Indiana Water Quality Rankings 2026: Best & Worst Cities

This page ranks the 32 Indiana cities whose water systems we have matched to EPA records. Every city starts at 100 points and loses points for health-based EPA violations in the last five years (SDWIS 2026Q2), its most recent Lead and Copper Rule 90th-percentile result, PFAS detected in EPA's 2023–2026 UCMR5 monitoring, and 2012–2019 compliance samples that averaged near or above a limit. Letters follow fixed bands (A ≥90, B ≥80, C ≥70, D ≥60, F below 60). Cities run from the highest score (Greenwood) down to the lowest (Lawrence); ties are ordered by population served. See the full scoring methodology for every deduction and the data vintages. 8 further Indiana cities are listed at the bottom without a grade because we have not yet matched them to an EPA water system.

What your city's grade means

An A or B grade points to water that consistently tests within federal safety limits, while a C suggests moderate issues worth watching and a D or F flags contaminants or compliance problems serious enough to act on. These grades describe system-level water leaving the treatment plant — they can't account for your home's own plumbing, so older houses with lead service lines or fixtures can add contaminants after the water arrives. For a contaminant-by-contaminant view, see the Indiana contaminant breakdown or drill into the county-level rankings.

What Indiana residents should do

• Find your city in the ranking below and open its full report for its violation history, lead results and PFAS table.
• See how Indiana compares against the best-rated and worst-rated cities nationwide.
• Test your home's water if you have concerns — the most common issues involve lead, PFAS, and arsenic.
• Check whether your utility still has lead service lines in Indiana — EPA's inventory counts lead pipes by water system, a risk that plant-level grades cannot capture. Read the lead guide for testing and filter options.
• If treatment makes sense for your situation, compare certified water filters matched to the contaminants found in your area.

This ranking covers 40 Indiana cities. 32 of them are matched to an active EPA-registered community water system (PWSID). Those 32 systems report serving 2,918,159 people in EPA's Safe Drinking Water Information System (SDWIS).

Of 32 cities of the 40 Indiana cities we can grade from EPA records, 29 cities (91%) grade B or better, 2 sit in the C range and 1 grade D or F. The average score is 93/100. 8 cities are not graded because they have not been matched to an EPA system yet.

EPA records 9 health-based violations in the last five years across 5 cities. Monitoring and reporting violations (21 in the same window) are paperwork lapses and cost far fewer points.

32 cities have a Lead and Copper Rule 90th-percentile result from 2020 or later: 6 cities at 5 ppb or more.

EPA's UCMR5 PFAS monitoring (2023–2026) covers 32 cities: PFAS were detected in 11 cities, and PFOA or PFOS reached EPA's 4 ppt limit in 5 cities.

Evansville scores highest (100) and Lawrence lowest (59), a 41-point spread.

The clearest hard data for Indiana is EPA's service line inventory, updated 2026-08-18 (Q2 2026). 1,367 Indiana systems inventoried 2,119,585 service lines: 169,443 confirmed lead plus 21,518 galvanized lines requiring replacement, spread across 119 systems. The bigger number is 545,847 lines (26%) whose material is still unknown — more than one line in four — and EPA treats unknown lines as possible lead until a utility verifies them.

Of the 32 city-linked Indiana utilities with an inventory on file, 23 report at least one lead or galvanized-requiring-replacement line, 1 reports none but still has a quarter or more of its lines unverified, and 8 report no lead with most lines verified. The largest, CITIZENS WATER - INDIANAPOLIS (Indianapolis, 880,345 served), reports 56,766 lead lines and 195 galvanized requiring replacement.

Our Indiana water guide flags nitrates, lead, atrazine and other herbicides, and disinfection byproducts as the contaminants of regional concern. Nitrate (EPA MCL 10 mg/L (as nitrogen)) can cause methemoglobinemia ("blue baby syndrome") in infants under six months; Lead (EPA action level 0.015 mg/L (15 ppb); health goal 0) harms brain development in children and raises blood pressure and kidney risk in adults; Atrazine (EPA MCL 0.003 mg/L) is associated with cardiovascular and reproductive effects; Disinfection byproducts (regulated as TTHM (80 ppb) and HAA5 (60 ppb)) are associated with increased cancer risk over long exposure.

Source water explains a lot of the pattern in Indiana. Disinfection byproducts are a surface-water signature: chlorine reacts with organic matter in rivers and reservoirs, so byproducts tend to run higher where systems chlorinate surface water. Arsenic is naturally occurring and tends to show up in groundwater, leaching from bedrock into aquifers rather than arriving from pollution. Nitrate and atrazine follow fertilizer, manure and septic loading, so they are most often a concern for systems drawing shallow groundwater in farm regions. PFAS are tied to specific sites — industrial discharges, firefighting-foam use at airports and bases — rather than to geology, so contamination is local and can affect either source type. Lead is different again: it enters after treatment from service lines and household plumbing, which is why the inventory figures above matter more than plant-level results. The Consumer Confidence Report your Indiana utility mails each year states whether your system draws surface water or groundwater.

The best water quality in Indiana is found in Greenwood with a score of 100/100 and a grade of A. This puts Greenwood among the top-performing cities in the country for drinking water safety.

The most concerning water quality is in Lawrence scoring 59/100 with a grade of F. Residents may want to consider home water testing and filtration options.

The statewide average score is 93/100, which is 5 points above the national average of 88/100. Over half (72%) of Indiana cities score above the national average, though some areas face challenges.