Vigo County, IN Water Quality (2026): PFAS & Lead

Vigo County, Indiana: drinking water report. Vigo County in western Indiana has about 107,000 residents, with Terre Haute as the county seat.

Water Quality in Vigo County, IN

Vigo County in western Indiana has about 107,000 residents, with Terre Haute as the county seat. Indiana American Water draws from the Wabash River, treating water at a plant that has been upgraded in recent years. The Wabash River drains a massive agricultural and industrial watershed across central Indiana before reaching Terre Haute, carrying the accumulated runoff and discharges along the way.

What the Data Shows

The Wabash River at Terre Haute carries elevated nutrient levels from upstream agriculture. According to IDEM's 2024 watershed assessment, nitrate at the Terre Haute intake averaged 5.8 mg/L during spring – below the MCL but high enough to drive disinfection byproduct formation during treatment. Trihalomethanes in the distribution system have periodically approached the 80 ppb MCL during warm months.

The former Hulman Regional Airport and Terre Haute Air National Guard Base have documented AFFF use. A 2024 IDEM PFAS investigation found PFOS at 13 ppt in monitoring wells near the facility. The Mead Corporation's former paper mill in the county also contributed industrial contamination to the Wabash River floodplain.

What Residents Should Do

Terre Haute's river-sourced water is treated to meet all standards, but the high-nutrient source water means disinfection byproducts are the most relevant household concern. These byproducts form when chlorine reacts with organic matter in the water, and concentrations tend to increase in summer.

Check your water for current results. A carbon block filter is specifically effective at reducing disinfection byproducts. For PFAS, reverse osmosis adds comprehensive protection. Our water filter guide covers both approaches. Get your detailed report for seasonal patterns, and visit our Indiana page for statewide data.