NSF Award
2409364
This research will focus on groundwater and springs in the Driftless Area of the Upper Midwest, a topographically distinct karst region spanning four states. Extensive agriculture above ground and fast water flow through caves and other openings below ground make the region at risk for groundwater contamination, which has been an ongoing problem for decades but has recently reached a state of emergency in many communities relying on groundwater for their drinking water supply. This project aims to identify key controls of groundwater quality at springs. Springs act like windows into what is happening below ground, and are also important ecologically, culturally, and economically, making them excellent study sites. A team of college students will visit 200 or more springs across the region, recording the same set of basic information about geology, water quality, and flow rates. This data set will then be used to test hypotheses about which factors contribute to healthier springs, and will be made public. The results of this study can help guide groundwater resource stewardship in the future. Additionally, the students involved in the project will receive mentoring, technical methods training, and real-world field experiences that will help prepare them for careers in the earth sciences.<br/><br/>The research goal of this project is to test hypotheses as to the relative importance of stratigraphic position, groundwater age and provenance, springshed land use, and geographic location on spring water quality. Previous studies have either focused on recording flow rates and contaminant concentrations over time at a single point in space, or surveyed many points in space at different points in time. The temporal range makes interpretation difficult, and the spatial scope is often limited by state boundaries. This project will record patterns in space over a short window of time, enabling more meaningful analyses - students will conduct a synoptic “snapshot in time” survey of 200 springs across the region, under baseflow-dominated conditions at two points during the same hydrologic year (midwinter and late summer). For a subset of springs, tritium, stable isotope, and major ion analysis will be used to determine groundwater age and provenance. The survey will include existing and planned long-term spring monitoring sites (known as “sentinel springs”). The synoptic survey will allow sentinel springs to be understood in their broader regional context, while the sentinel springs provide a more in-depth understanding of individual sites in the survey, significantly increasing the information value of each dataset.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
