WaterQ

Indiana Tap Water Quality Rankings 2026: 19th in Nation | WaterQ

Alex Carter
By Alex Carter
Water Quality Researcher ยท Published 2026-06-23

Indiana ranks 19th out of 50 states in drinking water quality, earning an average score of 85 and a letter grade of B. This grade reflects the performance of the state's 431 public water systems, which serve a population of 5,165,562. However, a total of 15,712 violations highlights the need for ongoing vigilance and infrastructure improvements across the state.

Key Findings for Indiana

Reviewing EPA SDWIS data for 2026, here's what defines Indiana's water quality landscape:

  • As part of the agricultural Midwest, some regions may experience elevated levels of nitrates in source waters due to runoff from farmland.
  • In industrialized Rust Belt areas, older municipal piping and industrial history increase the risk of lead service lines and chemical contaminants.
  • With 431 water systems serving more than 5.1 million residents, maintaining compliance across diverse rural and urban systems remains a complex challenge.

Most Common Contaminants in Indiana

Here's what Indiana residents should know about the contaminants most relevant to their water:

Nitrate

Frequently found in agricultural areas, nitrate levels can rise in source water due to fertilizer runoff and agricultural activity.

Lead

Older housing infrastructure and industrial history in the Rust Belt region can lead to elevated lead levels if older service lines or fixtures corrode.

Disinfection Byproducts

Formed when chemical disinfectants react with organic matter in source waters, these byproducts are a common compliance challenge for municipal systems.

Indiana's Best and Worst Cities for Water Quality

Water quality can vary significantly between individual municipalities and water systems across Indiana. We recommend checking our detailed city-by-city database to view specific testing results and violation histories for your local utility. Explore the full breakdown on our Indiana water systems page.

What Indiana Residents Should Do

Given Indiana's 19th place ranking, here's what matters most for residents:

  1. Search for your local water system on the EPA database or your utility's website to review their annual Consumer Confidence Report.
  2. If you rely on a private well, schedule regular testing for common contaminants like nitrates and coliform bacteria, which are not monitored by public systems.
  3. Consider installing a certified water filter appropriate for the specific contaminants identified in your local area's testing results.
  4. Review your utility's compliance and violation history to understand any past issues with disinfection byproducts or water quality standard exceedances.

Frequently Asked Questions

How does Indiana water quality compare to other states?

Indiana ranks 19th out of 50 states, placing it in the top half of the country for drinking water quality. It receives an overall grade of B with an average score of 85, indicating generally good water quality with some room for infrastructure improvements.

What are the most common contaminants in Indiana tap water?

Common contaminants in Indiana can include nitrate from agricultural runoff and lead from older corroding pipes in Rust Belt industrial areas. Disinfection byproducts may also form during the municipal treatment process when disinfectants react with organic materials.

Is it safe to drink tap water in Indiana?

With a grade of B and an average score of 85, Indiana's tap water is generally safe and compliant for the majority of the population of 5,165,562. However, because there are 15,712 recorded violations across the state's 431 systems, residents should check their specific local system's reports to confirm safety.

Source: EPA SDWIS 2026 Compliance Data and WaterQ National Database. For more information on our ranking process, visit our state rankings page.