BLM Alder Creek Headcut Meadow Restoration
The Alder Creek Headcut Restoration Project is located approximately 6.5 miles NE of Crane Oregon on the lower end of a 40 acre wet meadow on Alder Creek, approximately 6.5 miles north of its confluence with Crane Creek.
The wet meadow appears to have been the result of beaver activity along the valley. The soil strata indicates centuries of fluvial sediment that dropped out of suspension as the beaver dams slowed the water flow. This fluvial sediment was very susceptive to hydraulic movement. Recent events, possibly declining beaver populations, have weakened the dam network and Alder Creek is down cutting through the accumulated sediment. If left unchecked, it was likely the down cutting would move upstream, widening and deepening, as storm runoff re-suspends the fluvial material and relocate it downstream through the system. The groundwater table was declining with the down cutting of the channel which resulted in the wet meadow becoming dry and further reducing the vegetative habitat and therefore the likelihood of beaver recovery in this area.
The project recreated the conditions which created the wet valley. A rock and earthen check structure was installed at the lowest apparent beaver dam site (headcut #1). Fish passage was provided over this check structure via a pool and roughened channel system. A long pool was created above the check structure in the incised channel. A series of large woody debris structures were placed along the incised channel to trap sediment and debris and begin the natural process of replacing sediment removed by the headcutting. In the interim, the woody debris structures will provide habitat for aquatic life in the pools providing shade and safety from predators. Live willows and alders were harvested from the existing plant material and planted along the incised channel to provide shade and additional cover habitat.