Warren County water quality

Updated 2026-10-22 · Ohio · Affiliate disclosure

We read 10 results from Warren County’s 2025 water quality report. No results over a legal limit; 1 above a health goal or guideline.

Serves about 78,299 people · Water system ID OH8301512 · Read the district’s 2025 report (opens in a new tab)

Open this district in the water lookupCompare with your own test results, see the district map and get matched filters.

Results from the 2025 report

Each number is copied from the district’s report and links to the page it’s printed on. Where the report lists several plants, wells or purchased water, the highest is shown.

ContaminantResultHealth goalLegal limitWhat it means
Lead90th percentile of 65 homes tested, 0 over the action level · listed as a violation in the report · Customer taps (Jan-Jun 2025), highest of 2 sources · 2025 report, page 51.95 ppb0.2 ppb15 ppb (action level)Above the health goal9.8x the health goal
Bariumsingle sample · listed as a violation in the report · Franklin Area plant, highest of 2 sources · 2025 report, page 50.04 ppm2 ppm2 ppmBelow the health goal
Chlorineaverage · range 1.05 to 1.28 · listed as a violation in the report · Distribution system · 2025 report, page 51.16 ppmNone set4 ppmBelow the legal limit
Copper90th percentile of 64 homes tested, 0 over the action level · listed as a violation in the report · Customer taps (Jul-Dec 2025), highest of 2 sources · 2025 report, page 50.2 ppm0.3 ppm1.3 ppm (action level)Below the health goal
Disinfection byproducts (HAA5)highest running annual average · range ND to 8.1 · listed as a violation in the report · Distribution system · 2025 report, page 56.27 ppbNone set60 ppbBelow the legal limit
Disinfection byproducts (TTHM)highest running annual average · range 5.7 to 21.9 · listed as a violation in the report · Distribution system · 2025 report, page 521.9 ppbNone set80 ppbBelow the legal limit
Fluorideaverage · range 0.85 to 1.05 · listed as a violation in the report · Richard Renneker plant, highest of 2 sources · 2025 report, page 50.97 ppm1 ppm4 ppmBelow the health goal
Nitrate (as N)single sample · listed as a violation in the report · Franklin Area plant, highest of 2 sources · 2025 report, page 51.07 ppm10 ppm10 ppmBelow the health goal
Bromodichloromethaneaverage · range 1.6 to 6.2 · Distribution system · 2025 report, page 55.8 ppbNone setNoneNo health limit
Chloroformhighest measured · range 1.1 to 13 · Distribution system · 2025 report, page 513 ppbNone setNoneNo health limit

Utility results describe the whole system, measured where water enters the pipes, not your tap. Your home’s plumbing can add lead or copper.

What you can do

Nothing here is an emergency notice: if the district has a violation, it must tell customers directly. If you’d like to lower these at your tap, these are the treatments that remove them, and the catalog shows the models certified for each. Ranking is by certified removal; commissions never change the order.

Lead

Found: Lead

What removes it: Certified carbon block or RO.

See filters that remove itWhat water filter removes lead?

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