next up previous contents
Next: Agricultural Water Use Up: Groundwater Previous: Groundwater   Contents

Problem: Groundwater Overdraft

According to the United States Geological Survey, significant ground-water depletions have occurred in the High Plains aquifer of the Midwest, many areas in the Southwest (AZ, CA, NM, NV, and TX), the Sparta aquifer in the Southeast (AR, LA, and MS), and in the Chicago-Milwaukee area. Studies estimate that current groundwater overdrafts in Arizona total 2.5 million acre-feet per year, approximately 50% in excess of maximum sustainable yield (Carter et al., 2000). A Kansas Geological Survey study projects that significant regions of that state will have exhausted their groundwater supplies by 2025 (Buddemeier et al., 2000). In some areas of Nebraska, groundwater levels have fallen almost 30 feet below normal (Kranz et al., 1993). The saturated thickness of the High Plains Aquifer has declined by over 50 percent in some areas. A bill seeking to establish the High Plains Groundwater Resource Conservation Act, introduced into the 107th Congress, listed aquifer level declines of over 100 feet between 1950 and 1997 as justification for legislative action (Congress, 2001).



Andy Wingo 2001-12-10