Nutrient Erosion Study Begins at California’s Clear Lake

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Clear Lake, the largest natural lake entirely within California, has a severe problem with harmful algal blooms which can be detrimental to aquatic life by depriving it of oxygen when the algae dies, sinks, and decays. A driving factor of these conditions are the nutrient loads being carried into the lake by soil erosion and the transport of sediment from the lake’s tributaries. 

Mount Konocti on the western shore of Clear Lake, California

Aerial view of the western shore of Clear Lake, California.

One area of concern is the South Cow Mountain Off-Highway Vehicle (OHV) Management Area, in the headwaters of Scotts Creek, which flows into Clear Lake. To address this concern, USGS scientists will make a baseline assessment of Scotts Creek and its tributaries to know where erosion is occurring. Results from this research will help the federal Bureau of Land Management (BLM) evaluate the cause(s) of the erosion and how erosion contributes nutrient loads going into Clear Lake. In addition, the results will be used by the BLM to establish a long-term monitoring program to demonstrate possible reductions in the nutrient loads coming from Scotts Creek once erosion control measures have been implemented.

Work on this project began in late 2020 and will continue until the summer of 2025.

Learn more about this project >

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Date published: June 9, 2020
Status: Active

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