Agricultural Program

  • Kensico Reservoir modeling and remediation efforts

  • Nonpoint source pollution control

  • Whole community planning

  • Repair, replacement, and upgrade of septic systems

  • Upgrade of wastewater treatment plants

  • Non-typical activities

  • Activities reports

  • Distribution system activities

  • Active disease surveillance

  • Administration

KEY ISSUES IN NEW YORK CITY AND OTHER WATER SUPPLIES

The central focus of this study is an evaluation of New York City's strategy for maintaining its high-quality drinking water through active management of its water supply watersheds. As described below, the scope of the study is broad, the issues can be addressed at several levels, and the answers involve both science and value judgments. Although the committee was asked to address several

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

specific scientific and technical issues regarding the MOA, these issues must be considered within the changing land use patterns and economic growth of the watershed region. The committee's findings and recommendations should enable the City, the State, and the watershed communities to make changes in the way management practices are being implemented in order to increase their effectiveness.

During the course of the study, the committee identified three particularly noteworthy issues that will shape the future of watershed management in water supplies across the country, both filtered and unfiltered: (1) priority setting in watershed management, (2) watershed management and economic development, and (3) filtration and other treatment options. The report revisits these issues in Chapter 12 and provides suggestions for their resolution in New York City. However, the applicability of these recommendations goes beyond New York City to other major metropolitan surface water supplies, including those that are currently unfiltered (e.g., Boston, Massachusetts; part of San Francisco, California; Seattle, Washington; Portland, Oregon; Portland, Maine; and Greenville, South Carolina).

Setting Priorities in a Watershed Management Strategy

Like most human activities, the consumption of drinking water involves certain inherent risks. Pathogenic microorganisms and chemicals that adversely affect human health are sometimes found in drinking water and pose a risk that is directly related to their concentration. In addition, poor water quality in drinking water reservoirs can pose a direct risk to the health of fish and other ecological receptors. In light of current scientific understanding of the relationships between water quality and human and ecological health, a central question for unfiltered supplies is whether a strategy based on watershed management without filtration can achieve a water supply with an acceptable level of risk to public health and the environment.

For this reason, it is often an overarching (though sometimes unstated) goal of watershed management to achieve the greatest overall risk reduction through allocation of resources among various watershed management components. In order for this to be achieved, prioritization must take place on multiple levels within a watershed management strategy. First, watershed management must be directed at the most polluting activities within a watershed. Currently, there are limited tools available for assessing the relative impacts of different sources of pollution and for mitigating their impacts. Confronted with this reality, water resource managers must be cautious when weighing the importance of different land uses and activities on overall reservoir water quality.

In addition to targeting the most polluting activities, watershed management must also consider the relative impact of various pollutants. Like many other eastern water supplies, New York City is focusing heavily on phosphorus as the

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

pollutant of concern because of its role in eutrophication and the resultant formation of disinfection byproducts. This focus may direct resources away from potentially more significant pollutants, such as microbial pathogens. In addition, future regulations may direct more attention to other pollutants.

The difficulties inherent in guarding against multiple drinking water pollutants have long been recognized by EPA and were a primary motivation for amending the SDWA. In the future, water supplies will be expected to protect against microbial pathogens, toxic organic and inorganic compounds, and disinfection byproducts in the face of increasingly strict standards for each. This challenge is especially acute for water supplies that rely on chlorine disinfection as their sole treatment process. Chapter 12 discusses the issue of prioritization during watershed management and provides suggested new program directions for New York City that may further decrease overall risk.

Watershed Management in Relation to Economic Development

Watershed management will affect, for better or worse, the future economic growth in the region. This was recognized during the MOA negotiations, with the result that numerous programs were created to help maintain the watershed economy. The strategy taken by the MOA of compensating watershed residents for the imposition of watershed regulations by investing in their economy poses several significant questions. Will this type of monetary investment in the watershed region lead to development that adversely affects water quality? Can such a strategy reduce the impact of future population growth on water quality? Should this type of investment be used in regions with high population growth rates? These questions are difficult to answer unless the contribution of different land uses to overall pollution can be quantified. Nevertheless, the report describes how these issues could affect future watershed management in New York City and other communities considering similar strategies.

