Incised Stream Restoration in the Western U.S.

Incised stream

An incised stream occurs when a stream cuts its channel into the bed of a valley through degradation (erosion). As a stream cuts its channel, the water table drops and the surrounding vegetation changes from wetlands and meadows to dry shrublands. Incised streams are thought to be a result of the removal of beaver from arid landscapes in the western United States.

The beaver is considered a keystone species because their presence on the landscape allows other organisms to exist that otherwise would not. This is because beaver impoundments and dams change the spatial distribution of water as well as water flow rate. Through the creation of ponds and wetlands, beavers can increase plant and animal biodiversity. The restoration of streams from beaver or simulated beaver dams allows short-term streams to become perennial or long-term flowing streams.

*Please note that the appearance of this page was changed in November 2020, but all of the original information was retained.

Restoring Incised Streams
If you are interested in using beavers or beaver mimicry to restore incised streams or increase water retention, then review the collection of information for managers and landowners below.

This StoryMap Going With the Flow provides a summary of five case studies from across the West that use beaver-related restoration practices.