Water Quality in Mount Sterling, WI: 10 Violations — Grade F
Grade F · Score 28/100 · 1 water system · Updated 2026-05-03
Mount Sterling's water has serious compliance issues. Independent testing and filtration are strongly recommended.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
Compliance records maintained by the EPA for Mount Sterling, WI log 10 violations — accumulated reportable events drawn from every local utility in the SDWIS national tracking system.
Water Quality by ZIP Code in Mount Sterling
Water quality varies across Mount Sterling's 1 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 54645 | F | 28 | 10 | 4 | View report → |
Violation Trend
EPA violations recorded for water systems serving Mount Sterling.
Water Quality Overview
Mount Sterling, Wisconsin receives a water quality grade of F with an overall score of 28 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
The 1 water system serving Mount Sterling have accumulated 10 EPA violations, including 4 health-based violations. These violations are tracked across 1 ZIP codes serving approximately 206 people.
What Grade F Means
A grade of F indicates serious compliance issues. Mount Sterling's water systems have substantial violations. Residents should strongly consider independent water testing and appropriate filtration.
Lead Levels
The average 90th percentile lead level across Mount Sterling water systems is 0.0280 mg/L — this exceeds the EPA action level of 0.015 mg/L. 1 ZIP code exceed the EPA lead action level.
With 89% of homes built before 1986, Mount Sterling has a higher-than-average risk of lead from older plumbing. Lead solder was banned in 1986, and homes built before this date may have lead in pipes, solder joints, or fixtures.
Radon Risk
Mount Sterling is in EPA Radon Zone 1 (High risk). The EPA recommends all homes in Zone 1 areas be tested for radon. Radon is the second leading cause of lung cancer after smoking.
Water Systems Serving Mount Sterling
Mount Sterling is served by 1 community water system regulated under the Safe Drinking Water Act. These systems collectively serve approximately 206 people across 1 ZIP codes.
Each water system is identified by a Public Water System ID (PWSID) and is required to:
- Test for over 90 regulated contaminants on a regular schedule
- Report results to the EPA and state regulators
- Issue an annual Consumer Confidence Report (CCR) to all customers
- Take corrective action when violations occur
The EPA has taken 10 enforcement actions against water systems serving Mount Sterling. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Mount Sterling
Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels, violation history, and safety scores
Request your CCR — your water utility must provide an annual Consumer Confidence Report with detailed test results for all monitored contaminants
Get a home test — certified kits cost $20–$50 and test for lead, bacteria, and common contaminants. Professional lab tests ($150–$400) cover a broader panel
Consider filtration — NSF-certified filters can remove specific contaminants. Reverse osmosis removes the broadest range; activated carbon is effective for chlorine and many organics
Check for advisories — monitor your local utility website and local news for boil water advisories or system alerts
Contaminants Detected in Mount Sterling Water Systems
The following contaminants have been detected or caused violations across Mount Sterling's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Stage 1 DBP Rule | Treatment Technique | N/A | 4 | 1 | Yes |
| Stage 2 DBP Rule | Treatment Technique | N/A | 2 | 1 | Yes |
| Chlorine residual | Disinfectant | 4 mg/L | 1 | 1 | Yes |
| Lead and Copper Rule | Treatment Technique | N/A | 1 | 1 | No |
MCL = Maximum Contaminant Level (EPA enforceable standard). Health-based violations indicate levels that may pose direct health risks.
Violation Trend Over Time
Year-by-year EPA violations recorded for water systems serving Mount Sterling:
| Year | Total Violations | Health-Based |
|---|---|---|
| 2023 | 1 | 1 |
| 2024 | 3 | 3 |
Violations have increased from 1 in 2023 to 3 in 2024. This trend warrants monitoring.
EPA Enforcement History
The EPA and state regulators have taken 10 enforcement actions against water systems serving Mount Sterling. Recent actions:
| Date | Action Type |
|---|---|
| 2025-07-03 | State Order Extension |
| 2025-06-25 | State Order Extension |
| 2025-02-14 | State Informal Action |
| 2025-01-27 | State Informal Enforcement |
| 2025-01-27 | State Informal Action |
| 2024-08-28 | State Informal Action |
| 2024-08-27 | State Informal Action |
| 2024-08-27 | State Informal Enforcement |
| 2024-08-26 | State Order Extension |
| 2024-06-24 | State Informal Action |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2025-07-03.
Mount Sterling vs. Nearby Wisconsin Cities
How Mount Sterling's water quality compares to similar cities in Wisconsin:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Mount Sterling | F | 10 | 1 | 206 |
| Ferryville | D | 0 | 1 | 206 |
| Iron Belt | B | 1 | 1 | 211 |
| Saxon | D | 0 | 1 | 211 |
Common Questions About Mount Sterling Water
These are the most common questions residents search for about water quality in Mount Sterling, Wisconsin:
Is Mount Sterling water hard or soft? Water hardness varies by source. Mount Sterling's 1 water system uses a single source. Check your ZIP code report for specific hardness data.
Can I drink Mount Sterling tap water? Mount Sterling's water receives a grade of F (28/100). There are 4 health-based violations — consider filtration.
What is the best water filter for Mount Sterling? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Mount Sterling vs. Wisconsin Average
Understanding how Mount Sterling compares to the broader Wisconsin average helps contextualize your local water quality. Factors like water source, treatment methods, and infrastructure age all contribute to differences between cities in the same state.
To see how individual neighborhoods compare, check the ZIP code reports below — water quality can vary significantly even within Mount Sterling.
ZIP Codes in Mount Sterling
Mount Sterling spans 1 ZIP code. The ZIP with the lowest water quality score is 54645. Each ZIP code has its own water quality profile based on the specific water system serving that area. Check each ZIP code for detailed contaminant data, violation history, and system information.
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
- Enforcement: EPA ECHO database
- Filter recommendations: NSF/ANSI certified products
Updated daily.