Filtration, Other Treatment Options, and Watershed Management

EPA views filtration and watershed management as two forms of "treatment" that are mutually supportive. In fact, EPA strongly supports a multiple-barrier approach in which filtration, watershed management, and other treatment processes are used to arrive at the cleanest possible drinking water (EPA, 1997b). However, most interested stakeholders in New York City perceive a distinct tradeoff between filtration and watershed management, primarily due to budgetary constraints (Cronin and Kennedy, 1997, p. 208; Goldstein, 1997; Marx and Goldstein, 1999). There is concern in New York City and other places that the adoption of a strategy that incorporates both filtration and watershed management would inevitably lead to a loss of public commitment to the high level of environmental conservation reflected in the present strategy of watershed man-

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

agement and chlorine disinfection (Goldstein, 1997; Howe, 1999). This perceived conflict, and its implications for future watershed management in New York City and other unfiltered supplies, is revisited in Chapter 12. Boxes 1-3, 1-4, and 1-5 describe how this conflict has developed in three other unfiltered water supplies: Boston, Seattle, and Greenville, South Carolina.

NATIONAL RESEARCH COUNCIL STUDY

The January 1997 MOA included several changes that were introduced by the New York City Office of the Comptroller. The Comptroller was not a party to the negotiation process that produced the MOA, but his signature of approval was necessary for the agreement to be finalized, partly because of the many lawsuits that were being terminated as a result of the MOA. The Comptroller objected to a number of provisions in the public draft released in late 1996, including (1) no apparent limit of the number of new wastewater treatment plants (WWTPs) in the watersheds, (2) the transfer of primacy from EPA to the New York State Department of Health within five years, and (3) the transfer of millions of dollars to upstate communities with "inadequate" oversight that might be used to further pollute the watershed (New York City Office of the Comptroller, 1997).

Although not all of the Comptroller's objections were alleviated in the second draft of the MOA, several suggested changes were made. EPA agreed to retain primacy for ten years rather than five, and greater oversight was provided for spending of funds in the upstate communities. The Comptroller requested funding for an independent scientific review of the MOA, resulting in this National Research Council (NRC) study. The completion of the study was planned to coincide with a midterm EPA review of the MOA, also a condition imposed by the Comptroller.

Study Statement of Task and Report Organization

The MOA is the focal point of this NRC study. Various management practices, programs, and policies embodied in the MOA were reviewed in response to specific requests from the study sponsor, including prescribed setback distances, the pilot phosphorus offset program, and antidegradation policy. During its two-year tenure, the committee identified other aspects of the watershed management strategy that also warranted consideration, and it has included these in the report for consistency and completeness. The committee's work plan addressed issues in the following areas:

  • Evolving Safe Drinking Water Act

  • Enhanced monitoring program and Geographic Information System (GIS)

  • Public health protection

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

BOX 1-3
Boston Water Supply

Metropolitan Boston consists of over 100 cities and towns with a population of about 3.2 million in 1990. Situated on a deepwater harbor and surrounded by brackish estuaries, Boston has historically turned to inland sources for fresh water. Starting in the 1840s, following the model of New York City, Boston developed a series of reservoirs and aqueducts to draw water from its hinterlands. The main reservoirs in the regional water supply include the Wachusett Reservoir, 40 miles west of Boston, and Quabbin Reservoir, 70 miles west of the city. Today, Quabbin water flows to Wachusett through a 30-mile tunnel, and then into the metropolitan distribution system. One of the world's largest water supply reservoirs, Quabbin now provides about three-quarters of the Boston metropolitan water supply (Platt and Morrill, 1997). The system is jointly managed by the Metropolitan District Commission (MDC) and the Massachusetts Water Resources Authority (MWRA).

