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For Release: Thursday, May 31, 2012

New York State, New York City Announce One-Year Renewal of Current Multi-State Water Management Agreement

New York State Department of Environmental Conservation (DEC) Commissioner Joe Martens and New York City Department of Environmental Protection Commissioner Carter Strickland, along with Pennsylvania, New Jersey and Delaware, announced that they have unanimously agreed to a one-year extension of the current water-management agreement for the Delaware River reservoirs. The agreement will continue to protect fisheries habitat in the Delaware River and seek to mitigate peak flood levels, while preserving New York City's ability to provide adequate amounts of high quality water to more than nine million New Yorkers.

"Expert State and City staff has developed a progressive water management program that allows for improvements to habitat and enhanced flood mitigation," said Commissioner Martens. "There are important, and sometimes competing, interests affected by the allocation of the waters of the Delaware River Basin. DEC is committed to working with our partners and stakeholders to maximize benefits for all while assuring the protection of this critical supply of drinking water."

"This important agreement enables us to refine our use of the Operations Support Tool (OST), DEP's cutting-edge decision support system. OST combines real-time data collection, state-of-the-art river forecasts, and computer modeling to enhance water supply reliability for NYC while allowing DEP to make reservoir releases to support river ecology and other down basin needs, and to mitigate flood risk for Delaware Basin communities," said DEP Commissioner Carter Strickland. "I thank DEP's partners in the Delaware River Basin Commission for their commitment to a renewed effort on this critical issue, and DEP looks forward to continuing this productive partnership."

The water-management plan is based on a progressively evolving mathematical computer model, called the OST. The model provides good information on when it is safe to release water without unnecessarily increasing risk to the public water supply. The model accounts for the different factors that managers must consider when making releases, such as actual and predicted rainfall, the amount of water flowing into the reservoirs, and the amount of water already stored in the reservoirs. Data is gathered continuously which allows managers to make better decisions on the rates of water releases. The final version of the model is due out in the fall of 2013.

By using this model, New York City has been able to allow more water to be released from their reservoirs into the Delaware River. The increased flow supports the fishery and other activities along the river. Increased void space in reservoirs helps to attenuate peak flows during storm or snow melt events. The release rates in the renewed one-year agreement continue to be patterned after these recommendations.

Under the plan:

  • New York City will continue to target lower reservoir storage levels during some seasons so that stormwater has a place to go during storm events. The intent is to enhance flood mitigation that the reservoirs already provide during extreme weather conditions.
  • Continued protection is provided for Philadelphia's water supply from salt water intrusion. The agreement will maintain the flow in the Delaware River which repels the salt front coming up the River from the Atlantic Ocean.
  • Continued protection is provided for the public drinking water supply for New Jersey during drought conditions.

Since 1961, New York State, New York City, New Jersey, Pennsylvania and Delaware have worked together to manage the water resources in the Delaware River Basin. The agreement balances the river's ever-changing economic and environmental factors all within a legal framework set forth by the U.S. Supreme Court. Since the 1970s, the parties have worked to address the issue of the amount of water flowing from New York City's three reservoirs into the Delaware River and to balance New York City's drinking water needs with the many other competing needs throughout the basin.

Additional details, including the Flexible Flow Management Program agreement and OST background information, can be viewed on the web site of the Office of the Delaware River Master (link listed in the right column), which administers the provisions of the 1954 U.S. Supreme Court Decree.