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Construction, Reconstruction or Repair of Dams and other Impounding Structures

Regulated Activities

A Protection Of Waters Permit is required for:

Constructing, reconstructing, repairing, or modifying dams and water impounding structures that permanently or temporarily impound water as a result of a structure placed across a watercourse or overland drainage way or which receive water from an external source such as drainage diversion or pumping of ground water.

Some examples of activities requiring this permit are:

  • siting and constructing a new dam or water impounding structure (i.e., concrete, earthen, stone and wooden structures);
  • reconstruction or modification (i.e., refacing, anchoring, breaching, or removal of an existing structure);
  • repairs or maintenance which may affect the structural integrity or functional capability of a dam or impounding structure.

Exempt Activities

The most common impoundment related activities not needing a Protection of Waters
Permit for a Dam or Other Impoundment Structure are constructing or repairing a dam or structure used for impounding water that satisfies any one of the following criteria:

  • maximum height is 6 feet or less (maximum height is measured as the height from the downstream (outside) toe of the dam at its lowest point to the highest point at the top of the dam);
  • maximum impounding capacity is one million gallons or less (maximum impounding capacity is measured as the volume of water impounded when the water level is at the top of the dam);
  • maximum height is between 6 feet and 15 feet and the maximum impounding capacity is less than 3 million gallons.

Note: The exempt activities listed only represent exemptions for this section of the Protection of Waters Program. Other DEC permits under other sections of the Protection of Waters Permit Program or under other Articles of the Environmental Conservation Law may be required.

Is Your Project Minor or Major?

Review time frames, procedures and requirements for public notice for applications are different for Minor and Major projects under the Uniform Procedures Act requirements (6NYCRR Part 621). Generally, Minor projects have shorter review time frames and require less public review.

The only Minor Dam and Water Impoundment Structure projects are those confined to repairing existing structures contained in DEC's inventory of dams. (Contact DEC Dam Safety Section at 625 Broadway, 4th Floor, Albany, NY 12233-3507, phone (518) 402-8185 to determine if a structure is included in the dam inventory.)

All other activities are considered Major Dam projects for purposes of review and public notice as required by the Uniform Procedures Act. For additional information, see our web page Getting an Environmental Permit.


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  • NYS DEC
    Division of Environmental Permits
    4th Floor
    625 Broadway
    Albany, NY 12233-1750
    518-402-9167
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