Skip to main content
WaterSafeCheck
Official EPA SDWIS Verified ReportWater Quality & Testing GuideHistorical Record: No Recorded SDWIS Violations

ZIP Code 56701 Water Quality & Testing Report

Thief River Falls, MN · Pennington County County · Updated for 2026

Sahajul HaqueCompiled & verified by Sahajul Haque from official EPA SDWIS records
Public Health & Medical Notice: Drinking water quality data on this page reflects historical compliance records submitted under the Safe Drinking Water Act. This information does not constitute medical advice or a real-time safety guarantee. If you are pregnant, nursing, preparing infant formula, or immunocompromised, consult a healthcare provider. Boiling water kills biological pathogens, but does NOT remove chemical contaminants like lead, arsenic, or PFAS.
Quick EPA Verified Answer

Is Tap Water Safe to Drink in ZIP 56701 (Thief River Falls, MN)?

Caution / Filtration Recommended: Tap water in ZIP code 56701 (Thief River Falls, MN) has compliance concerns, earning an EPA Safety Grade of C (56/100) due to 1 health violation(s) and 7.0 ppb lead. While treated by Thief River Falls, residents are advised to use an NSF/ANSI 53 certified water filter for drinking and cooking.

Safety Score
C

Water Safety Grade

Fair — Some compliance concerns

Health Violations

1

Total Violations

5

Lead Risk

High

Contaminants

1

⚠

Active Water Quality Issues Detected

EPA records show 2 unresolved violations. Contact Thief River Falls for current status.

About Tap Water in ZIP Code 56701

Tap water in ZIP code 56701 (Thief River Falls, MN) is distributed by Thief River Falls (EPA ID: MN1570003), serving approximately 8,701 residents. Based on EPA Safe Drinking Water Act compliance records, this system receives a water safety grade of C with a composite quality score of 56/100.

Water System

Thief River Falls

EPA ID: MN1570003

Water Source

Surface Water

Population Served

8,701 residents

County

Pennington County County, Minnesota

🧪

Lead Levels in ZIP 56701

EPA action level: 15 ppb | Public health goal: 0 ppb

Lead Level: 7.0 ppb — Moderate

The 90th percentile lead level in 56701 is 7.0 ppb. This is below the EPA action level of 15 ppb, but above ideal health goals. Consider a certified lead-reducing filter.

Lead exposure risk in 56701 is rated High. EPA models estimate a 59% exposure probability based on housing and infrastructure age.

Lead Level (90th percentile)
7.00 ppb (0.007 mg/L)
Lead Exposure Risk Rating
High
Lead Exposure Probability

EPA model estimate based on housing age and infrastructure

59%
Note: Lead levels above are the 90th percentile from EPA monitoring — meaning 90% of samples were at or below this level. Even "undetected" tap water lead doesn't account for lead leaching from home plumbing. If your home was built before 1986, individual tap testing is recommended.
🪨

Water Hardness & Mineral Content

Grains per gallon (GPG) & Parts per million (PPM / mg/L)

Classification: Hard7.3 GPG · 124 mg/L

Water in ZIP 56701 is Hard (124 mg/L / 7.3 GPG). Residents may notice white mineral spots on glassware, reduced soap efficiency, and mineral scale on faucets and showerheads.

Recommendation: An ion-exchange water softener or descaler is recommended to prolong the life of water heaters, dishwashers, and plumbing.
Hardness (GPG)

Grains per gallon

7.3 GPG
Hardness (PPM / mg/L)

Parts per million CaCO3

124 mg/L
Appliance Scaling Risk
High / Severe

Official EPA SDWIS Database Entry

Utility: Thief River Falls · PWSID: MN1570003

Verify on EPA.gov
📋

Violation History

Past 5 years — EPA SDWIS data

Thief River Falls has recorded 1 health-based violation out of 5 total violations over the past 5 years. 2 violations remain unresolved in EPA tracking records.

Total Violations (5 yr)
5
Health-Based Violations
1
Unresolved Violations
2
Boil Water Advisories
0
Compliance Risk
Critical

Regulatory compliance risk for this utility is rated Critical based on past reporting and enforcement records.

⚗️

Contaminants Detected

Contaminants with health-based violations on record

EPA records identify 1 contaminant with health-based violations in the past 5 years: Fecal Coliform.

Fecal Coliform

⚖ Enforcement Actions

EPA or state regulators have issued 10 enforcement actions to address compliance lapses.
🌊

Water Source & Environmental Factors

Surface Water

This system draws water from lakes, rivers, or reservoirs. Surface water is treated to remove sediment, microorganisms, and chemical contaminants before reaching taps.

