WaterVerge

Is Eldorado, OH Tap Water Safe to Drink?

Graded A- — but Copper was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

539 residents served 1 water system PWSID: OH6800512
Overall Score
89.5 / 100
Violations
2 active
Last Updated
May 2026
Source
Groundwater
#40 of 511 in Ohio Top 18% nationally
Local Government
Moderate data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
A-GRADE
Water Quality Grade
89.5/100
waterverge.com
A- 89.5/100

Eldorado, OH — Water Quality Report

Eldorado's drinking water received a grade of A- (89.5 out of 100), indicating good water quality. The city's 1 water system serves approximately 539 residents using groundwater.

Lead levels were measured at 2.0 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program.

The system has 11 violations on record, including 0 health-based violations. 2 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Eldorado's water

Eldorado ranks #40 out of 511 cities in Ohio for water quality, placing it one of the best in the state.

Eldorado relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.

As a small community water system, Eldorado may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.

Quality Breakdown

Water quality score

See methodology →
89.5 out of 100 Grade A-
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
43.5/45
A
Historical violation record including health-based and monitoring violations.
Lead & Copper
16/20
B
Lead at 2.0 ppb (90th percentile).
Contaminants
17/20
B
PFAS + legacy contaminant analysis.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Eldorado, OH water safe to drink?

Use Caution

Eldorado's tap water meets most EPA standards but has areas that warrant attention. With a grade of A- (89.5/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 539 residents using groundwater (wells).

2
Active Violations
2.0 ppb
Lead (90th %ile)
2 events
Disaster History

Recent water quality updates for Eldorado

A timeline of significant water quality events, violations, and data updates.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Eldorado's water quality assessment. Grade: A- (89.5/100).

Violation
1 drinking water violation recorded

Contaminants: Consumer Confidence Rule.

Violation
1 drinking water violation recorded

Contaminants: Coliform (TCR).

Disaster
HURRICANE KATRINA EVACUATION

Federal disaster declaration (FEMA DR-3250). Hurricane event — may have impacted local water infrastructure.

Disaster
SEVERE STORMS & FLOODING

Federal disaster declaration (FEMA DR-831). Flood event — may have impacted local water infrastructure.

Violation
8 drinking water violations recorded

Contaminants: Arsenic, Cadmium, Chromium.

Key contaminant findings

Based on the most recent EPA sampling data for Eldorado's water supply.

Lead Within Limits
Detected: 2.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Copper Exceeds Limit
Detected: 217.00 mg/L Limit: 1.3 mg/L (EPA Action Level)

Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.

Violation history

Eldorado's water system has 11 total violations on record, including 0 health-based violations. 2 remain unresolved. 1 violation was issued in the last 5 years.

OtherMR
Most recent violations:
Nov 2021 Consumer Confidence Rule Open
Apr 2010 Coliform (TCR) Resolved
Oct 1984 Arsenic Resolved
Oct 1984 Cadmium Resolved
Oct 1984 Chromium Resolved

Flood & environmental risk

Preble County has experienced 2 federally declared disasters since 1989. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies.

HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3250
SEVERE STORMS & FLOODING
Flood FEMA DR-831

Where does Eldorado's water come from?

Eldorado's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 539 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.

What Eldorado residents can do

Request your utility's CCR

Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
2.0 ppb
EPA Action Level: 15 ppb · 13% of limit
Safe Level
Copper (90th percentile)
Inorganic
Over Limit
217.00 mg/L
EPA Action Level: 1.3 mg/L · +20% over limit
Exceeds Limit
Compliance Record

Violation summary

11
Total violations
0
Health-based
2
Active / unresolved
Nov 2021
Most recent violation
Compliance Record

Violations & advisories

11 Total
2 Active
0 Health-based
9 Resolved
Violations by category
Inorganic Chemicals
6
Consumer Confidence Rule
1
Total Coliform Rule
1
Arsenic Rule
1
Nitrate Rule
1
Nov 2021 Active
Consumer Confidence Rule
Other Violation 0
Active
Compliance Violation
Monitoring 0
Apr 2010 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Apr 2010
Oct 1984 Resolved
Arsenic
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 1987
Oct 1984 Resolved
Cadmium
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 1987
Oct 1984 Resolved
Chromium
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 1987
Oct 1984 Resolved
Fluoride
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 1987
Oct 1984 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 1987
Oct 1984 Resolved
Barium
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 1987
Oct 1984 Resolved
Mercury
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 1987
Oct 1984 Resolved
Selenium
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 1987
Industrial pollution

Top industrial polluters within 10 miles of Eldorado

Industrial polluters nearby

Reported releases to surface water by facilities near Eldorado, ranked by pounds discharged annually.

