Is Lodi, WI Tap Water Safe to Drink?
Graded B-, with 25 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
70.1/100
waterverge.com Lodi, WI — Water Quality Report
Lodi's drinking water received a grade of B- (70.1 out of 100), indicating fair water quality. The city's 4 water systems serve approximately 5,866 residents using groundwater.
Lead levels were measured at 0.5 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 65 violations on record, including 20 health-based violations. 25 remain unresolved.
What to know about Lodi's water
Lodi ranks #347 out of 446 cities in Wisconsin for water quality, placing it among the lowest-rated in the state.
Lodi 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.
The system has seen 7 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Lodi, WI water safe to drink?
Lodi's drinking water has significant quality concerns based on EPA testing data. With a grade of B- (70.1/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 4 water systems serve approximately 5,866 residents using groundwater (wells).
Recent water quality updates for Lodi
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Lodi's water quality assessment. Grade: B- (70.1/100).
1 health-based. Contaminants: LEAD AND COPPER RULE REVISIONS, Public Notice.
1 health-based. Contaminants: Lead and Copper Rule.
1 health-based. Contaminants: Arsenic.
Federal disaster declaration (FEMA DR-3249). Hurricane event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-496). Flood event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Lodi's water supply.
Well within EPA limits.
Violation history
Lodi's water system has 65 total violations on record, including 20 health-based violations. 25 remain unresolved. 7 violations were issued in the last 5 years.
Flood & environmental risk
Columbia County has experienced 2 federally declared disasters since 1976. 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 Sixmile Creek.
Where does Lodi's water come from?
Lodi's drinking water comes from groundwater (wells), supplied by 4 water systems serving approximately 5,866 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Sixmile Creek (river).
What Lodi residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Lodi'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.
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 Lodi
Industrial polluters nearby
Reported releases to surface water by facilities near Lodi, ranked by pounds discharged annually.
Total reported releases to surface water: 88 lbs
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
MILWAUKEE VALVE CO LLC PRAIRIE DU SAC, WI53578 | Copper | 88 | 9.7 mi |
COATING PLACE INC. SAUK CITY SAUK CITY, WI53583 | — | — | 10.0 mi |
NORD GEAR CORP WAUNAKEE, WI53597 | — | — | 10.0 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Flood & disaster history
Columbia County has experienced 2 federally declared disasters since 1976. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
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. | 0.5 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Lodi compares by contaminant
Explore where Lodi ranks among all Wisconsin cities for specific contaminants.
Water source & infrastructure
Where Lodi's water comes from
Lodi'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 5,866 people through 4 water systems.
Water bodies near Lodi
Lodi is located near 1 notable water body. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Lodi
| System Name | PWSID | Population | Source |
|---|---|---|---|
| LODI WATERWORKS | WI1110100 | 3,146 | GW |
| HARMONY GROVE SAN DIST | WI1110101 | 1,950 | GW |
| CRYSTAL LAKE RV RESORT LLC | WI1110066 | 725 | GW |
| HARMONY MOBILE MANOR | WI1110065 | 45 | GW |
How Lodi compares
Full Wisconsin rankings →Lodi's score of 70.1/100 is above the average of 65/100 among major Wisconsin cities. It outscores 6 of 10 nearby cities.
Nearby cities
View Wisconsin rankings →About Lodi, WI
Learn more about your water
Guides and resources related to Lodi's water quality findings.
Explore water quality across Columbia
Frequently asked questions
Is Lodi, WI tap water safe to drink?
Lodi's water quality earned a grade of B- (70.1/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #347 out of 446 cities tested in Wisconsin.
What contaminants are in Lodi's water?
Lead was measured at 0.5 ppb (90th percentile). 65 violations are on record.
How is Lodi'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 Lodi?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Lodi's water come from?
Lodi's water is sourced from Groundwater. The city has 4 water systems serving approximately 5,866 residents.
What health violations has Lodi's water system had?
Lodi has 20 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. 25 violations remain unresolved.
Is Lodi's groundwater at risk of contamination?
Lodi 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 65 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 Lodi's water compare to other cities?
Lodi ranks #347 out of 446 cities in Wisconsin (better than 22% of state cities) and #10804 out of 15744 cities nationally (31th percentile). The grade of B- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.