Is Combined Locks, WI Tap Water Safe to Drink?
Graded B, with 5 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
77.7/100
waterverge.com Combined Locks, WI — Water Quality Report
Combined Locks's drinking water received a grade of B (77.7 out of 100), indicating good water quality. The city's 1 water system serves approximately 3,609 residents using purchased ground water.
Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 1 PFAS compound in the water supply.
The system has 8 violations on record, including 1 health-based violation. 5 remain unresolved.
What to know about Combined Locks's water
Combined Locks ranks #292 out of 446 cities in Wisconsin for water quality, placing it below average in the state.
Combined Locks purchases its water from a regional wholesaler, meaning quality depends on both the supplier's treatment and the local distribution system's condition.
PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter.
Water quality score
See methodology →Is Combined Locks, WI water safe to drink?
Combined Locks's drinking water has significant quality concerns based on EPA testing data. With a grade of B (77.7/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 3,609 residents using groundwater (wells).
Recent water quality updates for Combined Locks
A timeline of significant water quality events, violations, and data updates.
Detected at levels within current EPA limits. PFAS persist indefinitely in the environment.
Latest EPA compliance and testing data incorporated into Combined Locks's water quality assessment. Grade: B (77.7/100).
1 health-based. Contaminants: LEAD AND COPPER RULE REVISIONS, Public Notice.
Contaminants: TTHM, Total Haloacetic Acids (HAA5).
Federal disaster declaration (FEMA DR-4459). Flood event — may have impacted local water infrastructure.
Contaminants: Consumer Confidence Rule.
Key contaminant findings
Based on the most recent EPA sampling data for Combined Locks's water supply.
Well within EPA limits.
Detected but within current EPA limits. PFAS do not break down in the environment and can accumulate in the body over time. An activated carbon filter can reduce exposure.
Violation history
Combined Locks's water system has 8 total violations on record, including 1 health-based violation. 5 remain unresolved. 5 violations were issued in the last 5 years.
Flood & environmental risk
Outagamie County has experienced 4 federally declared disasters since 1973. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Fox River, Fox R.
Where does Combined Locks's water come from?
Combined Locks's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 3,609 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Fox River (river), Fox R (river).
What Combined Locks residents can do
Recommended: Activated carbon or reverse osmosis filter. This addresses the specific contaminants found in Combined Locks's water.
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.
Combined Locks's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.
Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.
Top contaminants to know
View all ↓Forever chemicals overview
National PFAS report →Violation summary
Violations & advisories
Top industrial polluters within 10 miles of Combined Locks
Industrial polluters nearby
Reported releases to surface water by facilities near Combined Locks, ranked by pounds discharged annually.
Total reported releases to surface water: 53,628 lbs
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
AHLSTROM NA SPECIALTY SOLUTIONS LLC KAUKAUNA, WI54130 | Manganese And Manganese Compounds | 24,220 | 2.6 mi |
BELGIOIOSO CHEESE - FREEDOM PLANT APPLETON, WI54913 | Nitrate compounds (water dissociable; reportable only when in aqueous solution) | 19,961 | 8.3 mi |
MCKINLEY PAPER & PACKAGING CO COMBINED LOCKS, WI54113 | Ammonia | 8,391 | 0.7 mi |
BELGIOIOSO SHERWOOD MENASHA, WI54952 | Nitrate compounds (water dissociable; reportable only when in aqueous solution) | 750 | 4.5 mi |
ESSITY PROFESSIONAL HYGIENE N.A. LLC MENASHA, WI54952 | Ammonia | 306 | 8.1 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Superfund sites within 10 miles of Combined Locks
Superfund sites nearby
Federally tracked hazardous-waste sites on the EPA National Priorities List. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.
- SCHMALZ DUMP5.6 mi
- N W MAUTHE CO INC6.0 mi
Source: EPA Superfund National Priorities List
Flood & disaster history
Outagamie County has experienced 4 federally declared disasters since 1973. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Recommended water filters
Based on contaminants detected in Combined Locks's water supply, we recommend the following filter types.
