Have Nitrate Concentrations Changed in Water in the Alluvial Aquifer of the UpperBlack Squirrel Creek Basin since 1984

摘要

The alluvial aquifer of the upper Black Squirrel Creek Basin, about 25 miles eastof Colorado Springs, supplies most of the water for irrigation and domestic use in the basin and, since 1964, supplies water for export to the Colorado Springs area. The U.S. Geological Survey, in cooperation with the Cherokee Metropolitan District (CMD), collected samples form 36 wells in the upper Black Squirrel Creek alluvial aquifer in August 1984 to determine the distribution of concentrations of nitrite plus nitrate as nitrogen (referred to as nitrate). Twenty-eight of the 36 wells samples in August 1984 were resampled in Auguest 1996 to determine whether nitrate concentrations in the alluvial aquifer changed since 1984. This fact sheet discusses change in nitrate concentrations in the upper Black Squirrel Creek alluvial aquifer between 1984 and 1996, where those changes occurred, and possible casues for the changes in nitrate concentrations.