Like New York City, the metropolitan Boston system has long provided high-quality water without filtration. In both systems, land use change in privately owned portions of source watersheds threatens to reduce water purity in the future. Quabbin, whose watershed is nearly 80 percent in public ownership, has received a filtration avoidance determination (FAD) from EPA. But all Quabbin water must pass through Wachusett Reservoir, whose watershed is still predominantly (75 percent) in private ownership and which lies on the edge of the developing urban fringe of Worcester, MA. EPA has not awarded a FAD for Wachusett and has sued the MWRA and the state (in March 1998) to require a filtration plant to be constructed downstream of Wachusett. However, under a 1992 consent agreement with the state, with which EPA previously concurred, MWRA is pursuing watershed management for Wachusett while simultaneously designing the filtration plant (the dual-track approach also used by New York City). MWRA hopes to demonstrate that its watershed management program will meet EPA's requirements and justify a FAD for the Wachusett Reservoir (MDC/MWRA, 1991). A final decision is set for October 1999. Meanwhile, the MWRA is committed to installing ozonation in place of total reliance on chlorination. No Cryptosporidium oocysts have been detected in the Boston water supply (Eileen Simonson, WSCAC, personal communication, July 1, 1999).

Key elements of the Watershed Protection Plan for Wachusett include (1) septic system upgrades, (2) sewage treatment expansion,

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

(3) nonpoint source pollution control, (4) land acquisition, (5) replacement of underground storage tanks, and (6) bird harassment to reduce fecal coliform levels. In 1992, the state legislature adopted the Watershed Protection Act (Mass. General Law 1992, Ch.36), which mandates setbacks for new development along reservoirs and their tributaries (Hutchinson, 1993). In addition, since 1988, MWRA has succeeded in reducing per capita water demand by at least 16 percent through leak detection and repair, free retrofit of domestic plumbing devices, higher water rates, and public education. The MWRA demand management experience has been cited by Worldwatch Institute as an internationally significant success in sustainable water resource management (Postel, 1992).

BOX 1-4
Seattle Water Supply

Seattle has two surface water supplies: the Tolt Reservoir (one-third of the supply) and the Cedar Reservoir (two-thirds of the supply). All of the Cedar watershed is owned by the city and is undeveloped. The Tolt watershed is 75 percent city-owned, with the rest being owned by the USDA Forest Service. In both watersheds some logging has occurred, but it has recently ceased in the Tolt watershed. The combined systems serve 1.3 million customers.

Seattle received waivers from filtration for both water supplies in 1990, which are still in effect. The city has violated the Surface Water Treatment Rule once in the Cedar watershed. In 1992, fecal coliform standards were exceeded, which led to an automatic requirement for filtration. Seattle argued that this requirement is too strict because fecal coliforms are not themselves pathogenic, but are only indicators. EPA agreed that ozonation could be substituted for filtration. As a result, the Cedar watershed is having an ozonation plant built, and the Tolt is having both a filtration and an ozonation plant built. The projected costs for design and construction are $70 million.

Seattle has been preparing for filtration of the Tolt since 1989 for three main reasons:

  1. Changing regulations meant that the city would probably not be able to meet the proposed disinfection byproducts standards. The source

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×
  1. water is high in dissolved organic carbon from lignin and tannin, and Seattle did not think it would be able to comply with the proposed haloacetic acid standard.

  2. Seattle wanted the system to be reliable, even in the event that a water quality fluctuation upstream in the reservoir should occur. In particular, the Tolt system is susceptible to high levels of turbidity. Although turbidity in the main Tolt reservoir typically ranges from about 0.5 to 4.0 NTU, spot tests have found concentrations as high as 15 NTU during such conditions as low reservoir water levels, high winds, or heavy rains. During these times, the supply must be taken out of service.

