Department of Environmental Conservation

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Managing Water Resources

DEC has programs that manage dams, other infrastructure, and water supply and programs that protect New Yorkers from coastal and inland flooding.

Groundwater Programs and Information

Water Withdrawal and Conservation

DEC programs for protecting New York's water supplies include:

In addition, in accordance with the Great Lakes Compact (PDF) (92 KB), diversions of water and wastewater from the Great Lakes Basin are prohibited.


Groundwater is a critical source of water in New York State. Learn about groundwater:

Flood Risk Reduction Programs

Flood Protection and Floodplain Management

DEC works with communities throughout the state to find ways to reduce or protect against loss of life and property damage caused by flooding. DEC has floodplain management and protection programs that focus on:

Coastal Erosion

Coastal erosion is a naturally occurring process that results in the loss or displacement of land along the coastline, which is continually changing natural protective features such as beaches, dunes, bluffs and nearshore areas.

DEC has two programs focused on the protection of coastal erosion: Coastal Erosion Hazard Area (CEHA) permit program and the United States Army Corps of Engineers (USACE) Civil Works Program. CEHA regulates and issues permits for activities within New York State's coastal erosion hazard areas. DEC also works with USACE to study coastal erosion problems along NYS coastlines and to develop coastal erosion solutions.

Dam Safety

The Dam Safety program is responsible for regulatory dam safety inspections, technical review of proposed dam construction or modification, monitoring remedial work for compliance, monitoring owner dam safety activity, and emergency preparedness for owners and communities.

Monitoring Streamflow in New York

NYSDEC works with the US Geological Survey and a number of other partners to maintain a network of streamgages across the state. Streamgages are active, continuously functioning measuring devices located along waterbodies that record water elevation data that are used to determine the flow of water in the stream. Many streamgages are equipped with satellite telemetry to provide real-time data through the USGS website (see "Offsite Links" at the right).

USGU streamgage during high flow event

The NYSDEC Division of Water uses streamflow data to conduct a number of programs and activities. These include the operation of NYSDEC-operated flood control facilities, maintaining flood forecasting and drought warning capabilities, and supporting water quantity and water quality management programs. The network also supports a Stream Estimation Tool, that uses long period-of-record streamflow information in conjunction with data from current gages to provide statistical estimates of flows in ungaged streams. Though obviously not as precise as actual streamgage data, these estimates are sufficient for most other NYSDEC water quality management programs.

USGS streamgages are managed and operated to rigorous national standards. Because of this, it's not practice nor cost effective to have a USGS streamgage operating on every stream. Therefore, NYSDEC has identified those locations that that support its most critical programs as "highest" and "high" priority. These include gages used in the flood protection and drought warning programs, as well as those gages that are integral to maintaining the Stream Estimation Tool. An outline of the Streamgage Network (PDF) (115 KB) lists the currently operating streamgages on New York waters, along with the priority of that gage as assigned by NYSDEC, and the organization currently providing funding toward USGS operation of the gage. The outline also shows some gages that have been recently discontinued, and others where continued funding of the gage is threatened.

Additional information regarding streamgages can be found on the USGS website (USGS links can be found at the right, under "Offsite Links").