NORTH FORK NAVARRO INSTREAM COHO HABITAT ENHANCEMENT PROJECT
In 2017, the North Fork Navarro Instream Coho Habitat Enhancement Project installed approximately 38 streamside conifers, at 10 individual sites along 1.0 mile of the North Branch North Fork Navarro River. The Project was completed using funds awarded from the State Water Resources Control Board Timber Regulation and Forest Restoration Fund and NOAA Restoration Center's Coastal and Marine Community-Based Restoration Program. This is the first phase of a two phase project in collaboration with Mendocino Redwood Company, and working with expert professionals from All in 1 Tree and Timber, Inc., and the California Conservation Corps.
The North Branch North Fork Navarro River is a tributary to the North Fork Navarro River, and is located approximately 30 miles southeast of the city of Fort Bragg in Mendocino County. The watershed is identified as continuing to support several species of anadromous salmonids, including: Oncorhynchus mykiss (steelhead trout), Oncorhynchus kisutch (coho salmon), and Oncorhynchus tshawytscha (Chinook salmon). The North Branch North Fork Navarro is identified as “core recovery habitat” in the Navarro River according to the NOAA-National Marine Fisheries Service’s Coho Recovery Plan. Large wood augmentation has been identified as a key recovery action in the state and federal recovery strategies. The Navarro River is listed on Section 303(d) of the Clean Water Act as impaired due to excess sediment and elevated temperatures.
Large wood is known to create habitat complexity and enhance valuable habitat for both coho salmon and steelhead trout. Additionally, LWM assists in the transportation and sorting of excess sediment and, most importantly, pool formation associated with bed scour. The Project used the accelerated, or rapid, recruitment method. The basic principle of the method is to mimic the natural process of tree fall to create habitat. It includes the directional falling of riparian trees directly into or near the stream channel. Trees that are introduced are either unanchored, or use non-traditional anchoring methods. When available, trees are directionally felled into fixed positions where they can be wedged between or among other standing trees or fixed objects. These “fixed logs” are installed to provide a collection point for additional project wood or existing watershed materials. Some trees will be installed as “transport logs” for the purpose of moving downstream through the system and collect elsewhere.