Small/Low-Impact Hydropower Projects - Do I need a preliminary FERC dam safety review?

Before projects are constructed, Commission staff review and approve the designs, plans, and specifications of dams, powerhouses, and other structures. During construction, Commission engineers frequently inspect a project, and once construction is complete, Commission engineers continue to inspect it on a regular basis.

Small/low impact hydropower projects should be located at sites where there will be few environmental impacts from the project. Some factors for a project site to be considered low impact include:

• Located at existing dams or conduits.
• Located on lands owned by the licensee/exemptee.
• Cause little change to water flow and use.
• Have no impacts on threatened or endangered species or fish passage.

Projects having these characteristics will most likely be located at low hazard potential dams. Low hazard dams are low in economic and/or environmental losses and failure or misoperation of these types of dams would not result in loss of human life. The Commission's dam safety, public safety, and security requirements are minimal for low hazard potential structures and should not cause projects to become infeasible.

The Commission's dam safety guidelines become more of a factor if a project uses a significant or high hazard potential dam (i.e. failure or misoperation will probably result in loss of human life). Developers should consider the following items when considering a small/low impact project at a significant or high hazard potential dam:

• If the project utilizes a federal dam, the licensee/exemptee is only responsible for the project features associated with generating electricity - not the dam.
• Just because a dam is classified as having a significant or high hazard potential does not mean the project will be uneconomical. An incremental hazard evaluation should first be performed to determine the project's inflow design flood (IDF). After the IDF is known, it will become clear what costs are associated with bringing the project into accordance with the Commission's guidelines.
• Significant and high hazard potential dams are typically larger structures than low hazard potential dams. The additional generation that can be gained from utilizing a larger structure could justify the investment needed to bring the project into accordance with the Commission's guidelines.
• The additional oversight associated with Commission-regulated significant and high hazard dams should result in potential problems being discovered before they lead to bigger and more expensive problems.

For details regarding the Commission's Dam Safety Program and small/low impact hydropower development, see: Dam Safety and Inspections and The Role of the FERC's Dam Safety Program with Small/Low Impact Hydropower Development