Is Preston, MN Tap Water Safe to Drink?
Graded B+, with 6 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
84/100
waterverge.com Preston, MN — Water Quality Report
Preston's drinking water received a grade of B+ (84 out of 100), indicating good water quality. The city's 2 water systems serve approximately 1,372 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 25 violations on record, including 0 health-based violations. 6 remain unresolved.
What to know about Preston's water
Preston ranks #375 out of 466 cities in Minnesota for water quality, placing it among the lowest-rated in the state.
Preston 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, Preston may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
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 Preston, MN water safe to drink?
Preston's drinking water has significant quality concerns based on EPA testing data. With a grade of B+ (84/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 1,372 residents using groundwater (wells).
Recent water quality updates for Preston
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Preston's water quality assessment. Grade: B+ (84/100).
Contaminants: Revised Total Coliform Rule.
Contaminants: LEAD AND COPPER RULE REVISIONS.
Contaminants: Revised Total Coliform Rule.
Federal disaster declaration (FEMA DR-4797). Flood event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-4442). Flood event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Preston's water supply.
Well within EPA limits.
Violation history
Preston's water system has 25 total violations on record, including 0 health-based violations. 6 remain unresolved. 7 violations were issued in the last 5 years.
Flood & environmental risk
Fillmore County has experienced 7 federally declared disasters since 1965. 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 Root River.
Where does Preston's water come from?
Preston's drinking water comes from groundwater (wells), supplied by 2 water systems serving approximately 1,372 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Root River (river).
What Preston residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Preston'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.
Preston'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 Preston
Industrial polluters nearby
Reported releases to surface water by facilities near Preston, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
POET BIOREFNING - PRESTON LLC PRESTON, MN55965 | — | — | 1.1 mi |
PRESTON PROTEIN PRODUCTS PRESTON, MN55965 | — | — | 0.3 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Flood & disaster history
Fillmore County has experienced 7 federally declared disasters since 1965. 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. | 0.0 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Preston compares by contaminant
Explore where Preston ranks among all Minnesota cities for specific contaminants.
Water source & infrastructure
Where Preston's water comes from
Preston'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 1,372 people through 2 water systems.
Water bodies near Preston
Preston is located near 1 notable water body. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Preston
| System Name | PWSID | Population | Source |
|---|---|---|---|
| Preston | MN1230010 | 1,322 | GW |
| Greenleafton | MN1230004 | 50 | GW |
How Preston compares
Full Minnesota rankings →Preston's score of 84/100 is on par with the average of 82/100 among major Minnesota cities. It outscores 5 of 10 nearby cities.
Nearby cities
View Minnesota rankings →About Preston, MN
Wikipedia →Preston is a city in and the county seat of Fillmore County, Minnesota, United States. As of the 2020 census, Preston had a population of 1,322. The Root River runs through it, and Mystery Cave State Park is nearby. It bills itself as "America's Trout Capital," with a 20-foot trout placed along Minnesota State Highway 16.
Learn more about your water
Guides and resources related to Preston's water quality findings.
Explore water quality across Fillmore
Frequently asked questions
Is Preston, MN tap water safe to drink?
Preston's water quality earned a grade of B+ (84/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #375 out of 466 cities tested in Minnesota.
What contaminants are in Preston's water?
Lead was measured at 0.0 ppb (90th percentile). 25 violations are on record.
How is Preston'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 Preston?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Preston's water come from?
Preston's water is sourced from Groundwater. The city has 2 water systems serving approximately 1,372 residents.
Is Preston's groundwater at risk of contamination?
Preston 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 25 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 Preston's water compare to other cities?
Preston ranks #375 out of 466 cities in Minnesota (better than 20% of state cities) and #6156 out of 15744 cities nationally (61th percentile). The grade of B+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.