Is Tioga, ND Tap Water Safe to Drink?
Graded A, with 2 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
90.4/100
waterverge.com Tioga, ND — Water Quality Report
Tioga's drinking water received a grade of A (90.4 out of 100), indicating excellent water quality. The city's 2 water systems serve approximately 3,205 residents using purchased surface water.
Lead levels were measured at 1.7 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 7 violations on record, including 0 health-based violations. 2 remain unresolved.
What to know about Tioga's water
Tioga ranks #32 out of 103 cities in North Dakota for water quality, placing it mid-range in the state.
The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection.
As a small community water system, Tioga may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Tioga, ND water safe to drink?
Tioga's tap water meets most EPA standards but has areas that warrant attention. With a grade of A (90.4/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 2 water systems serve approximately 3,205 residents using surface water (rivers, lakes, or reservoirs).
Recent water quality updates for Tioga
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Tioga's water quality assessment. Grade: A (90.4/100).
Contaminants: Lead and Copper Rule.
Federal disaster declaration (FEMA DR-1981). Flood event — may have impacted local water infrastructure.
Contaminants: Coliform (TCR).
Contaminants: Chlorine.
Federal disaster declaration (FEMA DR-3247). Coastal Storm event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Tioga's water supply.
Well within EPA limits.
Violation history
Tioga's water system has 7 total violations on record, including 0 health-based violations. 2 remain unresolved.
Flood & environmental risk
Williams County has experienced 8 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.
Where does Tioga's water come from?
Tioga's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 2 water systems serving approximately 3,205 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment.
What Tioga residents can do
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.
Tioga'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 Tioga
Industrial polluters nearby
Reported releases to surface water by facilities near Tioga, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
WHITING OIL & GAS CORP LLC - RAY GAS PLANT RAY, ND58849 | — | — | 8.6 mi |
HESS TIOGA GAS PLANT LLC TIOGA, ND58852 | — | — | 1.4 mi |
NESSON GAS PLANT TIOGA, ND58852 | — | — | 5.2 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Drought conditions
D1 — moderate droughtWilliams County is currently in D1 (moderate drought) per the U.S. Drought Monitor (week of May 5, 2026). Drought can elevate disinfection-byproduct (TTHM/HAA5) levels and taste/odor issues as utilities draw from lower reservoirs.
Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.
Flood & disaster history
Williams County has experienced 8 federally declared disasters since 1969. 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. | 1.7 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Tioga compares by contaminant
Explore where Tioga ranks among all North Dakota cities for specific contaminants.
Water source & infrastructure
Where Tioga's water comes from
Tioga's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.
Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards.
These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge.
The system is operated by local government ownership and serves approximately 3,205 people through 2 water systems.
Water systems serving Tioga
| System Name | PWSID | Population | Source |
|---|---|---|---|
| TIOGA CITY OF | ND5300936 | 2,202 | SWP |
| R & T WATER SYSTEM | ND5301152 | 1,003 | SWP |
How Tioga compares
Full North Dakota rankings →Tioga's score of 90.4/100 is above the average of 82/100 among major North Dakota cities. It outscores 6 of 10 nearby cities.
Nearby cities
View North Dakota rankings →About Tioga, ND
Learn more about your water
Guides and resources related to Tioga's water quality findings.
Explore water quality across Williams
Frequently asked questions
Is Tioga, ND tap water safe to drink?
Tioga's water quality earned a grade of A (90.4/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #32 out of 103 cities tested in North Dakota.
What contaminants are in Tioga's water?
Lead was measured at 1.7 ppb (90th percentile). 7 violations are on record.
How is Tioga'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 Tioga?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Tioga's water come from?
Tioga's water is sourced from Purchased surface water. The city has 2 water systems serving approximately 3,205 residents.
How does Tioga's water compare to other cities?
Tioga ranks #32 out of 103 cities in North Dakota (better than 69% of state cities) and #2226 out of 15744 cities nationally (86th percentile). The grade of A reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.