Water system
Ada Village
EPA ID OH3300012 · Hardin County · 5,334 people served · owned by a local government
Ada Village treats its own water from Groundwater wells (3 wells).
The system's record
- Active wells
- 3
- Serves
- 5,334 people · Hardin County
- EPA ID
- OH3300012
About this area's water
Did you know
- Ada's sewage plant flow drops by more than 40% when Ohio Northern University lets out for the summer — roughly 1.0 million gallons a day with students in session against 0.59 million without — so the plant was designed…
- Probably more than a hundred abandoned wells puncture the confining layer above Ada's aquifer, each one a direct pathway from the ground surface down to the village's drinking water.
- Among the 33 potential contaminant sources Ada has mapped inside its wellhead protection area is a football factory: Ada is home to the only plant in the United States that makes leather footballs.
- Meter-pit inspections and excavations confirmed Ada's distribution system has no lead, no galvanized pipe requiring replacement, and no unknown-material service lines at all.
- Ada was platted as 'Johnstown' in 1853 and took its present name from its post office, which was named after the postmaster's daughter.
History6
- 1853Village platted as 'Johnstown' by S. M. Johnson.
- 1850sA post office was established as the Ada Post Office, named after the postmaster's daughter Ada, and the village took that name. (The exact year could not be pinned down in the sources checked.)
- 1871Ohio Normal School, now Ohio Northern University, founded by Henry Solomon Lehr — eighteen years after Ada was first settled — driving the village's growth.
- 1910President William Howard Taft delivered Ohio Northern's fall commencement address in Ada; he remains the only sitting U.S. president to visit the village.
- 1955Ada's first activated-sludge wastewater treatment plant built, designed for an annual average flow of 860,000 gallons per day.
- 1996Village adopted its 'Wellhead Protection Education and Management Plan,' prepared in April by S.A. Smith Consulting Services and endorsed by Ohio EPA that year.
Treatment & pressure
How it is treated
Three wells at the water treatment plant draw from the carbonate aquifer beneath Ada; water in that aquifer generally stands 20 to 40 feet below the ground surface. The well water is aerated, softened, stabilized, filtered, chlorinated and fluoridated before being pumped into the distribution…
Source: adaoh.gov
Water pressure
Not published — no psi figures, pressure zones, storage volumes, or main mileage appear in the 2025 CCR or anywhere on the village website.
What it costs
Ada publishes no water or sewer rate schedule. The village's ordinance and resolution indices covering 2020 through 2026 contain no water or sewer rate ordinance — the only…
Water quality & impurities10
| Contaminant | Level | Limit | Year |
|---|---|---|---|
| Total Chlorine Range 2.0-2.2 ppm; disinfectant residual. | 2.1 ppm | 4 (MRDL) | 2025 |
| Total Trihalomethanes (TTHM) Range 30.1-47.0 ppb — the closest any Ada result comes to its limit, at about 59% of the MCL. | 47 ppb | 80 | 2025 |
| Haloacetic Acids (HAA5) Range 4.7-5.6 ppb; disinfection byproduct. | 5.6 ppb | 60 | 2025 |
| Fluoride Range 0.9-1.1 ppm; naturally occurring plus water additive. | 0.99 ppm | 4 | 2025 |
| Nitrate About 3% of the limit — very low for an agricultural county. | 0.297 ppm | 10 | 2025 |
| Barium Monitored less than annually because levels change slowly; well below the limit. | 0.0089 ppm | 2 | 2021 |
| Cyanide Discharge from plastic, fertilizer and steel/metal factories; 0.5% of the limit. | 1 ppb | 200 | 2024 |
| Lead Zero individual results over the action level; 0 of 20 samples exceeded it. The village reports no lead… | 0.2 (90th… ppb | 15 (Action… | 2025 |
| Copper Zero individual results over the action level; 0 of 20 samples exceeded it. | 0.006 (90th… ppm | 1.3 (Action… | 2025 |
| Lithium Range 45.7-45.8 ppb; detected under EPA's unregulated contaminant monitoring, which exists to help decide whether… | 45.8 ppb | unregulated (no… | 2023 |
Source: adaoh.gov
EPA compliance record
Lead at the tap: 90th-percentile result 0 ppb in 2025 (action level 15 ppb).
EPA record: no health-based violations since 2015.
2 violations of any kind logged since 2020, 2 of them paperwork (monitoring, reporting, public notice or consumer report).
Projects & plans3
Recent and current work
- Wastewater treatment plant liquid-stream replacement · $14 million · 2015 · completed
Funded by a 20-year Water Pollution Control Loan Fund loan of $14,200,000, with design fees on a separate loan. Jones & Henry Engineers replaced the 1955… - Service line material verification · 2025 · completed
Village staff used historical records and water line installation dates to narrow the undocumented service lines, then field-verified the remainder through… - Drinking Water Source Protection Plan revision · 2024 · completed
The April 1996 'Wellhead Protection Education and Management Plan' by S.A. Smith Consulting Services, endorsed by Ohio EPA in 1996, was revised into a Drinking…
Supply stress
Ada's wellfield draws from a carbonate aquifer that Ohio EPA and the village's own assessment rate as highly susceptible to contamination, for three stated reasons: water in the aquifer stands only 20 to 40 feet below the ground surface; probably more than 100 unused wells within the protection area breach the confining layer and provide…
Source: adaoh.gov
Sewers
Sanitary
The Ada WWTP (Ohio NPDES permit 2PB00050*ND) sits on about five acres bordered by a railroad, Grass Run Creek and County Road 44, and discharges to Grass Run Creek. A 1955 activated-sludge plant designed for 860,000 gpd was replaced under a $14.2 million WPCLF-funded project; the new liquid stream — designed for 2.0 mgd average flow, 6.0…
Storm
Not documented — the village publishes no stormwater utility, fee, or drainage plan. Its Ohio EPA reporting is for sanitary sewer overflows rather than combined sewer overflows, which indicates a separate sanitary system.
Main supplier in 1 ZIP code
Serves
Main water supplier in 1 ZIP code
- 45810 · Ada66% of residents
Population-weighted resident shares; a ZIP code can have more than one system on record. Recomputed from each ZIP's own system list, not from the map's cached footprint.
Buys from · Sells to
Ada Village does not buy water from another system on record; it treats its own source water.
No other system is on record buying water from Ada Village.
Photograph
On the map
Show this system's territory on the map — 1 ZIP code in all.
Sources
U.S. EPA SDWIS and Community Water System Service Area Boundaries (v3, 2026), Ohio EPA primacy data, 2020 census blocks: the system serving most residents, traced through purchases to the treating utility; Ohio EPA 2023 Sewer and Water Rate Survey (Ohio State, May 2025) for household bills; Ohio EPA DEFA loan awards since 2016 for the loans paragraph · EPA SDWIS · EPA service area boundaries · Ohio EPA drinking water · Ohio EPA rate survey
Notable facts: adaoh.gov, adaoh.gov, en.wikipedia.org
History: en.wikipedia.org, adaoh.gov, adaoh.gov
Water quality: adaoh.gov
Water pressure: adaoh.gov, adaoh.gov
Capital projects: adaoh.gov, adaoh.gov, adaoh.gov
Sewers: adaoh.gov, adaoh.gov, adaoh.gov
Treatment: adaoh.gov
Supply stress: adaoh.gov