Is Cuba City, WI Tap Water Safe to Drink?
Graded B — but Copper was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓
79.2/100
waterverge.com Cuba City, WI — Water Quality Report
Cuba City's drinking water received a grade of B (79.2 out of 100), indicating good water quality. The city's 1 water system serves approximately 2,141 residents using groundwater.
Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program.
The system has 10 violations on record, including 4 health-based violations. 5 remain unresolved.
What to know about Cuba City's water
Cuba City ranks #273 out of 446 cities in Wisconsin for water quality, placing it below average in the state.
Cuba City relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.
As a small community water system, Cuba City may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Cuba City, WI water safe to drink?
Cuba City's drinking water has significant quality concerns based on EPA testing data. With a grade of B (79.2/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 2,141 residents using groundwater (wells).
Recent water quality updates for Cuba City
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Cuba City's water quality assessment. Grade: B (79.2/100).
1 health-based. Contaminants: LEAD AND COPPER RULE REVISIONS, Public Notice.
Contaminants: Groundwater Rule.
Contaminants: Coliform (TCR).
Federal disaster declaration (FEMA DR-3249). Hurricane event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-1369). Flood event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Cuba City's water supply.
Well within EPA limits.
Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.
Violation history
Cuba City's water system has 10 total violations on record, including 4 health-based violations. 5 remain unresolved. 2 violations were issued in the last 5 years.
Flood & environmental risk
Grant County has experienced 5 federally declared disasters since 1969. 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 Sinsinawa River.
Where does Cuba City's water come from?
Cuba City's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 2,141 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Sinsinawa River (river).
What Cuba City residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Cuba City'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.
Cuba City'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 ↓Violation summary
Violations & advisories
Top industrial polluters within 10 miles of Cuba City
Industrial polluters nearby
Reported releases to surface water by facilities near Cuba City, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
PRAIRIE FARMS WHITE HILL CHEESE SHULLSBURG, WI53586 | — | — | 9.9 mi |
SAFE FOOD CHEMICAL INNOVATIONS-KIELER KIELER, WI53812 | — | — | 8.8 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Flood & disaster history
Grant County has experienced 5 federally declared disasters since 1969. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Recommended water filters
Based on contaminants detected in Cuba City'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 |
| Copper (90th percentile) CopperInorganic A metal that enters drinking water mainly through corrosion of copper plumbing. Small amounts are essential for health, but excess levels are harmful. Health EffectsGastrointestinal distress (nausea, vomiting, diarrhea) at short-term high levels; liver and kidney damage from long-term exposure. EPA Limit1.3 mg/L action level Common SourcesCorrosion of copper household plumbing, erosion of natural deposits. | 2.80 | 1.3 | mg/L | Inorganic | Over Limit |
Lead level trend (90th percentile)
Copper level (90th percentile)
Latest reading: 2.800 mg/L (1999)
EPA action level: 1.3 mg/L
See how Cuba City compares by contaminant
Explore where Cuba City ranks among all Wisconsin cities for specific contaminants.
Water source & infrastructure
Where Cuba City's water comes from
Cuba City's drinking water is drawn from underground aquifers through wells.
Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.
Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.
The system is operated by local government ownership and serves approximately 2,141 people through 1 water system.
Water bodies near Cuba City
Cuba City is located near 1 notable water body. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Cuba City
| System Name | PWSID | Population | Source |
|---|---|---|---|
| CUBA CITY WATERWORKS | WI1220092 | 2,141 | GW |
How Cuba City compares
Full Wisconsin rankings →Cuba City's score of 79.2/100 is above the average of 65/100 among major Wisconsin cities. It outscores 7 of 10 nearby cities.
Nearby cities
View Wisconsin rankings →About Cuba City, WI
Learn more about your water
Guides and resources related to Cuba City's water quality findings.
Explore water quality across Grant
Frequently asked questions
Is Cuba City, WI tap water safe to drink?
Cuba City's water quality earned a grade of B (79.2/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #273 out of 446 cities tested in Wisconsin.
What contaminants are in Cuba City's water?
Lead was measured at 0.0 ppb (90th percentile). 10 violations are on record.
How is Cuba City'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 Cuba City?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Cuba City's water come from?
Cuba City's water is sourced from Groundwater. The city has 1 water system serving approximately 2,141 residents.
What health violations has Cuba City's water system had?
Cuba City has 4 health-based violations 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 Cuba City's groundwater at risk of contamination?
Cuba City 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 10 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 Cuba City's water compare to other cities?
Cuba City ranks #273 out of 446 cities in Wisconsin (better than 39% of state cities) and #8345 out of 15744 cities nationally (47th percentile). The grade of B reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Cuba City's small water system affect quality?
Cuba City's system serves approximately 2,141 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 10 violations on record.