Water-quality data for the American River basin, California, February-October 1979

Abstract

Data were collected in the American River basin from February to October 1979 for use in assessing the water quality in the basin. The basin covers 2,163 square miles of the western slope of the central Sierra Nevada. Basin headwaters are located primarily between Donner Summit and Carson Pass. Water-quality data were collected at 14 stream sites and at 3 sites on Folsom Lake and include selected measurements and analyses for physical, chemical, and biological properties and constituents. Water samples analyzed for dissolved constituents were filtered through a 0.45-ym membrane filter. Nutrient samples were preserved by chilling 0°C to 4°C. Trace-element samples were placed in acid-rinsed polyethylene bottles and acidified with nitric acid to a pH less than 2. Chemical determinations were made at the U.S. Geological Survey Central Laboratory in Arvada, Colo. Onsite measurements of pH and specific conductance were made by using portable meters. Temperature was measured with a handheld thermometer. Dissolved-oxygen concentration was determined by the azide modification of the Winkler method, and alkalinity by electrometric titration method. These methods are described by Skougstad and others (1979). Water discharge was determined by direct measurement, using the methods described by Buchanan and Somers (1969), or from records from nearby gaging sites. Lake samples were taken at selected depths or composited for selected depth intervals with a 4-liter Van Dorn-type sampler. Vertical-profile measurements of temperature, dissolved oxygen, specific conductance, and pH were made with a Martek Mark VI Water Quality Analyzer during each visit to the lake site. Water transparency was measured by a Secchi disk (Reid, 1961, p. 100). In addition, light penetration was measured with a Montedoro-Whitney Model LMT-8B submarine photometer. Light transmission was measured with a Martek Model XMS IN SITU Transmissometer, with a *4-m path-length sensor.

Water-quality assessment of the American River, California

“…6) in the American River basin by several State and Federal agencies and universities, but comprehensive water-quality studies of a year or more are few, and water-quality trend studies have never been done. Data collected by the Geological Survey, in cooperation with the California Department of Water Resources, between February and October 1979, and the collection and analysis methods used, are reported by Shay (1982). Data were collected basinwide at 14 stream sites and at 3 sites on Folsom Lake.…”