Stream restoration

Ecological stream restoration is the return of a stream ecosystem’s structure and function to a state that is more reflective of its predisturbance form. Ecological engineering principles, which focus on ecosystem self-design and self-organization, are often used in stream restoration projects because of its ecologically based procedures and goals. Regardless of the method applied, the goal of ecological stream restoration is to restore the stream ecosystem’s physical, chemical, and biological composition as close as possible to the native state given the permanent watershed alterations. Restoring a stream’s physical and biotic dynamic patterns leads to ecosystem structure and function (e.g., energy flow, nutrient cycling, and community resilience) that more closely approximates the natural condition. Stream restoration has many challenges including varying sources of pollution and high ecological variability associated with stream size and geographic region. Ecological stream restoration depends upon understanding the physical, chemical, and biological constraints on developing stream communities and ecosystems. Understanding how stream organisms respond to their environment (i.e., the ecology of the stream) is vital to constructing and implementing a successful restoration project.