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 0.0 | 15 | ppb | Inorganic | Safe |
| 11Cl-PF3OUdS | ND | HI | µg/L | PFAS | Not Detected |
| 4:2 FTS | ND | HI | µg/L | PFAS | Not Detected |
| 6:2 FTS 6:2 FTSPFAS A fluorotelomer sulfonate commonly found at sites contaminated with aqueous film-forming foam (AFFF) used in firefighting. Health EffectsPotential liver toxicity and endocrine disruption. Less studied but identified as a contaminant of concern. EPA LimitNo individual MCL (not yet regulated) Common SourcesFirefighting foam (AFFF), airports, military bases, and industrial facilities. | ND | HI | µg/L | PFAS | Not Detected |
| 8:2 FTS | ND | HI | µg/L | PFAS | Not Detected |
| 9Cl-PF3ONS | ND | HI | µg/L | PFAS | Not Detected |
| ADONA | ND | HI | µg/L | PFAS | Not Detected |
| HFPO-DA HFPO-DA (GenX)PFAS A replacement for PFOA in manufacturing, marketed as safer but still a persistent "forever chemical." Also known as GenX. Health EffectsLiver and kidney effects, reproductive toxicity, immune system effects, and potential cancer risk. EPA Limit10 ppt MCL Common SourcesFluoropolymer manufacturing (used as PFOA replacement), industrial wastewater discharge. | ND | 0.01 | µg/L | PFAS | Not Detected |
| lithium LithiumInorganic A naturally occurring alkali metal found in groundwater. Monitored under UCMR 5 to assess occurrence in drinking water. Health EffectsKidney effects at high doses. Low-level exposure effects under study; some research suggests neurological effects. EPA LimitNo MCL (monitoring only under UCMR 5) Common SourcesNatural mineral deposits, geothermal water, and industrial discharge. | 10.000 | HI | µg/L | PFAS | Detected |
| NEtFOSAA | ND | HI | µg/L | PFAS | Not Detected |
| NFDHA | ND | HI | µg/L | PFAS | Not Detected |
| NMeFOSAA | ND | HI | µg/L | PFAS | Not Detected |
| PFBA PFBAPFAS One of the shortest-chain PFAS compounds. Very mobile in water and difficult to remove with standard filtration. Health EffectsThyroid effects, potential developmental toxicity. Shorter half-life in body than long-chain PFAS. EPA LimitNo individual MCL (not yet regulated) Common SourcesDegradation of longer-chain PFAS, industrial discharge, and firefighting foam. | ND | HI | µg/L | PFAS | Not Detected |
| PFBS PFBSPFAS A short-chain PFAS used as a replacement for PFOS. While it clears the body faster than long-chain PFAS, it still persists in the environment. Health EffectsThyroid effects, reproductive and developmental toxicity, kidney effects. EPA LimitPart of Hazard Index (1.0) Common SourcesIndustrial discharge, firefighting foam, and as a replacement chemical in manufacturing. | ND | HI | µg/L | PFAS | Not Detected |
| PFDA | ND | HI | µg/L | PFAS | Not Detected |
| PFDoA | ND | HI | µg/L | PFAS | Not Detected |
| PFEESA | ND | HI | µg/L | PFAS | Not Detected |
| PFHpA PFHpAPFAS A medium-chain PFAS compound found in various environmental samples. Less studied than PFOA/PFOS but still considered a contaminant of concern. Health EffectsLiver effects, potential developmental toxicity, and endocrine disruption. EPA LimitPart of Hazard Index (1.0) Common SourcesDegradation of longer-chain PFAS, industrial discharge, and contaminated water sources. | ND | HI | µg/L | PFAS | Not Detected |
| PFHpS | ND | HI | µg/L | PFAS | Not Detected |
| PFHxA PFHxAPFAS A short-chain PFAS replacement chemical widely used after manufacturers phased out longer-chain PFAS. Very commonly detected in water. Health EffectsLiver and kidney effects, potential thyroid disruption. Considered less toxic than long-chain PFAS but still persistent. EPA LimitNo individual MCL (not yet regulated) Common SourcesIndustrial processes, firefighting foam (AFFF), food packaging, and textile treatment. | ND | HI | µg/L | PFAS | Not Detected |
| PFHxS PFHxSPFAS A medium-chain PFAS found in firefighting foam and consumer products. It has a long half-life in the human body, similar to long-chain PFAS. Health EffectsImmune system effects, thyroid disruption, and potential reproductive and developmental harm. EPA LimitPart of Hazard Index (1.0) Common SourcesFirefighting foam (AFFF), waterproof textiles, food packaging, and industrial discharge. | ND | HI | µg/L | PFAS | Not Detected |
| PFMBA | ND | HI | µg/L | PFAS | Not Detected |
| PFMPA | ND | HI | µg/L | PFAS | Not Detected |
| PFNA PFNAPFAS A long-chain PFAS compound used in manufacturing fluoropolymers. It bioaccumulates in the body and is very persistent in the environment. Health EffectsDevelopmental effects, liver toxicity, immune suppression, and potential cancer risk. EPA LimitPart of Hazard Index (1.0) Common SourcesFluoropolymer manufacturing, industrial emissions, and contaminated water sources. | ND | HI | µg/L | PFAS | Not Detected |
