2012 Center Pivot Irrigation in Tazewell County, Illinois

2012 Center Pivot Irrigation in Tazewell County, Illinois - This map displays the center pivot irrigation systems in use in Tazewell County, Illinois during the 2012 growing season. An extensive shallow aquifer provides an abundant source of water that, because of adequate rainfall and subsequent recharge, historically has not led to any long-term reduction in water levels or depletion of the aquifer even as irrigation has significantly expanded. The Imperial Valley Water Authority is a local government entity that regulates non-agricultural high-capacity wells in parts of six townships in Tazewell County and all of Mason County. The IVWA estimated groundwater withdrawals for irrigation in Tazewell County in 2012 to be approximately 28 billion gallons, which equates to about 233 million gallons a day (MGD) across a 120-day growing season. Together, Mason and Tazewell Counties accounted for nearly 100 billion gallons of groundwater withdrawal for irrigation in 2012. 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. A total of 449 fields were identified as using center pivot systems in Tazewell County during the summer of 2012, representing 42,419 acres of farmland. USDA reported 337,376 total acres of farmland in Tazewell County, suggesting that center pivot irrigation systems are used to irrigate approximately 13 percent of all farmland in this county (2012, NASS Census). This map is available online as a 28" x 24" PDF file (4.1MB).Ope