DWR_2873798 - Laserfiche WebLink

DISCUSSION During the winter of 2006-07, water levels were obtained for approximately 650 wells in the Northern High Plains Designated Ground Water Basin. An attempt was made to measure all the wells within an eight-week period beginning in mid-December 2006; however, major accumulations of snow starting towards the end of December made it impossible to complete the measurement program before mid-April. Throughout the Northern High Plains, the water levels continue to show the regional decline that is to be expected when water is being "mined." Overall, slight improvements in water levels were seen in the W -Y Ground Water Management District, and in Washington, Kiowa and Prowers County monitoring wells. The well hydrographs contained in the report show water level trends throughout the basin. The average rate of decline during over the past year was -1.13 feet. This represents removal of approximately 1,017,000 acre-feet from storage. A decline of one foot is equal to a depletion from storage of approximately 900,000 acre-feet. Over the past five years (2002 to 2007), the basin -wide water level has declined an average of approximately 6.26 feet, representing a depletion of approximately 5,634,000 acre-feet or more than five percent of the estimated 1965 storage in the aquifer. The depletion for the past ten years (1997 to 2007) indicates that more than 8,496,000 acre-feet have been removed from storage (decline of -9.44 feet). This equates to a rate of depletion of a little more than one-half percent per year. The original basin designation allowed for a depletion of 40 percent in 25 years. This was amended in 1990 to a depletion of 40 percent in 100 years. At the 10 -year average rate, the basin is being depleted at the rate of 50 percent in 100 years. This figure is somewhat misleading in that some areas in the basin are experiencing much higher rates of depletion due to a lesser saturated thickness and the fact- that 2000 to 2003 were extremely dry years.