  3. The utility wanted to be able to draw the Tolt Reservoir down to obtain an additional increment of supply (approximately 9 mgd). Currently, the Tolt supply experiences fluctuating water quality caused by changing weather patterns. The water utility would like to be able to use more of this supply regardless of the weather conditions, which, to Seattle, means having a treatment process downstream that can control for variations associated with weather.

At full capacity, the 120 mgd filtration plant will be able to treat source water of up to 15 NTU of turbidity. It should provide 5 logs removal of Cryptosporidium as well as provide distributed water with less than 64 µg/L total trihalomethanes and less than 48 µg/L haloacetic acids when free chlorine is used for disinfectant residual maintenance.

Source: Adapted from Kelly et al. (1998).

BOX 1-5
Greenville, SC, Water Supply

Drinking water for 250,000 people in Greenville, South Carolina, is supplied by three watersheds: Table Rock, North Saluda, and Lake Keowee. The Greenville Water System (GWS) manages these sources and owns all of the 28,000 acres within the Table Rock and North Saluda watersheds. Table Rock and North Saluda are unfiltered supplies that have a combined capacity of about 15 billion gallons and a total safe yield of about 60 mgd. The quality of water from these two sources has been labeled as "two of the very best, if not the very best, in the United States"

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

(Okun, 1992). In 1993, the watersheds were placed in a conservation easement with The Nature Conservancy.

On December 17, 1991, the South Carolina Department of Health and Environmental Control informed GWS that filtration must be provided for both the Table Rock and North Saluda sources. The reasons for this determination included failure to comply with total coliform standards between April and September 1991, a lack of redundant systems at the disinfection plants, and lack of a watershed control program. In defending the quality of its drinking water, GWS argued that its watershed was wholly owned by the water supplier and that enforcement activities prevented virtually any impacts on the watershed. In addition, GWS outlined a watershed protection and control program targeted at the only known sources of pollution: wildlife, runoff from two state highways, and acid rain.

In 1992, 1993, and 1994, GWS tests revealed additional violations of the Total Coliform Rule (although tests conducted by the South Carolina Department of Health and Environmental Control did not detect coliforms). GWS traced the source of the coliforms to biofilms within the pipes of the distribution system. This prompted EPA Region 4 to insist that plans for filtration of the supplies be accelerated. A detailed schedule for construction of the filtration plants was outlined, including penalties for any violations of the Administrative Order. GWS argued that flushing of the distribution system pipes would be the best method for combating the sources of coliform bacteria and that filtration, because it is upstream of the distribution system, would do nothing to reduce risk from these bacteria. Although GWS charged EPA with several factual errors, it decided not to contest EPA's order in the interest of time and money (GWS, 1995).

The project, consisting of coagulant addition, flocculation, dissolved air flotation, and anthracite mono-medium filtration, is well under way, and filtration should be ready for operation by the end of 1999, in accordance with the Administrative Order. The plant is expected to cost $75 million plus $4 million in annual operating costs. GWS predicts that water rates may be raised by as much as 13 percent to support the project (Thompson, 1993). Meanwhile, according to GWS, flushing of the distribution system has so far proven effective in eliminating detection of total coliform bacteria in the system (Gladfelter, 1995).

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×
  • Comprehensive planning efforts

