F19/100
Oak Creek Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 32,104 residents · Wisconsin
What's In Oak Creek's Tap Water?
69
Contaminants Tested
0
Exceed EPA Limits
1
Above EPA Goals
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Lead (90th percentile) | 0.002 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
2
Violations (last 5yr)
1
Unresolved
1
Health-Related
TIER 2Resolved
Treatment technique violation
When: October 17, 2024 – May 29, 2025Rule: Ground Water RuleEnforcement: Resolving — corrective action underway
TIER 3Unresolved
Disinfection byproduct treatment technique failure
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Water Utility Details
OAK CREEK WATERWORKS
Population Served
32,104
Water Source
Surface Water
System ID
WI2410172
Frequently Asked Questions About Oak Creek Water
Is Oak Creek tap water safe to drink?
Oak Creek, Wisconsin tap water receives a grade of F (19/100), which is considered failing. 0 contaminant(s) exceed EPA maximum contaminant levels and 58 violation(s) are on record. Residents should consider using an NSF-certified water filter to reduce contaminant exposure.
What contaminants are in Oak Creek's water?
Of the 69 contaminants tested in Oak Creek's water supply, the most notable include Lead (90th percentile). No contaminants exceed EPA legal limits. 1 contaminant(s) exceed EPA health goals (MCLGs), which are non-enforceable targets set at levels with no known health risk.
Does Oak Creek have any water quality violations?
Yes, Oak Creek has 58 EPA violation(s) on record, with the most recent in 2024. Violation types include TT, Other, MR. 5 of these are health-based violations, which are the most serious category.
Do I need a water filter in Oak Creek?
Oak Creek water meets EPA standards, so a filter is not strictly necessary. However, some residents prefer the added security of a water filter. EPA health goals (MCLGs) are stricter than legal limits and are set at levels with zero expected health risk. 1 contaminant(s) exceed these stricter goals.
Where does Oak Creek's tap water come from?
Oak Creek's drinking water is sourced from surface water and supplied by OAK CREEK WATERWORKS. The system serves approximately 32,104 people. Surface water sources include rivers, lakes, and reservoirs.
How often is Oak Creek's water tested?
Under the Safe Drinking Water Act (SDWA), water utilities are required to regularly test for over 90 contaminants. Testing frequency varies by contaminant — some are tested monthly, others quarterly or annually. Oak Creek's water systems must report results to the EPA and publish an annual Consumer Confidence Report (CCR). The data on this page reflects the latest available EPA testing data.
How does Oak Creek's water compare to other cities in Wisconsin?
Oak Creek's water quality score of 19/100 earns a grade of F, which is considered failing. This is a concerning score that suggests significant water quality issues. Visit our Wisconsin state page to see how all cities in the state compare.
What should I do if I'm concerned about Oak Creek's water quality?
If you have concerns about Oak Creek's tap water, consider these steps: (1) Request your utility's annual Consumer Confidence Report for detailed local data. (2) Get your water independently tested through a state-certified laboratory. (3) Consider an NSF-certified water filter rated for the contaminants found in your area. (4) Contact your water utility (OAK CREEK WATERWORKS) with specific questions. (5) Report water quality issues to your state drinking water program or the EPA Safe Drinking Water Hotline at 800-426-4791.