Dry Creek Habitat Enhancement Feasibility & Alternatives Analysis, & Detailed Design

Dry Creek Habitat Enhancement Feasibility & Alternatives Analysis, & Detailed Design 2017-05-05T04:28:26+00:00

Project Description

Dry Creek has been managed intensively for forestry, agriculture and gravel mining since the 1850s, resulting in 25 feet of channel incision. Since the mid-1980s, Dry Creek has also been highly regulated for flood control and water supply. The terms of the effective biological opinion for flood control and water supply operations in the Russian River system include substantial habitat enhancement in Dry Creek, with a target for enhancement of 6 miles of habitat in a 14-mile study reach. The habitat enhancement is focused towards ESA-listed coho salmon and steelhead trout. Since 2007, our work has included:

  • Feasibility and alternatives analysis study along a 14-mile reach.
  • Survey, habitat unit inventory, hydrologic analysis and hydraulic modeling, feasibility and alternatives analysis, project identification and prioritization.
  • Designed and constructed the Dry Creek Demonstration Project, which included habitat enhancements over a 1.1-mile reach (constructed 2012-2014).
  • Initiated design of an additional mile of projects which began construction in 2016 and are expected to be completed in 2018.
  • Begun design of a third mile of enhancement work be constructed starting in 2018.
  • Development of illustrative handbooks used to communicate designs with the community.
  • Extensive collaboration with stakeholders, resource agencies, and community and the US Army Corps of Engineers.

Dry Creek Valley is a renowned wine producing region in northern Sonoma County, California where more than 150 winegrowers and 60 wineries are located. (Photo Sonoma County Watershed Agency)

Detailed habitat and geomorphic field assessment helped develop our understanding of current conditions in Dry Creek.

Bank failures resulting from 20 ft+ of channel incision threaten infrastructure and contribute fine sediment.  Photo: before construction.

Project elements include bioengineered bank stabilization, constructed backwaters and side channels, installation of boulders and log jams, and riparian restoration.

Our bioengineered solution involves intensive revegetation to improve riparian ecology and future bank stability in addition to large wood that provides fish habitat in the channel.

Constructed off-channel habitat provides critical summer and winter habitat for ESA-listed coho and steelhead. (before)

As riparian vegetation matures, the project realizes additional aquatic and terrestrial habitat benefits.

Working with the Sonoma County Watershed Agency, we developed a handbook to communicate designs to adjacent landowners.

Intensive monitoring of the completed project has shown robust fish use in the constructed habitats.