  • Total Maximum Daily Load program

  • Pilot phosphorus offset program

  • Antidegradation

  • Use of the dual-track approach

  • Buffer zones and setback distances

  • New sewage treatment plants and septic systems

The first five chapters of this report provide background information needed to interpret and assimilate the conclusions and recommendations found in the final seven chapters. Chapter 2 describes the creation of the New York City water supply system and its current configuration and treatment processes, using chronological tables, maps, and system schematics. The chapter closes by summarizing salient biophysical and social characteristics of the upstate watershed region. Chapter 3 outlines the relevant federal, state, and local environmental laws controlling watershed management in New York City and the global public concerns that led to the creation of these laws. Chapter 4 discusses the essential components of an ideal watershed management strategy for source water protection. Although all components are rarely realized in most communities, they are described in detail for comparison to the MOA. Chapter 5 summarizes present-day environmental conditions within the Catskill/Delaware watershed region. Priority pollutants and potential sources of pollution are described. In addition, the current health of the watershed and the water supply are considered by evaluating water quality and compliance monitoring data. This chapter represents a transition between the report's introductory material and its evaluation of various scientific aspects of the MOA. The content of the final seven analytical chapters, organized by topic, is described below. For those readers who turn directly to Chapter 6, the Executive Summary provides a highly abridged version of the background information found in Chapters 15.

Implications of the Safe Drinking Water Act Amendments

The SWTR pursuant to the SDWA provides the regulatory framework that the MOA must satisfy to maintain New York City's waiver from filtration. Changes in the SWTR that may affect the City's waiver are likely to be promulgated within the next two years. Chapter 5 compares current New York City compliance data with projected future regulations in order to assess the City's ability to comply with projected regulatory changes. Special consideration is given to the Enhanced SWTR and the Disinfectants/Disinfection By-Products Rule.

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×
Enhanced Monitoring Program and GIS

NYC DEP maintains a sophisticated monitoring system for measuring changes in water quality throughout the watershed region. Already the subject of external reviews, the adequacy of the enhanced monitoring program is considered in Chapter 6. The chapter builds upon previous studies by making specific suggestions for improving sampling techniques, the timing and numbers of samples taken, and the parameters measured. The different monitoring efforts are framed in terms of the goals they attempt to achieve.

To complement its enhanced monitoring program, NYC DEP is currently organizing its monitoring data for use in a geographical information and modeling system (GIS). Chapter 6 provides recommendations for improving the quality, usefulness, and accessibility of the GIS. Its relationship to other programs within the MOA is explored.

Public Health Protection and Microbial Risk Assessment

Because the end result of watershed management and water supply protection should be the protection of public health among consumers of the drinking water supply, this issue was considered by the committee from multiple viewpoints. First, active disease surveillance being conducted in New York City is evaluated. Chapter 6 considers whether there is adequate data collection on public health outcomes associated with drinking water quality, and it provides recommendations for linking observed gastrointestinal illness to potential drinking water sources. In addition, a quantitative microbial risk assessment is conducted using pathogen monitoring data collected at the source waters of the Catskill/Delaware water supply system. This information reveals potential disease rates that cannot otherwise be ascertained from active disease surveillance. It also highlights data analyses that could be used by New York City to define a baseline level of acceptable risk.

Comprehensive Planning

In order for the counties and municipalities in the watershed to receive certain funds under the Watershed Partnership and Protection Programs, they must develop a cooperative, comprehensive land use plan for water quality protection and growth management. Chapter 7 considers the multiple comprehensive planning efforts that have commenced in both the Catskill/Delaware and Croton watershed regions. These efforts are evaluated for their potential ability to promote environmentally sound economic development within the watersheds.

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×
Total Maximum Daily Load Program

The Total Maximum Daily Load (TMDL) program stems from the Clean Water Act, which requires impaired waters nationwide to be assessed for point and nonpoint source pollutant loading. Although not all are classified as impaired, the 19 water supply reservoirs in the New York City watersheds have been the subject of TMDL calculations for the priority pollutant phosphorus. Chapter 8 reviews the methods used for Phases I and II of this program and provides suggestions for improvement during Phase III. This chapter considers whether phosphorus is the appropriate target of the TMDL calculation and whether existing guidance values for phosphorus should be used.

