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Welcome to the Office of the Delaware River Master (ODRM)

The Office of the Delaware River Master was established to ensure compliance with the provisions of the 1954 Supreme Court Decree, subject to modifications stemming from more recent Flexible Flow Management Programs, and compilation of data concerning related streamflow, reservoir releases, and water diversions.

NEW UPDATE: Operation of the NYC Reservoirs without a Flexible Flow Management Program

Conservation releases from the NYDEP reservoirs continue temporarily at levels previously agreed to under the 2016 Flexible Flow Management Program (FFMP) while the Decree Party Principals continue discussions related to a possible 2017 FFMP. Other aspects of the reservoir management program continue under the guidance of the Delaware River Basin Commission "Water Code" the Revision 1, and the 1954 Delaware River Supreme Court Decree as described here. (URL:

Rev 1 provides for thermal – relief releases under the authority of the New York Department of Environmental Conservation (NY DEC). In response to high temperatures, NY DEC has directed thermal – relief releases beginning June 12.

As flows continue in excess of the Montague flow objective, there have been no directed releases from the Office of the Delaware River Master.

Operation of the NYC Reservoirs without a Flexible Flow Management Program

The Flexible Flow Management Program (FFMP) expired at midnight on May 31, 2017 without a replacement or extension. Absent the FFMP or a similar agreement, provisions included in the 1954 Supreme Court Decree, the Delaware River Basin Water Code, and Docket D77-20 CP Revised (Rev 1) now guide operations of the New York City (NYC) reservoirs in the headwaters of the Delaware River Basin (Cannonsville, Pepacton, and Neversink). These provisions apply to operations during normal hydrologic conditions and drought, and include special releases for thermal relief and management of the "excess release quantity" (ERQ). There are no provisions for spill mitigation or enhanced habitat protection, other than thermal relief.

The parties to the 1954 Supreme Court Decree are scheduled to meet later in the month and expect to discuss a path to create a framework to better address the management of the reservoirs, the sharing and protection of the water resources of the Delaware River Basin in a fair and equitable manner, and the diverse needs and multiple objectives of the parties, stakeholders, and the public.

Absent the FFMP, the most notable difference in reservoir operations will be in the conservation releases. Under most hydrologic conditions, the conservation releases from the NYC reservoirs will be less than those in the FFMP. There will be limited flexibility to address unique hydrologic conditions or events except for a bank of water for special thermal stress releases to protect the fisheries. During drought conditions, flow targets and out of basin diversions will be reduced in accordance with prevailing hydrologic conditions in the basin, as described in the Delaware River Basin Water Code.

The Decree Party Principals, officials of the Delaware River Basin Commission, and the River Master have reviewed the 1954 Supreme Court Decree, the Delaware River Basin Water Code and Docket D77-20 CP Revised (Rev 1), which will control the operation of the NYC reservoirs in the absence of a signed FFMP. Based on that review and related discussions, the River Master has prepared a general prospective on reservoir operations without an FFMP. The prospective is summarized and posted on the Office of the Delaware River Master webpage under the Flexible Flow Management Program (FFMP) and Background Documents.

Provisional Hydrologic Data:

Data presented on the Office of the Delaware River Master website are reviewed periodically to ensure accuracy. The data are considered provisional, however, until they are published in the annual report of the River Master.

Data users are advised to carefully consider the provisional nature of the information before using it for decisions that concern personal or public safety or the conduct of business that involves substantial monetary or operational consequences.

Information on the accuracy and appropriate uses of the data can be obtained by contacting the Deputy Delaware River Master.

Flexible Flow Management Program (FFMP) and Background Documents

As part of the FFMP agreement, the New York State Department of Environmental Conservation (DEC) monitored the releases program to evaluate its effectiveness in protecting the coldwater ecosystem below the reservoirs. This report, NYSDEC Tailwaters Temperature Monitoring Report for June 2011 through May 2015, prepared by the DEC, summarizes the summer water temperatures observed under the one­year FFMP agreement extensions in effect between June 1, 2011 and May 31, 2015. Thermal data were obtained from eight permanent USGS gages and 21 Onset Optic “Stow Away” thermographs installed and maintained by DEC staff on the upper East Branch, West Branch, Delaware River, and Neversink River. The report concludes that:

Overall, the FFMP releases program was effective in maintaining flow and temperature targets in the Upper East Branch, West Branch, and Neversink River tailwater reaches. No thermal stress days were recorded for the Upper East Branch or the West Branch and only 7 in 2012 in the Neversink River. FFMP summer base flows to the West Branch were inadequate in maintaining desirable summer water temperatures in the upper Delaware River but this was also true of all earlier releases programs. Directed releases to meet the Supreme Court mandated Montague flow target continue to exert the greatest influence on summertime temperature and flow conditions on the West Branch and upper Delaware River. Thermal stress days on the Delaware River for the summers of 2011 through 2014 ranged from 0 to 13 at Lordville (RM 321) and 5 to 67 at Callicoon (RM 303).

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