Strawberry Creek Watershed Restoration
Location: Redwood Creek, Orick, California
Clients and Partners: Pacific Coast Fish, Wildlife, and Wetlands Restoration Association and Redwood National Park
Strawberry Creek is located within the northwestern portion of Humboldt County, California and is a tributary to the Redwood Creek estuary. The Redwood Creek basin, including Strawberry Creek, is identified as a specific hydrologic unit in coho recovery plans. Strawberry Creek historically supported coho, steelhead and a large sea-run cutthroat trout population and has the potential to play a significant role in recovering salmonid populations within the larger Redwood Creek basin.
Michael Love & Associates (MLA) lead the planning and participated in the implementation of a multi-step, multi-organization restoration effort for 9,000 feet of Strawberry Creek that encompasses both public and private lands. Implementation has been ongoing since 2007. Project planning and implementation has focused on identifying and addressing the physical and vegetative constraints that compromise fisheries habitat and geomorphic function of the stream. These constraints include undersized and perched culvert crossings, excessive sedimentation in the stream, decreased riparian area, grazing impacts, and the spread of invasive Glyceria and reed canary grass (Phalaris arundinacea), which physically block fish passage, degrade water quality, and prevent native riparian growth. The undersized crossings and the presence of the invasive grasses in the channel also cause chronic out-of-bank flooding of adjacent ranchlands, limiting productivity and threatening livestock safety.
MLA conducted an initial planning study that entailed a reconnaissance level evaluation of limiting factors throughout the entire 9,000-foot reach of stream channel. Restoration site prioritization was based on first implementing work that would improve channel capacity and reduce water levels sufficiently to re-establish riparian areas that will ultimately out-compete the invasive grasses. These included physical removal of invasive grasses, riparian area re-establishment, and stream crossing upgrades. Other improvements recommended included livestock exclusion fencing, upslope sediment reduction, and channel and wetland restoration.
MLA prepared final plans for improvements on Redwood National Park property that include restoration for 1,200 feet of wood-forced step pool and wetland slough channels, and construction of 500 feet of backwatered side channels to create off-channel rearing areas for juvenile salmonids. The project also included reed canary grass control by grubbing and construction of planting mounds adjacent to the channels to help control invasive grasses and to recreate what was historically a hummocky spruce-alder forested wetland. Construction of this portion of the project occurred in 2014.
Additionally, MLA prepared design plans to replace an undersized and perched concrete box culvert that was identified as a fish passage barrier. The crossing replacement consists of a 47-foot free spanning bridge and restoration of the natural channel through the crossing. The design of the bridge involved detailed hydraulic modeling to evaluate potential impacts to a FEMA floodplain.
Funding for the project was provided by California Department of Fish and Wildlife, California Wildlife Conservation Board, Redwood National Park, American Rivers through the NOAA Restoration Center, and the U.S. Fish and Wildlife Service.