New York City drinking water supply and quality report 2021

In 2021, the Department of Environmental Protection (DEP) continued its mission to deliver top-quality tap water to over 9.8 million New Yorkers, despite numerous challenges. DEP monitors water quality across the distribution system, reservoirs, feeder streams, and wells, investing heavily in infrastructure upgrades. Major projects include work on the Catskill and Delaware aqueducts, with over $1 billion dedicated to watershed protection and pollution prevention programs.

The DEP collected 44,300 samples and performed 556,000 analyses in its laboratories, while robotic stations conducted 2.9 million tests to ensure water quality. New York City’s water system, which serves nearly half of New York State’s population, draws from 19 reservoirs and three controlled lakes in a 2,000-square-mile watershed.