Streamflow and fluvial-sediment discharge data are being collected at selected streams and highway gutters in the Lake Tahoe basin to determine the extent of erosion from highway cuts and to evaluate the effects of various land treatment practices to reduce erosion.
Precipitation in the Lake Tahoe area during 1972 was 77 percent of normal; consequently, runoff was well below normal. Seventy-six percent of the total annual runoff during the 1972 water year occurred from March through June 1972.
Sediment samples were collected during the year at streamflow gaging stations and at gutter stations at highway cuts to define the range of transport conditions. The major part (87 percent) of the annual suspended-sediment discharge during the 1972 water year occurred during the snowmelt runoff period, March through June.