Is Poor Maintenance of Rooftop Water Tanks Endangering New York City's High Quality Drinking Water?


There is an important exposé in today's New York Times, which should be of interest to city apartment dwellers whose drinking water travels through New York's iconic rooftop water towers.

An investigation by Times reporters Ray Rivera, Frank G. Runyeon and Russ Buettner has found muddy sediment and e-coli bacteria accumulated at the bottom of some water tanks that the Times recently sampled in Manhattan, Queens and Brooklyn. In addition, the Times reports, such water tanks may not have been cleaned or inspected for years, in apparent violation of the City’s health code. 

To be sure, the sediment and bacteria identified in its twelve building-sample were located at tank bottoms -- below the the pipe outlets that funnel water from the tanks into building apartments. And New York City Health Department officials have told the Times that these systems are safe and that they have found no evidence of associated health problems. 

Still, the revelations are troubling, especially for a city that prides itself on its world-class water supply. While the facts as uncovered by the Times are not grounds for panic, they certainly call for aggressive follow-up action by appropriate government agencies.


New York City’s high quality drinking water supply may be a risk as a result of poor maintenance by property owners of their rooftop water towers, according to a New York Times investigation. Based upon the Times’ revelations, NRDC is calling upon the New York City Health Department to begin immediate inspections of water towers across the City and to take aggressive follow-up enforcement action as warranted.


New York City's well-regarded drinking water supply is drawn primarily from six giant upstate reservoirs located as far as 125 miles away in the Catskill Mountains. From there, the water travels via underground aqueducts, tunnels and ultimately smaller water mains into every city neighborhood.

For nearly two decades, the city, state, and federal governments (along with the local watershed communities that surround these Catskill/Delaware reservoirs) have cooperated in the implementation of a comprehensive program to prevent pollution from entering our reservoirs and to safeguard drinking water quality as required by the federal Safe Drinking Water Act.  

The City’s Department of Environmental Protection is regularly testing this water -- at our reservoirs, as it enters the distribution system and at monitoring points throughout the city -- to insure that it meets federal and state drinking water standards. And such testing continues to show that the overall quality of water being delivered by the city’s network remains high and in compliance with state and federal health regulations.

But once this water enters the service lines and pipes that carry it into our individual homes and apartments, assuring water quality becomes the primary responsibility of property owners. And here, according to the Times, is where the problem may be present.  For private homes and buildings of five floors or less, city water flows directly into pipes that carry it to individual bathrooms and kitchens (without reliance on rooftop water tanks). But to insure proper water pressure for most buildings six stories or higher, electric pumps are used to send water up to large rooftop tanks, where the building’s water supply is held before ultimately being funneled through distribution pipes into individual apartments.

The New York City Health Code contains provisions that are designed to insure that such rooftop water tanks operate safely and preserve the high quality water that is delivered to them from the city’s upstate reservoirs. Specifically, the code requires that owners of buildings that are equipped with rooftop drinking water storage tanks must inspect such tanks at least annually, and sample tank waters for bacteria. The code further requires that the results of such inspections must be maintained by building owners for at least five years and made available both to the Health Department and to building residents, upon request. New York City Health Code, Article 141.07. 

Finally, according to the Health Code, where any such inspection “identifies any unsanitary condition, the owner … shall take the necessary steps to immediately correct the condition.”

It seems obvious from the story in today’s Times and from the accompanying, top-notch video, which may be found on the New York Times website, that these Health Code provisions are not adequately being enforced today in New York City. 

And the systematic failure to insure that all rooftop water tanks in New York City are regularly maintained and kept in a state of good repair represents an unnecessary risk to public health.

Accordingly, NRDC is today sending a letter to the New York City Health Commissioner, calling for immediate action in the form of accelerated inspections by the city of rooftop water tanks in all five boroughs.  

NRDC is sending a second letter today to the U.S. Environmental Protection Agency’s New York office, asking that the federal agency undertake an independent review of this situation and make such recommendations to the New York City Health Department as may be necessary to insure that the goals and objectives of the federal Safe Drinking Water Act are fulfilled.

Over the last decade and a half, New York City’s upstate drinking water supply has been protected through cost-effective watershed protection and pollution-prevention efforts that have become a national model. It would be ironic indeed if this reputation (and the health of apartment dwellers) were to be placed at risk as a result of the failure of property owners to perform routine maintenance on the rooftop water tanks that frame the city’s skyline.