Phosphorus Offset Pilot Program

One of the most innovative programs found in the MOA is the phosphorus offset pilot program that allows for construction of new wastewater treatment plants (WWTPs) in polluted watersheds. The construction of new WWTPs, or the expansion of existing WWTPs, is allowed if an offset in phosphorus loading can be identified from another source within the same basin. Either a 2:1 or a 3:1 offset ratio must be achieved. This program, and its potential for reducing overall pollutant loading in the watersheds, is evaluated in depth in Chapter 8. The few documented cases of effluent trading are compared to New York City's program to assess potential reliability and enforcement. The chapter provides recommendations on how to improve the program if it is to be implemented at full scale.

Antidegradation

Federal regulations require states to create and implement an antidegradation policy that will prevent further deterioration of water quality in all waterbodies. Although not encompassed by the MOA, antidegradation could be used to enhance the protection currently afforded to the New York City water supply reservoirs. Chapter 8 compares the New York State antidegradation policy to similar policies of other states, focusing on its specific provisions and implementation. The adequacy of New York's antidegradation policy is assessed by evaluating two state regulations used to carry out antidegradation: the State Environmental Quality Review Act and the State Pollutant Discharge Elimination System (SPDES) permitting program.

Dual-Track Approach

As part of its filtration avoidance determination, New York City must simultaneously plan for the construction of a filtration plant while implementing the watershed protection program. Chapter 8 considers the merits of this ''dualtrack" approach and compares it to the multiple-barrier approach strongly

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

endorsed by EPA and the American Water Works Association. Pilot filtration studies and studies on alternate disinfectants are both reviewed.

Buffer Zones and Setback Distances

One of the committee's most challenging tasks was to assess the capability of setback distances for improving water quality in the water supply reservoirs. Setback distances ranging from 25 feet to 1,000 feet are evaluated in Chapter 10 for their ability to remove such pollutants as phosphorus, sediment, pesticides, and landfill leachate. Several suggestions are given for managing setback areas to achieve the greatest pollutant removal possible. In addition, the constitutionality of requiring setbacks, and the use of setbacks in other states, is presented for comparison with the MOA.

Setback distances and buffer zones represent only one specific type of BMP used to control nonpoint source pollution. Thus, Chapter 9 considers the wide variety of BMPs used throughout the watershed region and their implementation. The discussion is organized around three important programs designed to limit nonpoint sources of pollution: the Watershed Agricultural Program, the Watershed Forestry Program, and Stormwater Pollution Prevention Plans.

New Sewage Treatment Plants and Septic Systems

Because of its potential for introducing pollutants into the watershed, wastewater is the focus of multiple programs under the MOA. The MOA imposes technology and effluent standards and siting requirements for new WWTPs as well as siting requirements for septic systems, also known as on-site sewage treatment and disposal systems (OSTDS). Chapter 11 analyzes the relative impact of new WWTPs and OSTDS on overall water quality under current and future conditions. In addition, it considers the suitability of rules that govern the locations of these wastewater treatment systems. The chapter provides recommendations regarding technology requirements for WWTPs and OSTDS, and it provides an evaluation of the adequacy of effluent standards for WWTPs.

In making its assessments of the MOA, the committee attempted to consider long-, mid-, and short-term impacts to the water supply system. Important long-term considerations include (1) the discovery of scientific information relating various physical, chemical, and biological components of water quality to human health, (2) evolving federal public policies and regulatory frameworks, (3) the changing demand for water from these watersheds over time, (4) the value of preserving natural ecosystems within the watersheds for water quality-related and other reasons, and (5) the pressures of economic change within the watersheds. Midterm events that can substantially affect the water supply system and the watershed management strategy include hydrologic conditions such as sus-

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

tained drought and fluctuations in wastewater discharge caused by the large seasonal population of the Catskill/Delaware watershed region. Finally, short-term impacts that must be taken into account include severe storm events, possible terrorist activities, and accidents such as chemical spills. These considerations define special management challenges that may be materially affected by the strategy chosen to protect the drinking water supply.

