Figure A

Protection, Mitigation, And Enhancement

Protection, mitigation, and enhancement are three broad and different strategies that can be used to minimize possibly adverse environmental effects from a hydroelectric project.

Protection

Protection strategies focus on preserving areas in a watershed that are ecologically important, healthy and intact. Doing so often means protecting areas from human activities that can disturb the ecological functions of aquatic and riparian habitats.

For instance, wetlands provide critical wildlife habitat, assist with water purification, and help store water during storms and floods. Because wetland areas may be in decline, assisting with their protection may be part of a hydroelectric project owner's efforts to assist with maintaining the overall health of a given watershed. A watershed is the geographic area that drains into a common river, river system, or other body of water.

Mitigation

In situations where habitat conditions are seriously degraded and impacts are unavoidable and can not be recovered, mitigation strategies may be employed to help offset these losses.

For instance, the abundance and diversity of fish species may decline because fewer fish can successfully migrate past one or more dams to reach their spawning areas. In this instance, a mitigation strategy might include building a hatchery.

Enhancement

When a change to the environment occurs, one means of addressing the new effects is to establish enhancements that minimize or alleviate these effects. Such enhancements use technology and/or natural materials to alter or modify habitat conditions. By so doing, nondesirable habitat conditions can be offset to the greatest extent possible.

Examples of enhancements include creating fish passage, use of vegetation to stabilize streambanks, or changing water flow conditions to meet the habitat needs of particular species.