Quality of water of the Colorado River in 1928-1930

This report gives the results obtained in the continuation of a study of the Colorado River begun in 1925.1 The analyses represent composites of daily samples collected by the observers at the gaging stations on the Colorado River at Cisco, Utah, and Lees Ferry and Grand Canyon, Ariz.; on the Green River at Green River, Utah; and on the San Juan River near Bluff, Utah. Analyses are given for samples collected about once a month from the Williams River at Planet, Ariz. The Arizona stations are operated under the direction of W. E. Dickinson, district engineer of the Geological Survey at Tucson, Ariz., and the Utah stations under the direction of A. B. Purton, district engineer of the Geological Survey at Salt Lake City, Utah. The average discharges given in Table 3 were calculated from data furnished by these district engineers. Complete discharge . data for this period will be published in the regular series of water-supply papers.