Reconnaissance assessment of erosion and sedimentation in the Canada de los Alamos Basin, Los Angeles and Ventura counties, California

J. M. Knott

doi:10.3133/ofr78873

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Reconnaissance assessment of erosion and sedimentation in the Canada de los Alamos Basin, Los Angeles and Ventura counties, California

J. M. Knott

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Abstract

An assessment of present erosion and sedimentation conditions in the Canada de Los Alamos basin, Calif., was made to aid in estimating the impact of off-road-vehicle use on the sediment yield of the basin. Evaluations were made by reconnaissance techniques and by comparing the study area with other off-road-vehicle sites in California. Major-storm sediment yields for the basin were estimated, using empirical equations developed for the Transverse Ranges and measurements of gully erosion in a representative off-road vehicle basin. Normal major-storm yields of 73,200 cubic yards would have to be increased to about 98,000 cubic yards to account for the existing level of accelerated erosion caused by off-road vehicles. Long-term sediment yield of the Canada de Los Alamos basin upstream from its confluence with Gorman Creek, under present conditions of off-road-vehicle use, is approximately 420 cubic yards per square mile per year--a rate that is considerably lower than a previous estimate of 1,270 cubic yards per square mile per year for the total catchment area above Pyramid Lake. (Woodard-USGS)

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J. M. Knott. 1978. Reconnaissance assessment of erosion and sedimentation in the Canada de los Alamos Basin, Los Angeles and Ventura counties, California. https://doi.org/10.3133/ofr78873

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