Water Source Type
Surface Water
EPA Radon Zone

Highest potential

Zone 1
Annual Flood Risk Cost

Estimated annual flood-related costs per property

$3
Energy Burden

% of household income spent on energy — indicator of older infrastructure

2.56%

EPA Radon Zone 1 — highest potential for radon in indoor air. Homeowners should test their home for radon and consider mitigation if levels exceed 4 pCi/L.

Water Quality Testing in ZIP 56701

Tap Water & Well Testing Recommendations

Residents in ZIP code 56701 served by Thief River Falls can test tap water or private well systems to verify water purity. Testing detects hidden contaminants before they impact family health.

Tap Water Testing Steps

  • 1.Conduct a certified lead check if your home was constructed before 1986.
  • 2.Use certified lab testing kits rather than uncalibrated test strips for regulated compliance.
  • 3.Sample water from both your kitchen faucet and water heater to compare line purity.

Private Well Testing Steps

  • •Test for Coliform bacteria and Nitrates annually.
  • •Test for heavy metals, radon, and PFAS every 3 years.
  • •Send samples to a state-certified drinking water laboratory recognized by Minnesota Department of Health.
Certified Lab Testing: Always use an EPA-certified drinking water laboratory in MN for formal legal or real estate compliance testing.

🛡 What Should You Do? — ZIP 56701 Recommendations

  • ⚠ Use a certified NSF/ANSI 53 filter for drinking and cooking water if you have young children
  • ⚠ Never give unfiltered tap water to infants in formula — use certified bottled or filtered water
  • ⚠ Request a copy of the Consumer Confidence Report to see what was detected and when
  • ⚠ Call the EPA Safe Drinking Water Hotline: 1-800-426-4791

Recommended Water Treatment Systems:

🏺

NSF 53 Lead Pitcher Filter

Specifically certified to reduce lead and copper at the tap.

Lead Filter Guide →
⚗️

NSF 58 Under-Sink RO System

Advanced filtration for PFAS, fluoride, nitrates, and organic chemicals.

RO System Guide →

Frequently Asked Questions — ZIP 56701 Water Quality

Is tap water safe to drink in ZIP code 56701?+
Tap water in 56701 (Thief River Falls, MN) meets major standards but has a grade of C due to minor past violations. Vulnerable populations may want to use a certified filter as a precaution.
How do I get my water tested in ZIP 56701 (Thief River Falls, MN)?+
To test water quality in ZIP 56701, you can order a certified drinking water test kit or send water samples to an EPA/NELAP certified laboratory in MN. Certified testing checks for lead, coliform bacteria, nitrates, hardness, and PFAS that standard test strips miss. Contact Minnesota Department of Health for a list of certified regional labs.
How hard is the tap water in 56701?+
Tap water in 56701 is classified as Hard with an estimated mineral hardness of 124 mg/L (7.3 GPG). An ion-exchange water softener or descaler is recommended to prolong the life of water heaters, dishwashers, and plumbing.
Should I test private well water in 56701?+
Yes. Unlike municipal systems, private wells in 56701 are not regulated by the EPA or local utilities. Private well owners should test their water annually for coliform bacteria and nitrates, and every 3 to 5 years for heavy metals (lead, arsenic) and volatile organic compounds.
What is the lead level in 56701 tap water?+
The 90th percentile lead level in 56701 is 7.0 ppb. The EPA action level is 15 ppb. This is below the EPA action level.
Is there an active boil water notice in 56701?+
There are currently no active boil water advisories on record for 56701. Water treatment systems are operating within normal parameters.
Who provides tap water to 56701?+
Tap water in ZIP code 56701 is provided by Thief River Falls (EPA ID: MN1570003), serving approximately 8,701 residents.
What water filter should I use in 56701?+
Based on water metrics for 56701, we recommend Reverse Osmosis (PFAS & Lead). Look for certifications such as NSF/ANSI 58 (Reverse Osmosis), NSF/ANSI 53 (Lead & VOCs), NSF/ANSI P473 (PFAS/PFOS).

Data Sources & Methodology

Water quality data for ZIP code 56701 is compiled from the EPA Safe Drinking Water Information System (SDWIS), EPA ECHO enforcement database, UCMR5 unregulated contaminant monitoring, and Consumer Confidence Reports filed by Thief River Falls. Safety scores are composite metrics derived from violation history, lead levels, enforcement actions, and infrastructure risk indicators. Data reflects a 5-year monitoring window. Last dataset update: 2024. View EPA source data →