The field of hydrogeology (hydro- meaning water, and -geology meaning the study of the earth) is the area of geology that deals with the distribution and movement of groundwater in the subsurface. Groundwater can be an abstract idea to folks because it is occurs below ground and cannot be directly observed.

Anyone who has driven across Iowa knows that the state is dominated by agriculture. But among the fields lined with corn, soybean, and livestock, a new feature is becoming more common: wetlands.

Evidence of how Iowa has evolved over Earth’s 4.6-billion-year history is preserved in the rocks. The job of an IGS geologist is to study these rocks using a variety of tools and methods and from the data collected continue to reveal and refine our understanding of that history.

The IGS monitors groundwater levels in 48 wells scattered across Iowa that are completed in most of the major bedrock aquifers. These wells provide a historical record of groundwater levels and help evaluate aquifer sustainability.

Since 2019, the Iowa Geological Survey led by Matthew Streeter has been quantifying reductions in nitrate, phosphorus, and sediment concentrations at multiple sites in Keokuk, Scott, and Wapello counties in Iowa.