Ecological indicators of water quality in the Spokane River, Idaho and Washington, 1998 and 1999

A water-quality investigation of the Spokane River was completed during summer low-flow conditions in 1998 and 1999 as part of the USGS NAWQA Program, in cooperation with the WDOE. (Abbreviations used in this report are defined on the last page.) Samples for analyses of water chemistry; bed sediment; aquatic communities (fish, macroinvertebrates, and algae); contaminants in tissue (fish and macroinvertebrates); and associated measures of habitat were collected at six sites downstream from Coeur d’Alene Lake between river miles 63 and 100. These data provided baseline information to evaluate the water-quality status of the Spokane River and can be used to determine the ecological risk to aquatic organisms from contaminants.