Transferability of Report Contents

Although no other community and its water supply is quite like New York City, information within this report applies to other communities that use surface water sources for drinking water supplies. Watershed management for protecting surface water supplies (source water protection) is valuable as a first barrier, regardless of the treatment technologies that are subsequently applied. Chapter 4 provides guidance to help communities implement various elements of a source water protection program, a "how to" for source water protection that has not been presented elsewhere. Most watershed management publications focus on regulatory requirements or on case studies of how communities have gone about developing source water protection programs. In this report, more general advice and guidance are given for communities embarking on similar programs.

Many of the ideas presented in this report have relevance for a wide range of conditions that various water supplies might face, including pristine supplies that are wholly owned and protected by the surface water supplier, largely uncontrolled watersheds, and transbasin watersheds that are far removed from the water supplier's jurisdiction. The key lessons and areas of information within the report that are particularly transferable are as follows:

  • Chapter 4 presents a generic framework for watershed management for source water protection, discussing several necessary components. Two components that are often overlooked are (1) goal setting to provide the foundation for a sound program and (2) effectiveness monitoring to measure the success of programs. Examples of full-scale implementation mechanisms are also presented.

  • A detailed description of potential drinking water quality constituents of concern in the New York City watersheds is found in Chapter 5. These constituents are common pollutants in other surface water supplies as well.

  • Chapter 6 discusses the elements of a monitoring program to support source water protection, including means to check program effectiveness.

  • Innovative policies to support source water protection efforts across the country are explored and reviewed in Chapter 8, such as effluent trading and the TMDL concept.

  • Nonpoint source practices for source water protection, including recommended programs for septic system improvements to protect drinking water supplies, are discussed extensively in Chapters 911.

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

REFERENCES

Coombe, R. 1998. Watershed Agricultural Council. Presentation given at the third NRC Committee Meeting, May 13–16, 1998, Oliverea, NY.

Cronin, J., and R. F. Kennedy. 1997. The Riverkeepers. New York, NY: Scribner.


DelVecchio, J. R. 1997. The Agricultural Program to Protect the Drinking Water of New York City. In Proceedings of the 5th National Watershed Conference. Reno, NV.


Environmental Protection Agency (EPA). 1993. The Watershed Protection Approach. EPA 840-S-93-001. Washington, DC: EPA.

EPA. 1996. Watershed Approach Framework. Washington, DC: EPA.

EPA. 1997a. New York City Filtration Avoidance Determination. New York, NY: EPA.

EPA. 1997b. Notice of Data Availability ESTWR. Washington, DC: Office of Water, EPA.


Finnegan, M. C. 1997. New York City's watershed agreement: A lesson in sharing responsibility. Pace Environmental Law Review 14:577-644.


Gladfelter, Melinda. 1995. Water System Ordered to Monitor for Illnesses. The Greenville News.

Greenville Water Supply (GWS). 1995. Watershed Protection Program. Greenville, SC: Greenville Water System.

Goldstein, E. 1997. Natural Resources Defense Council. Presentation given at the first NRC Committee Meeting, September 25–26, 1997, New York, NY.


Hazen and Sawyer/Camp Dresser and McKee. 1997. The New York City Water Supply System. New York, NY: Hazen and Sawyer/Camp Dresser and McKee.

Howe, P. J. 1999. Judge Orders Trial in Water Quality Dispute. The Boston Globe. Friday, May 7, 1999.

Hutchinson, D. P. 1993. A Setback for the Rivers of Massachusetts? An Application of Regulatory Takings Doctrine to the Watershed Protection Act and the Massachusetts Rivers Protection Act. Boston University Law Review 73:237–270.


Kelly, E. S., S. Haskins, and P. D. Reiter. 1998. Implementing a DBO project. Journal of the American Water Works Association 90(6):34–46.


Marx, R., and E. A. Goldstein. 1999. Under Attack: New York's Kensico and West Branch Reservoirs Confront Intensified Development. New York, NY: Natural Resources Defense Council.