| PFOA PFOAPFAS A long-chain PFAS ("forever chemical") once widely used in nonstick coatings and firefighting foam. It persists in the body and environment for years. Health EffectsLinked to kidney and testicular cancer, thyroid disease, elevated cholesterol, and reproductive issues. EPA Limit4.0 ppt MCL Common SourcesIndustrial discharge, firefighting foam (AFFF), nonstick cookware manufacturing, and contaminated groundwater. | ND | 0.004 | µg/L | PFAS | Not Detected |
| PFOS PFOSPFAS A long-chain PFAS compound historically used in stain-resistant coatings and firefighting foam. One of the most studied and persistent PFAS chemicals. Health EffectsLiver damage, immune system suppression, thyroid disruption, increased cholesterol, and potential cancer risk. EPA Limit4.0 ppt MCL Common SourcesFirefighting foam (AFFF), industrial sites, stain-resistant fabric treatments, and contaminated groundwater. | ND | 0.004 | µg/L | PFAS | Not Detected |
| PFPeA PFPeAPFAS A short-chain PFAS compound commonly detected in drinking water. One of the most frequently found PFAS in UCMR 5 monitoring. Health EffectsLess studied than PFOA/PFOS. Potential liver and thyroid effects. Research is ongoing. EPA LimitNo individual MCL (not yet regulated) Common SourcesIndustrial discharge, firefighting foam degradation, and consumer products. | ND | HI | µg/L | PFAS | Not Detected |
| PFPeS | ND | HI | µg/L | PFAS | Not Detected |
| PFTA | ND | HI | µg/L | PFAS | Not Detected |
| PFTrDA | ND | HI | µg/L | PFAS | Not Detected |
| PFUnA | ND | HI | µg/L | PFAS | Not Detected |
Lead level trend (90th percentile)
See how Combined Locks compares by contaminant
Explore where Combined Locks ranks among all Wisconsin cities for specific contaminants.
Water source & infrastructure
Where Combined Locks's water comes from
Combined Locks purchases its water supply from a regional wholesale provider rather than treating raw water directly.
Water quality depends on both the wholesaler's treatment standards and the condition of Combined Locks's local distribution pipes and storage facilities.
Purchased water systems are common in suburban areas and smaller communities that lack the infrastructure for independent treatment.
The system is operated by local government ownership and serves approximately 3,609 people through 1 water system.
Water bodies near Combined Locks
Combined Locks is located near 2 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Combined Locks
| System Name | PWSID | Population | Source |
|---|---|---|---|
| COMBINED LOCKS WATERWORKS | WI4450409 | 3,609 | GWP |
How Combined Locks compares
Full Wisconsin rankings →Combined Locks's score of 77.7/100 is above the average of 65/100 among major Wisconsin cities. It outscores 6 of 10 nearby cities.
Nearby cities
View Wisconsin rankings →About Combined Locks, WI
Learn more about your water
Guides and resources related to Combined Locks's water quality findings.
Explore water quality across Outagamie
Frequently asked questions
Is Combined Locks, WI tap water safe to drink?
Combined Locks's water quality earned a grade of B (77.7/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #292 out of 446 cities tested in Wisconsin.
What contaminants are in Combined Locks's water?
Lead was measured at 0.0 ppb (90th percentile). 1 PFAS compound was detected. 8 violations are on record.
How is Combined Locks'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 Combined Locks?
PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.
Where does Combined Locks's water come from?
Combined Locks's water is sourced from Purchased ground water. The city has 1 water system serving approximately 3,609 residents.
What health violations has Combined Locks's water system had?
Combined Locks has 1 health-based violation on record. The most recent violation was recorded in October 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 5 violations remain unresolved.
Is Combined Locks's groundwater at risk of contamination?
Combined Locks 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 8 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 Combined Locks's water compare to other cities?
Combined Locks ranks #292 out of 446 cities in Wisconsin (better than 35% of state cities) and #8912 out of 15744 cities nationally (43th percentile). The grade of B reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.