Rice County, Minnesota: drinking water report. Rice County in southern Minnesota has about 67,000 residents, with Faribault and Northfield as the main…
Rice County in southern Minnesota has about 67,000 residents, with Faribault and Northfield as the main communities. Groundwater from glacial drift and bedrock aquifers provides nearly all drinking water. The county's agricultural economy – dairy, corn, and soybeans – operates on soils that range from heavy clay till to sandy outwash, creating variable groundwater vulnerability across short distances.
The sandy outwash areas in western Rice County are particularly vulnerable to nitrate contamination. According to the Minnesota Department of Agriculture's 2024 groundwater monitoring report, nitrate concentrations in the surficial aquifer beneath these sandy zones averaged 8.3 mg/L, with 24% of sampled wells exceeding the MCL of 10 mg/L. The clay till areas in the eastern part of the county show much lower contamination.
A 2024 MDH investigation found PFAS at 5 ppt in one public water system in Faribault, likely from diffuse sources rather than a single point of contamination. Naturally occurring manganese in the bedrock aquifer is another concern – several wells in the county exceed the health advisory level of 300 ppb.
Water quality in Rice County depends heavily on your geology. If you are in a sandy outwash area, your well is more exposed to surface contamination. The Minnesota Geological Survey's well atlas can help you understand what lies beneath your property.
Check your water for available data. For nitrate and manganese, reverse osmosis handles both effectively. Our water filter guide covers well water systems suited to Minnesota conditions. Get your detailed report for local data, and visit our Minnesota page for statewide patterns.