Covered by forests, meadows, marshes and swamps and intersected by streams that eventually emptied into their larger cousin, the Bronx River watershed or drainage basin was similar to most of Westchester County. Over time after European settlement, new farmland gave way to paved roads, parking lots and buildings of all kinds. Today, the watershed is considerably developed, especially in southern Westchester. Low-, moderate- and high-density housing, shopping centers, offices, industry and other similar land uses have replaced many of the natural resources that once dominated the landscape. Even recreational uses, like golf courses and athletic fields, have altered the landscape.

Unlike the forests and wetlands they replaced, parking lots, office buildings, shopping centers, factories, etc. do not absorb the rainfall and melting snow that runs over and through them. Instead, they shed the water, increasing the volume and often the rate at the which stormwater runoff enters streams and rivers, causing flooding. They also add pollutants like oils and grease, metals and salts and nutrients like nitrogen and phosphorus. This polluted stormwater runoff then washes into catch basins and other stormwater infrastructure, where it may go untreated directly into the river and its tributaries. This adds to the degradation of water quality, thereby impeding the river’s ability to host fish and wildlife and recreational pursuits, like fishing and swimming.

The Bronx River Watershed Coalition was formed in 2003 as a partnership among Westchester County municipalities and agencies and not-for-profit organizations seeking the same goal: to improve water quality in the Bronx River. It also helped address flood mitigation. Over time, state and New York City agencies joined the effort. The coalition developed a comprehensive watershed plan, which lays out a strategy for limiting the amount of stormwater runoff and pollutants entering the Bronx River and its tributaries.

The Coalition developed a Stormwater Pollution Control Plan (Volume 1) and Wetland Field Assessment and Management Plan (Volume 2) under the overall Bronx River Watershed Management Plan in 2007.

Please also see the Bronx RiverCorridor Study and Management Plan for Westchester County, NY - Voulme 1 (July 2019)

Bronx River Corridor Study and Management Plan for Westchester County, NY – Volume 2 (May 2020) and Bronx River Corridor Study and Management Plan Appendices – Volume 2 (for more information about this volume or to obtain a copy, please contact Nicole Laible at This email address is being protected from spambots. You need JavaScript enabled to view it.)

Bronx Rivers Dams Management Plan is available.  For more information or to obtain a copy, please contact Nicole Laible at This email address is being protected from spambots. You need JavaScript enabled to view it.

Coalition members included municipalities in Westchester County whose boundaries fall wholly or partly within the Bronx River watershed:

Other members include the:

The Center for Watershed Protection, Biohabitats, and Northern Ecological Associates assisted staff of the Westchester County Department of Planning in developing the Bronx River Watershed Management Plan. The U.S. Army Corps of Engineers, New York District, and Westchester County Department of Health and Department of Laboratories and Research also provided assistance.

For further information on watershed planning efforts concerning the Bronx River, contact:

Nicole Laible, Principal Environmental Planner
E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
Tel: (914) 995-4423 Fax: (914) 995-3780

The goal of the Septic System Rehabilitation and Sewer Connection Program is to reduce the potential health and environmental impacts that may arise from failing septic systems and the associated discharge of sewage effluent into the Croton and Kensico watersheds, also known as the NYC watershed. This shall be accomplished by providing financial assistance to income eligible commercial and non-commercial property owners who have an on-site septic system in the watershed and meet one of the following two criteria: 1) a property line within 100 feet of a sewer line, 2) with a failing septic system for which there is no available sewer line within 100 feet from the property line for three (3) years from the year the application is submitted.

Application and Info guide

Westchester Couty Department of Health Septic Systems Information

Licensed Septic Contractors

Professional Engineer and Licensed Architects

For more information contact Program Coordinator, Millie Magraw by e-mail This email address is being protected from spambots. You need JavaScript enabled to view it. or by phone at (914) 995-2090.

The county takes the lead in protecting its watershed areas. Watershed protection is by necessity a major concern in the county. The large number of reservoirs provide drinking water for residents living in Westchester, New York City and several cities in Connecticut. Two estuaries, Long Island Sound and lower Hudson River, provide numerous recreational and economic development opportunities to the entire metropolitan area, making their preservation all the more critical.

Westchester has six major drainage basins. View watersheds map.

Westchester's major watershed areas are:

• Peekskill & Haverstraw Bay
• Croton River
• Pocantico & Saw Mill River
• Inland Long Island Sound
• Bronx River
• Coastal Long Island Sound

The largest reservoir system in the county is part of the New York City water supply system which has three components, the

• Croton Reservoir Source System, which covers 18,000 acres of land and water surface in Westchester plus additional areas of Putnam County
• Catskill system
• Delaware system

Water from the two upstate systems passes through Westchester via aqueducts and the Kensico Reservoir on the way to New York City. The city’s system provides water to 85% of Westchester’s residents.
 
The Planning Department played a lead role in the Croton/Kensico watershed negotions between the 12 Westchester County municipalities and New York City, which resulted in the historic NYC Watershed Memorandum of Agreement of 1997. Westchester County continues to provide leadership for its 12 watershed municipalities. 

The Bronx River Watershed Coalition, formerly known as Watershed Advisory Committee 7 of the Long Island Sound Watershed, was formed in 2003 as a partnership among Westchester County municipalities and agencies and not-for-profit organizations seeking the same goal: to improve water quality in the Bronx River. Over time, state and New York City agencies joined the effort, too. The coalition sought to achieve its goal by developing a comprehensive management plan, available on this website, which lays out a strategy for limiting the amount of pollution entering the river and its tributaries via stormwater runoff.

Planning Department staff continues to provide administrative and technical support to 19 Westchester County municipalities in the Long Island Sound watershed, promoting water quality and fish and wildlife habitat efforts. The county's nonpoint source pollution control efforts, which dovetail with the Long Island Sound Study, have focused on intermunicipal watershed planning and public outreach/education since 1995. More recent efforts have implemented the watershed management plans, including aquatic restoration. For more information, read about the Long Island Sound Watershed and the Aquatic Restoration programs.

The Indian Brook-Croton Gorge Watershed Conservation Action Plan is a comprehensive watershed plan developed for the Croton Bay Watershed, which consists of the Croton Gorge and Indian Brook subwatersheds. The county produced the report in close collaboration with the towns of Cortlandt, New Castle, Ossining and the villages of Croton-on-Hudson and Ossining. 

The county has always incorporated the latest technology and information in its capital program to reduce costs, improve efficiency, and reduce environmental impacts.

Currently, there is a heightened awareness of developmental impacts on air and water pollution, climate change, and energy costs. This has resulted in stricter environmental and performance standards for buildings and the creation of building rating programs such as Leadership in Energy and Environmental Design (LEED). The building techniques used to achieve these standards are often referred to as “Green Building” techniques.

The county incorporates green building techniques into its capital projects and explores the use of new technologies where appropriate. County employees are educated on green building technologies and look for grant funding wherever possible to reduce the costs of construction, particularly when utilizing newer technologies with shorter performance records. The county engineers the highest performance in the buildings it constructs and manages and promotes green building techniques for funded construction projects.

More information on green building techniques and LEED standards can be found at the U.S. Green Building Council and the EPA Green Building Web sites.