KRIS Web Background Pages: Stream Clearance
Stream clearance was one of the first phases of "restoration" on coastal rivers in Mendocino County beginning in the late 1950s. The idea was to re-establish fish passage around large wood jams that formed after logging activities. Holman and Evans (1964) documented large wood removal on the Noyo River and stated that a secondary purpose of the activity was to allow sediment to flush from upstream of log jams where good spawning gravels were buried under fine sediment. Big River also had extensive large wood removal which was documented by Jackson Demonstration State Forest. Large wood removal in the basin began in the 1950s and continued through the 1990s. Large wood was also scoured by previous splash damming and log drives which took place in the Big River basin from 1880 to 1940 (see History).
There are numerous memos by the Center for Education and Manpower Resources all describing stream conditions and the need for large wood removal. The Jackson Demonstration State Forest record of large wood removal likely documents some of the follow up work projects.
|The image at left shows where large wood was removed as part of stream clearance projects in the North Fork of Big River, including the Chamberlain and James Creek tributaries. Large wood was thought to impede fish passage but its value in adding to complexity of fish habitat was overlooked. Data provided by the Jackson Demonstration State Forest.|
|The log jam on Johnson Creek depicted at left was causing nearby stream bank erosion and was also thought to be a potential impediment to fish migration. The gravel in the foreground is typical of aggraded reaches above log jams. This sediment storage was formerly viewed as "burying spawning gravels." In fact, this type storage helps stagger impacts of sediment to various stream reaches. July 1989.|
|After large wood was removed, the channel is clear of debris and makes fish passage upstream easier. However, the resulting habitat is flat and monotypic. Sediment released by these activities had ripple impacts on spawning gravels downstream. The large wood had been helping to create habitat diversity by scouring the stream and creating pools. July 1989.|
Center for Education and Manpower Resources (CEMR). 1979. East Branch North Fork Big River (North Fork Big River tributary) stream survey, 26 March 1979. CEMR unpublished file memo by A. Newby. Yountville, CA. 3 pp.
Center for Education and Manpower Resources (CEMR). 1979a. Little North Fork Big River (North Fork Big River tributary) stream survey, 2 April 1979. CEMR unpublished file memo by A. Newby. Yountville, CA. 4 pp.
Center for Education and Manpower Resources (CEMR). 1979b. Railroad Gulch (Big River tributary) stream survey, 28 March 1979. CEMR unpublished file memo by A. Newby. Yountville, CA. 2 pp.
Center for Education and Manpower Resources (CEMR). 1979c. Thompson Gulch (Little North Fork Big River tributary) stream survey, 2 April 1979. CEMR unpublished file memo by A. Newbury. Yountville, CA. 3 pp.
Holman, G. and W. Evans. 1964. Noyo River Stream Clearance Projects. California Department of Fish and Game. 12 p.