HAA5 compounds form from the reaction between chlorine and natural organic matter such as from decaying leaves and vegetation.

The HAA5 compounds that have have been detected in WJWW’s water supply system are a common by-product of the water disinfection process, as they form when chlorine reacts with naturally occurring organic matter in untreated surface water.

Filtering the water is a proven treatment to reduce the formation of HAA5 compounds by removing organic matter that is naturally found in untreated water. ​WJWW has a plan in place to build a Water Filtration Plant for its Rye Lake water source to comply with state and federal orders to address potential public health risks.

We understand the urgency of this effort and must take action to ensure clean, reliable drinking water continues to be delivered to consumers without further delays.

WJWW is Lead Agency on this project under the State Environmental Quality Review Act (SEQRA), with the expertise and resources to ensure compliance and a thorough environmental review in collaboration with an expert team of environmental engineers, planners, scientists, architects, government agencies and legal specialists.​

Filtration will function as the primary source of treatment and be supplemented by existing treatment measures. This is the most effective method of protection for WJWW to provide safe, clean drinking water now and into the future.

The Water Filtration Plant will be located adjacent to Westchester County Airport, on a parcel of land bordered by Purchase Street and the private aviation hangars occupying the southwest corner of the airport. A minimum 100-foot forest buffer will exist between the property line and the new building. The distance between Purchase Street and the proposed facility is approximately 170 feet at its closest point. The building’s architectural features have been designed to mitigate height and length perception, and the building will incorporate a range of sustainability features.


WJWW has been advancing the design of a Water Filtration Plant to provide proven treatment technology for the Rye Lake water supply to meet New York State and U.S. Environmental Protection Agency orders.

The site will be thoughtfully laid out using a range of screening features in conjunction with new landscape plantings.

The Purchase Street entrance will feature stone piers, estate-type gates, enhanced landscape design and bioswale elements to blend with the existing area. Portions of a historic stone wall along the east side of Purchase Street will be repaired and sensitively incorporated into the entry design. The entrance will include a central landscape medium with mature trees and additional features that will serve to mask direct views into the site and building beyond.

A substantial portion of the Water Filtration Plant will be underground, not visible to the public.

The periphery of the filtration plant site will include strategically placed landscape elements to enhance the appearance and appropriate levels of lighting that will not intrude on the surrounding area. Although sound from the plant processes is minimal, additional sound-dampening features will be included in the design.

The result will be an environmentally friendly and attractive facility that blends into the surrounding area and, most important, provides for critical infrastructure and processes to support safe, clean water well into the future.