The Cache la Poudre River, Colorado, as a drinking-water source

Abstract

Printed on recycled paper F rom October 2002 through September 2003, the U.S. Geological Survey conducted a study to assess the quality of a subset of the Nation’s drinking-water supplies. In the South Platte River Basin of Colorado, the Cache la Poudre River, one of two surface-water sources of drinking water for the city of Fort Collins, Colo., was included in the study. The study focused primarily on the presence or absence of organic chemicals in source water. The 271 compounds studied included dissolved organic carbon, 89 volatile organic compounds, 123 pesticide compounds, and 59 wastewater compounds. Escherichia coli (E. coli) bacteria also was collected. Of the 271 compounds monitored, 257 were not detected. Low concentrations of dissolved organic carbon and E. coli bacteria were detected throughout most of the study period. In addition, 3 volatile organic compounds, 1 pesticide, and 10 wastewater compounds were detected in the Cache la Poudre River. All concentrations detected were below established water-quality standards. Most of the compounds detected appeared to be related to recreation, automobile emissions, or personal and household use of chemicals in the drainage area. Based on the results of this study, the Cache la Poudre River appears to provide a highquality source of drinking water for the city of Fort Collins.