Eight Mile Valley Project

The Eightmile Valley Sediment Reduction and Habitat Enhancement Project is in the Upper Scotts Creek Watershed within the Bureau of Land Management’s South Cow Mountain Off-Highway Vehicle Recreation Area approximately 9 miles west of Lakeport. The 16-acre valley is characterized by grasslands and riparian habitat. Its wetlands were converted to agriculture lands in the early 1900s, causing stream degradation and allowing sediment to flow into Clear Lake. 

In 2005, an attempt was made to correct stream erosion in the valley, but the control structures were washed out by the 250-year storm events of 2005-2006. In 2012, a collaborative partnership among the Scotts Valley Band of Pomo Indians, Bureau of Land Management and the West Lake Resource Conservation District (now Lake County RCD) developed a design plan and applied for and was awarded funding from the California State Water Resources Control Board.

The Scott’s Valley Band of Pomo Indians provided staff, water quality monitoring equipment and water quality monitoring for the project. The Bureau of Land Management provided fiscal sponsorship, staff, reporting and invoicing, and construction oversight of the project. The Lake County RCD provided project management and technical support. 

The design plan aimed to reduce sediment transport into Clear Lake, stabilize and restore channel geomorphology, and enhance/restore habitat value to the degraded meadow/riparian ecosystem. This was largely accomplished through realignment and stabilization of existing stream channels, stream bank stabilization with bio-control plantings, revegetation, and erosion control management practices.

Before Stream Erosion Correction
After Stream Erosion Correction

Pre-construction nesting Bird Surveys and Protective Measures for the Eight Mile Valley Sediment Reduction and Habitat Enhancement Project

Final Report for the Eightmile Valley Sediment Reduction And Habitat Enhancement Project

March 2021