EFFECTS OF TOPOGRAPHY AND SOIL PROPERTIES ON RECHARGE AT TWO SITES IN AN AGRICULTURAL FIELD

• Published in: Journal of the American Water Resources Association 2000-12, Vol.36 (6), p.1401-1416
• Main Authors: Delin, Geoffrey N., Healy, Richard W., Landon, Matthew K., Böhlke, John Karl
• Format: Article
• Language: English
• Subjects: chlorofluorocarbon age dating; Earth sciences; Earth, ocean, space; Exact sciences and technology; focused recharge; ground water; Hydrogeology; hydrograph analysis; Hydrology. Hydrogeology; USA, Minnesota
• ISSN: 1093-474X; 1752-1688
• DOI: 10.1111/j.1752-1688.2000.tb05735.x

Estimates of groundwater recharge were made at two sites within an agricultural field near Princeton, MN, that was cropped during the growing season in field corn. The sites were located in an upland and a lowland area of an undulating glacial outwash sand deposit. Dye tracer tests were conducted, and information was collected on soil properties. Well hydrograph analysis, chlorofluorocarbon age dating, and unsaturated-zone water balance were employed to examine any differences in estimated groundwater recharge rates. Recharge was estimated to range 10 40% of natural precipitation. Average annual recharge at the lowland site exceeded that at the upland site by approximately 30% based on hydrograph analysis, by 80% based on chlorofluorocarbon dating, and by 60% based on the unsaturated-zone water-balance method. This increased recharge at the lowland site was attributed to surface run-on of water, lamellae found below the upland site that were not found at the lowland site, and coarser-grained sediments at the lowland site.