Metropolitan District Commission/Massachusetts Water Resources Authority. 1991. Watershed Protection Plan: Wachusett Reservoir Watershed. Boston, MA: MDC/MWRA.


National Research Council (NRC). 1999. New Strategies for America's Watersheds. Washington, D.C.: National Academy Press.

New York City Department of Environmental Protection (NYC DEP). 1990. Discussion Draft of Proposed Regulations for the Protection from Contamination, Degradation and Pollution of the New York City Water Supply and Its Sources. Corona, NY: NYC DEP.

NYC DEP. 1993a. Draft Generic Environmental Impact Statement for the Draft Watershed Regulations for the Protection From Contamination, Degradation, and Pollution of the New York City Water Supply and Its Sources. Corona, NY: NYC DEP.

NYC DEP. 1993b. Watershed Protection through Whole Community Planning: A Charter for Watershed Partnership. Ithaca: New York State Water Resources Institute, Center for the Environment, Cornell University.

New York City Office of the Comptroller. 1997. Avoiding Disaster: The Need to Make the Upstate-Downstate Watershed Protection Partnership Work. New York, NY: New York City Office of the Comptroller.


Okun, D. 1992. Remarks on the Greenville Watersheds. In Properties of the Table Rock and Point Set Reservoirs: Their Future. Greenville, SC: Greenville Watershed Study Committee.

Okun, D. A., G. F. Craun, J. K. Edzwald, J. R. Gilbert, E. Pannetier, and J. B. Rose. 1993. Report of the Expert Panel on New York City's Water Supply. Washington, DC: EPA.


Paden, C., and A. Shen. 1995. New York City water under pressure. Inside DEP 1(1):1–8.

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

Pfeffer, M. J., and L. P. Wagenet. 1999. Planning for Environmental Responsibility and Equity: A Critical Appraisal of Rural/Urban Relations in the New York City Watershed. Pp. 179–205 in Lapping, M. B., and O. Furuseth (eds.), Contested Countryside: The Rural Urban Fringe of North America.

Platt, R., and V. Morrill. 1997. Sustainable water supply management in the United States: Experience in metropolitan Boston, New York, and Denver. Pp. 292–307 In Shrubsole, D., and B. Mitchell (eds.) Practicing Sustainable Water Management: Canadian and International Experiences. Cambridge, Ontario: Canadian Water Resources Assn.

Postel, S. 1992. Last Oasis: Facing Water Scarcity. New York and London: W. W. Norton.

Schneeweiss, J. 1997. Watershed protection strategies: A case study of the New York City Watershed in light of the 1996 Amendments to the Safe Drinking Water Act. Villanova Environmental Law Journal. 9:77–119.

Stave, K. A. 1998. Water, Land, and People: The Social Ecology of Conflict over New York City's Watershed Protection Efforts in the Catskill Mountain Region, NY. Ph.D. Dissertation, Yale University.


Thompson, S. 1993. Panel Considers 13% Water Hike. Greenville Piedmont. October 11, 1993.

Suggested Citation:"1 The Problem." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
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In 1997, New York City adopted a mammoth watershed agreement to protect its drinking water and avoid filtration of its large upstate surface water supply. Shortly thereafter, the NRC began an analysis of the agreement's scientific validity.

The resulting book finds New York City's watershed agreement to be a good template for proactive watershed management that, if properly implemented, will maintain high water quality. However, it cautions that the agreement is not a guarantee of permanent filtration avoidance because of changing regulations, uncertainties regarding pollution sources, advances in treatment technologies, and natural variations in watershed conditions.

The book recommends that New York City place its highest priority on pathogenic microorganisms in the watershed and direct its resources toward improving methods for detecting pathogens, understanding pathogen transport and fate, and demonstrating that best management practices will remove pathogens. Other recommendations, which are broadly applicable to surface water supplies across the country, target buffer zones, stormwater management, water quality monitoring, and effluent trading.

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