Free Indiana water report: PFAS & lead levels for every water system, worst-affected cities, and EPA violations. Check your ZIP.
Indiana's drinking water serves approximately 6.8 million residents through a mix of surface water and groundwater systems. The state's water infrastructure reflects its geography: northern Indiana draws heavily from Lake Michigan and glacial aquifers, while central and southern regions depend on rivers, reservoirs, and deeper groundwater formations. Indianapolis, the largest city, pulls from three reservoirs – Eagle Creek, Morse, and Geist – supplemented by the White River. Rural communities across the state rely overwhelmingly on private wells and small public systems tapping local aquifers. The Indiana Department of Environmental Management (IDEM) oversees roughly 4,400 public water systems, but the patchwork of small systems means monitoring coverage and treatment capacity vary dramatically from county to county.
Manufacturing has shaped Indiana's water profile more than almost any other factor. The state's industrial corridor – running from Gary and Hammond in the northwest through Indianapolis and down to Evansville – includes steel production, automotive manufacturing, chemical processing, and electronics fabrication. Each of these industries has historically used PFAS-containing compounds in processes ranging from chrome plating to fire suppression.
The EPA's UCMR5 monitoring program has expanded PFAS testing to water systems across Indiana, and results confirm what the state's industrial history would suggest: detections are widespread, though concentrations vary significantly by location. Northwestern Indiana, near the Lake Michigan industrial corridor, has shown some of the highest readings. Communities near military installations – including Grissom Air Reserve Base in Miami County – have documented PFAS contamination in surrounding groundwater.
Indiana has not yet adopted state-specific PFAS maximum contaminant levels, relying on federal EPA standards. IDEM has conducted supplemental sampling in areas identified as high risk, particularly near known AFFF (aqueous film-forming foam) usage sites and industrial facilities with PFAS in their discharge permits. The Indiana Finance Authority, which manages the state's drinking water revolving fund, has begun directing resources toward PFAS treatment infrastructure for affected communities.
Rural well users face a particular gap: UCMR5 only covers public water systems, leaving the estimated 600,000 Indiana residents on private wells without systematic PFAS monitoring. Voluntary testing programs exist but participation remains low.
Among Midwestern states, Indiana occupies a middle position on PFAS contamination. Michigan and Minnesota – with major 3M and military contamination sites – have more severe hotspots and stricter state regulations. Ohio and Illinois have similarly industrial profiles but have moved faster on state-level PFAS standards. Indiana's reliance on federal standards means utilities face less regulatory pressure to test and treat than their counterparts across the border in Michigan, where state MCLs for several PFAS compounds are among the strictest in the country.
The state's groundwater dependence is a double-edged factor. Groundwater is naturally filtered through soil and rock, which removes many surface contaminants. But once PFAS reaches an aquifer, it persists for decades – these compounds do not break down under normal environmental conditions. Indiana's glacial aquifers in the north are particularly vulnerable because the sandy, permeable soils that make them productive also allow surface contaminants to reach the water table relatively quickly.
According to IDEM's 2024 water quality assessment, approximately 30% of assessed stream miles in Indiana are impaired for one or more designated uses, with agricultural runoff and legacy industrial discharge as leading causes.
Water quality in Indiana depends heavily on where you live and whether you are on a public system or a private well.
1. Check your specific location using our free tool at the homepage. Municipal water data is available by ZIP code, and we show which contaminants have been detected in your service area. 2. Private well owners should consider independent PFAS testing, especially if your property is within 5 miles of a military base, airport, industrial facility, or farm that received biosolids. Testing kits certified for EPA Method 533 are available through several national labs. 3. Review filtration options if your data shows PFAS detections. Activated carbon filters handle shorter-chain PFAS, while reverse osmosis systems are more effective across the full range of compounds. Our water filter guide breaks down which technologies actually work. 4. For a complete picture of your local water, request a detailed water report that compiles federal, state, and utility-level monitoring data for your address.
Indiana's water quality story is inseparable from its manufacturing legacy. The Calumet region in northwest Indiana – encompassing Gary, East Chicago, and Hammond – was the backbone of American steel production for a century. US Steel, Inland Steel, and dozens of supporting operations discharged waste into the Grand Calumet River and directly into Lake Michigan for decades before the Clean Water Act began to change practices in the 1970s.
The Grand Calumet River remains one of the most contaminated waterways in the Great Lakes basin. EPA Superfund sites in the region include the USS Lead facility in East Chicago, where lead and arsenic contamination prompted the relocation of an entire public housing complex. While these legacy contaminants are distinct from PFAS, they illustrate the depth of industrial contamination in the region.
Grissom Air Reserve Base in north-central Indiana is the state's most prominent military PFAS site. AFFF used in firefighting training exercises contaminated groundwater that feeds private wells and small community systems in Miami and Cass counties. The Department of Defense has provided bottled water and connected some affected residents to clean municipal supplies, but long-term remediation is ongoing.
Agricultural contamination adds another layer. Indiana ranks among the top 10 states for corn and soybean production, and the associated fertilizer and pesticide applications have driven nitrate contamination in shallow aquifers across the central and southern portions of the state. While nitrate is a separate issue from PFAS, the combination of agricultural chemicals, industrial legacy compounds, and emerging contaminants like PFAS creates a complex picture for the state's drinking water.
Indianapolis has invested significantly in its water infrastructure over the past decade. Citizens Water, the city's utility, completed a $500 million upgrade to its treatment systems and has been expanding monitoring for emerging contaminants. But outside the major metros, small systems serving rural communities often lack the funding and technical capacity to address new threats like PFAS.
Check your specific address to see the latest data for your area. In a state where water sources and treatment capacity vary widely, your location determines your exposure.