Water Quality in Delavan, WI: 3 Violations — Grade D
Grade D · Score 52/100 · 5 water systems · Updated 2026-05-03
Delavan's water has significant violations. Water testing and filtration are recommended.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
Compliance records maintained by the EPA for Delavan, WI log 3 violations — accumulated reportable events drawn from every local utility in the SDWIS national tracking system.
Water Quality by ZIP Code in Delavan
Water quality varies across Delavan's 1 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 53115 | D | 52 | 3 | 0 | View report → |
Water Quality Overview
Delavan, Wisconsin receives a water quality grade of D with an overall score of 52 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
The 5 water systems serving Delavan have accumulated 3 EPA violations (all monitoring/reporting type). These violations are tracked across 1 ZIP codes serving approximately 9,636 people.
What Grade D Means
A grade of D indicates significant compliance issues. Delavan's water systems have accumulated violations that suggest ongoing water quality challenges. Residents should check their specific ZIP code report and consider water testing or filtration.
Lead Levels
The average 90th percentile lead level across Delavan water systems is 0.0100 mg/L — within EPA limits. No ZIP codes exceed the EPA lead action level.
With 63% of homes built before 1986, Delavan 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
Delavan 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 Delavan
Delavan is served by 5 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 9,636 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
How to Check Your Water in Delavan
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 Delavan Water Systems
The following contaminants have been detected or caused violations across Delavan's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Gross Alpha | Radionuclides | 15 pCi/L | 1 | 1 | No |
| PFOA | PFAS | 0.000004 mg/L | 1 | 1 | No |
MCL = Maximum Contaminant Level (EPA enforceable standard). Health-based violations indicate levels that may pose direct health risks.
Delavan vs. Nearby Wisconsin Cities
How Delavan's water quality compares to similar cities in Wisconsin:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Delavan | D | 3 | 5 | 9,636 |
| Mc Farland | B | 0 | 1 | 9,676 |
| Sturgeon Bay | C | 3 | 2 | 9,760 |
| Hartland | D | 1 | 5 | 9,462 |
Common Questions About Delavan Water
These are the most common questions residents search for about water quality in Delavan, Wisconsin:
Is Delavan water hard or soft? Water hardness varies by source. Delavan's 5 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Delavan tap water? Delavan's water receives a grade of D (52/100). No health-based violations have been recorded, but home testing is always recommended.
What is the best water filter for Delavan? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Delavan vs. Wisconsin Average
Understanding how Delavan 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 Delavan.
ZIP Codes in Delavan
Delavan spans 1 ZIP code. The ZIP with the lowest water quality score is 53115. 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.