Total reported releases to surface water: 1,500 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
PROVIMI NA INC
Food · CARGILL INC
LEWISBURG, OH45338
Manganese compounds7509.5 mi
PROVIMI N.A. INC.
Food · CARGILL INC
LEWISBURG, OH45338
Copper compounds7509.5 mi
PARKER HANNIFIN LEWISBURG PLANT
Fabricated Metals · PARKER HANNIFIN CORP
LEWISBURG, OH45338
7.7 mi
CHAMPION TARGET
Miscellaneous Manufacturing · VISTA OUTDOOR INC
RICHMOND, IN47374
9.5 mi
ENVIROTECH EXTRUSION
Plastics and Rubber · NA
RICHMOND, IN47374
9.7 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Environmental Risk

Flood & disaster history

2
Declared disasters
Sep 2005
Most recent
Hurricane
Most common type

Preble County has experienced 2 federally declared disasters since 1989. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3250
Jun 1989
SEVERE STORMS & FLOODING
Flood FEMA #831

Recommended water filters

Based on contaminants detected in Eldorado's water supply, we recommend the following filter types.

🔧
For Copper
Reverse Osmosis or KDF Filter
Copper exceeds the EPA action level of 1.3 mg/L

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 2.0 15 ppb Inorganic Safe
Copper (90th percentile) 217.00 1.3 mg/L Inorganic Over Limit
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has increased by 2.0 ppb from 1993 (0.0 ppb) to 2025 (2.0 ppb).

Copper level (90th percentile)

Latest reading: 217.000 mg/L (2005)

EPA action level: 1.3 mg/L

Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
539
Water Systems
1
Water Source

Where Eldorado's water comes from

Groundwater

Eldorado's drinking water is drawn from underground aquifers through wells.

Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.

Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.

The system is operated by local government ownership and serves approximately 539 people through 1 water system.

Infrastructure

Water systems serving Eldorado

System Name PWSID Population Source
ELDORADO, VILLAGE OF OH6800512 539 GW
Regional Comparison

How Eldorado compares

Full Ohio rankings →

Eldorado's score of 89.5/100 is above the average of 58/100 among major Ohio cities. It outscores 10 of 10 nearby cities.

Eldorado (this city)
89.5
Columbus
35.5
Cleveland
85.5
Cincinnati
36.8
Toledo
78
Kent
38.2
Ohio avg
58
City Profile

About Eldorado, OH

Wikipedia →

Eldorado is a village in Preble County, Ohio, United States. The population was 458 at the 2020 census. It is part of the Dayton Metropolitan Statistical Area.

Economic Profile
$66,750
Median Income
$113,123
Median Home Value
$1,053/mo
Median Rent
5%
Unemployment
Community
29.9
Median Age
353
People / sq mi
17.4%
College Educated
79.9%
Homeownership
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Frequently asked questions

Is Eldorado, OH tap water safe to drink?

Eldorado's water quality earned a grade of A- (89.5/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #40 out of 511 cities tested in Ohio.

What contaminants are in Eldorado's water?

Lead was measured at 2.0 ppb (90th percentile). 11 violations are on record.

How is Eldorado's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in Eldorado?

Based on current data, basic filtration should suffice for additional peace of mind.

Where does Eldorado's water come from?

Eldorado's water is sourced from Groundwater. The city has 1 water system serving approximately 539 residents.

Is Eldorado's groundwater at risk of contamination?

Eldorado uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 11 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.

How does Eldorado's water compare to other cities?

Eldorado ranks #40 out of 511 cities in Ohio (better than 92% of state cities) and #2818 out of 15744 cities nationally (82th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

Does Eldorado's small water system affect quality?

Eldorado's system serves approximately 539 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 11 violations on record.