Main Banner

NEWS from the Office of the New York State Comptroller
Contact: Press Office 518-474-4015


DiNapoli: Contamination of New York's Waterways From Combined Sewer Overflows Remains a Challenge

May 10, 2018

Last year, billions of gallons of untreated sewage and stormwater impacted more than 200 waterways in New York due to antiquated and overwhelmed sewer systems, according to a report released today by State Comptroller Thomas P. DiNapoli.

"When billions of gallons of untreated waste spills into New York's waterways, our health, environment, economy and quality of life suffer," said DiNapoli. "State and local governments must remain focused on addressing the challenges of aging infrastructure through continued funding for these priorities, thoughtful capital planning and more sustainable development."

DiNapoli's report details the problems with combined sewer overflows (CSOs) in the state. Most large urban areas in New York state are served by municipal sewer systems, many of which commingle the water from rain and snow melt with the wastewater from homes and businesses in combined sewer systems.

There are 46 CSO communities in New York responsible for 807 outfalls – locations where excess untreated or partially treated combined sewer wastewater is discharged from pipes directly to rivers, streams, estuaries and coastal waters when their systems are overwhelmed. New York City is responsible for about half of the outfalls, and just three other metro areas (Albany, Syracuse and Buffalo) make up nearly another quarter of the total.

The problem itself is not new but there is an even greater urgency to address it with the increased frequency of intense wet weather events. The discharges from combined sewers have harmful effects that residents need to be notified of quickly, so recent state regulations now require sewer system owners to report all discharges of untreated or partially treated waste into waterways in real time.

In state fiscal year 2016-17, sewer system operators reported a total of 1,900 unique overflow events, 87 percent of which made contact or potentially made contact with a waterway.

During this period, however, 10 percent of the overflow reports excluded a required volume estimate altogether or reported it erroneously, according to the state Department of Environmental Conservation (DEC). Using this data, DEC estimated that the total volume of discharge of partially or untreated wastewater during 2016-17 was 6.5 billion gallons affecting about 220 bodies of water.

Combined sewer discharges can have negative effects on the environmental health of waterways and their ecosystem. Contaminants can make a river, stream, lake or shoreline unfit for swimming or fishing, and can also impact drinking water supplies. Across New York, the closing of beaches for high levels of bacteria such as E. coli has become almost commonplace.

Full scale replacement of combined sewers with separated sanitary and storm sewers is costly and the associated construction can be disruptive. In 2012, the U.S. Environmental Protection Agency estimated the cost of CSO corrections in New York would exceed $5 billion over 20 years. This is in addition to the $26.3 billion the EPA estimates is needed for other wastewater infrastructure improvements.

A number of communities have pursued improvements through separating some wastewater flows, installing holding tanks to store stormwater, developing green infrastructure that soaks up rainfall and releases it slowly, and retrofitting sections of sewer and treatment infrastructure.

Infrastructure improvements are often aided by state and federal financing measures. These include:

  • The New York's Environmental Facilities Corporation plans to make approximately $903 million available in low-cost financing through the Clean Water State Revolving Fund (CWSRF) to finance upgrades to wastewater systems, including combined sewer systems.
  • Green Innovation Grants, a program supported by the CWSRF, are available for environmentally-friendly projects that improve water quality through projects such as rain gardens and stream bank stabilization.
  • The New York State Clean Water Infrastructure Act of 2017 authorized an investment of $2.5 billion in clean water and drinking water infrastructure projects and water quality protection over multiple years.
  • This year, the state announced a $65 million effort to study and remediate the issue of harmful algal blooms.

To guide investments in the most pressing capital projects that are significantly funded with state resources, DiNapoli has proposed the creation of a New York State Capital Asset and Infrastructure Council. The council, combined with a statewide capital needs assessment, would allow policy makers to prioritize those assets most in need of repair and most critical to the economy.

The report is the latest in a series by DiNapoli examining infrastructure in New York. A copy of the report, which includes a full list of municipal CSOs in the state, can be found online:

Find out how your government money is spent at Open Book New York. Track municipal spending, the state's 145,000 contracts, billions in state payments and public authority data. Visit the Reading Room for contract FOIL requests, bid protest decisions and commonly requested data.