Free Missouri water report: PFAS & lead levels for every water system, worst-affected cities, and EPA violations. Check your ZIP.
Missouri's drinking water serves approximately 6.2 million residents across a state that sits at the confluence of two of North America's great rivers – the Missouri and the Mississippi. These rivers and their tributaries provide surface water for major communities, while groundwater from the Ozark Aquifer and alluvial aquifers along river valleys serves much of the rest of the state. The Missouri Department of Natural Resources (DNR) regulates about 2,500 public water systems. St. Louis draws from the Missouri and Mississippi rivers through separate intakes; Kansas City draws from the Missouri River. Springfield and communities across the Ozark Plateau rely on deep limestone aquifers that produce naturally clean, cold water – some of the best groundwater in the Midwest.
Missouri's water quality profile splits along geographic lines: the northern half of the state, with its agricultural prairie, faces nitrate and pesticide contamination similar to Iowa's. The southern Ozarks have cleaner groundwater but are vulnerable to contamination through the region's karst geology – limestone dissolved by water into caves, sinkholes, and underground channels that can transmit surface pollutants directly to aquifers without natural filtration.
PFAS monitoring in Missouri has identified contamination at military installations and is expanding through the UCMR5 program. Whiteman Air Force Base in Johnson County, home to the B-2 stealth bomber fleet, is the state's most prominent military PFAS site. AFFF used in firefighting training has contaminated groundwater on and around the base, with detections confirmed in monitoring wells.
Beyond Whiteman, PFAS has been detected at several Missouri airports and fire training facilities. The Missouri DNR has conducted targeted sampling at suspected sites but has not undertaken a comprehensive statewide assessment. The state has not adopted PFAS MCLs and relies on federal standards.
St. Louis's industrial legacy adds another potential contamination pathway. The city and its suburbs hosted a range of 20th-century manufacturing operations – including those supporting the nuclear weapons program – that used fluorinated compounds. The Coldwater Creek contamination site in north St. Louis County, where nuclear waste from the Manhattan Project was improperly stored and spread, is a Superfund site that illustrates the region's complex industrial contamination history. While that site is primarily a radiological concern, it reflects the broader pattern of industrial waste disposal that could include PFAS-containing materials.
Among Midwestern states, Missouri occupies a middle position on PFAS. Neighboring states with more severe contamination profiles – Michigan, Minnesota, Illinois – have been forced into more aggressive regulatory action. Kansas, to the west, has the McConnell AFB site. Arkansas and Oklahoma, to the south, have less characterized PFAS situations.
Missouri's Ozark groundwater is a genuine asset. The deep limestone aquifers beneath the Springfield Plateau and Salem Plateau produce some of the cleanest drinking water in the region, naturally filtered through hundreds of feet of rock. However, the same karst geology that creates this clean deep water also creates surface vulnerability: sinkholes, losing streams, and cave systems can channel surface contamination directly underground. The Missouri Geological Survey has mapped over 7,000 caves and 30,000 sinkholes in the state, and research has shown that contaminants introduced at the surface can reach springs and wells within hours.
St. Louis's river-sourced water faces the same challenges as other major river cities: upstream contamination from agricultural and industrial sources across the entire watershed, seasonal variations in source water quality, and the formation of disinfection byproducts when treating organic-rich river water.
Missouri's water quality depends on whether you are on a river-sourced system, an Ozark aquifer well, or an alluvial groundwater system.
1. Check your specific location at the homepage. We show available PFAS and other contaminant data by ZIP code. 2. Residents near Whiteman AFB (Johnson County and surrounding areas) should verify whether their water system has been tested for PFAS. Private well owners within several miles of the base should pursue testing. 3. Ozark well owners – while your water is likely clean – should be aware that karst geology means contamination can appear suddenly if a source is introduced uphill or upstream from your well. Sinkhole setbacks and wellhead protection matter more in karst terrain than anywhere else. 4. Review our water filter guide for options matched to your specific situation. A detailed water report provides context for your area.
Missouri's water history reflects its position at the crossroads of the continent. The confluence of the Missouri and Mississippi rivers at St. Louis has been a center of commerce, industry, and settlement for centuries, and the water has borne the consequences.
St. Louis's industrial history is one of the most complex in the Midwest. Lead smelting (the city was the national center of lead production), chemical manufacturing, and nuclear materials processing have all left environmental legacies. The Mallinckrodt Chemical Works processed uranium for the Manhattan Project in downtown St. Louis, and waste from that operation was later dumped in north St. Louis County – the Coldwater Creek site now being remediated under Superfund authority.
Whiteman AFB, originally known as Sedalia Air Force Base, has been in operation since 1942. It became the sole operating base for the B-2 Spirit bomber in 1993. Like most military airfields, it used AFFF in firefighting training for decades. The PFAS investigation at Whiteman is part of the DoD's nationwide program and includes sampling of both on-base and off-base groundwater.
The Ozark National Scenic Riverways – including the Current and Jacks Fork rivers – represent some of the cleanest waterways in the central United States. These spring-fed rivers emerge from the deep limestone aquifer at temperatures near 58°F year-round and with remarkably consistent water quality. Protecting these springs from surface contamination in the karst landscape is an ongoing challenge as agricultural activity, residential development, and waste disposal encroach on recharge areas.
Kansas City's water system has invested in multiple treatment plant upgrades over the past decade, driven in part by increasing levels of atrazine (an agricultural herbicide) in the Missouri River during spring planting season. The city operates one of the more advanced surface water treatment trains in the region, including ozone disinfection and biological activated carbon filtration.
Missouri's rural water infrastructure, like that of many Midwestern states, includes hundreds of small systems serving communities of a few hundred to a few thousand people. Many of these systems operate on tight budgets with minimal staffing. The Missouri Rural Water Association provides technical assistance, but funding gaps persist, and emerging contaminants like PFAS represent a cost that many small systems are not equipped to bear.
Check your address to see what data is available for your part of Missouri. In a state where geology, industry, and agriculture all shape water quality, your local conditions are what matter.