Mason County has the most irrigated acreage in the state, nearly double that of any other Illinois county. Sandy soils and annual precipitation of about 38 inches promote significant groundwater recharge. An extensive shallow aquifer provides an abundant source of water that, historically, has not led to any long-term lowering of water levels or depletion of the aquifer even as irrigation has significantly expanded. The Imperial Valley Water Authority, a local government entity that regulates non-agricultural high capacity wells in Mason County and four townships in Tazewell County, estimated groundwater withdrawals for irrigation in Mason County in 2012 to be a little over 70 billion gallons, which equates to 587 million gallons a day (MGD) across a 120-day growing season. This map displays the center pivot irrigation systems in use in Mason County, Illinois during the 2012 growing season. Center pivot irrigation imprints identifiable circular patterns on the landscape which can be visible in aerial images. The USDA collects aerial imagery (National Agricultural Imagery Program) and makes them available through the USDA Geospatial Data Gateway. The NAIP images were examined for circular irrigation patterns, and field boundaries were digitized using ArcGIS version 10.0 to create a map layer. In total, 1553 fields were identified as using center pivot systems in Mason County during the summer of 2012, representing 135,684 acres of farmland and approximately 50 percent of all farmland in Mason County. This map is available online as a 34" x 22" PDF file (6.1MB).
|Original language||English (US)|
|Publisher||Illinois State Water Survey|
|State||Published - 2014|