Stream Restoration

Streams in North America bear hidden scars of degradation. What may look like an idyllic stream is often prone to flooding, drought, and erosion. One of the key causes of this is the historic extirpation of beavers.

North American Beavers once occupied nearly all streams in North America, but intense trapping in the 19th and early 20th centuries reduced their population by as much as 98 percent. Without beavers building dams, the way these streams and their surrounding wetlands function deteriorated dramatically.

Recently, hydrologists and managers have begun to realize that mimicking beaver dams and natural log dams provides transformative benefits for restreams, giving rise to a practice called low-tech, process-based restoration. By using simple tools and locally available materials, land managers across North America are beginning to heal the wounds of beaver extirpation and stream degradation.