A88/100
Combined Locks Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 3,609 residents · Wisconsin
What's In Combined Locks's Tap Water?
31
Contaminants Tested
0
Exceed EPA Limits
0
Above EPA Goals
EPA Violation History
5
Violations (last 5yr)
1
Unresolved
1
Health-Related
TIER 2Resolved
Treatment technique violation
When: October 17, 2024 – December 13, 2024Rule: Ground Water RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved
Disinfection byproduct treatment technique failure
When: October 17, 2024 – June 25, 2025Rule: Ground Water RuleEnforcement: Resolving — corrective action underway
TIER 3Unresolved
Violation related to Turbidity
TIER 3Resolved
Failed Level 2 Assessment under Revised Total Coliform Rule
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: January 1, 2024 – December 31, 2024Rule: Stage 2 DBPREnforcement: Resolving — corrective action underway
TIER 3Resolved
Failed Level 2 Assessment under Revised Total Coliform Rule
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: January 1, 2024 – December 31, 2024Rule: Stage 2 DBPREnforcement: Resolving — corrective action underway
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
COMBINED LOCKS WATERWORKS
Population Served
3,609
Water Source
Purchased Groundwater
System ID
WI4450409
Frequently Asked Questions About Combined Locks Water
Is Combined Locks tap water safe to drink?
Combined Locks, Wisconsin tap water receives a grade of A (88/100), which is considered excellent. Out of 31 contaminants tested, none exceed EPA maximum contaminant levels (MCLs). While the water meets federal standards, some residents may still choose to use a filter for additional peace of mind.
What contaminants are in Combined Locks's water?
31 contaminants were tested in Combined Locks's water supply. No contaminants exceed EPA legal limits (MCLs) or health goals (MCLGs), which is a positive indicator of water quality.
Does Combined Locks have any water quality violations?
Yes, Combined Locks has 8 EPA violation(s) on record, with the most recent in 2024. Violation types include TT, Other, MR. 1 of these are health-based violations, which are the most serious category.
Do I need a water filter in Combined Locks?
Combined Locks 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. All contaminants are within health goals.
Where does Combined Locks's tap water come from?
Combined Locks's drinking water is sourced from purchased groundwater and supplied by COMBINED LOCKS WATERWORKS. The system serves approximately 3,609 people. Groundwater is pumped from underground aquifers, which often provides natural filtration.
How often is Combined Locks'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. Combined Locks'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 Combined Locks's water compare to other cities in Wisconsin?
Combined Locks's water quality score of 88/100 earns a grade of A, which is considered excellent. This places Combined Locks among the better-performing water systems in Wisconsin. Visit our Wisconsin state page to see how all cities in the state compare.
What should I do if I'm concerned about Combined Locks's water quality?
If you have concerns about Combined Locks'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 (COMBINED LOCKS 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.