Water-level changes in wells along the west side of the Cedar Creek anticline, southeastern Montana

Water levels have been measured periodically in wells along the west side of the Cedar Creek anticline in southeastern Montana since 1962-64. The measurements show the response of the Fox Hills-Hell Creek aquifer of Late Cretaceous age to withdrawals for domestic, stock, and industrial uses. Water levels were as much as 109 feet lower in 1975 than they were in 1962-64. During the same period water levels lowered by 10 feet under about 400 square miles. From 1962-64 to 1969 water levels declined by as much as 133 feet. From 1969 to 1975 water levels rose as much as 46 feet near the outcrop of the aquifer and lowered 10 feet or more beneath about 100 square miles. Decreases in the rate of pumping from industrial wells near the outcrop have caused the water-level rise. Withdrawals from domestic and stock wells have remained the same or increased during the last 14 years and have contributed to water-level declines in areas west of the aquifer 's outcrop. (Woodard-USGS)