Is Fort Benton, MT 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 ↓
81.2/100
waterverge.com Fort Benton, MT — Water Quality Report
Fort Benton's drinking water received a grade of B+ (81.2 out of 100), indicating good water quality. The city's 2 water systems serve approximately 1,550 residents using groundwater.
Lead levels were measured at 2.0 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 37 violations on record, including 1 health-based violation. 10 remain unresolved.
What to know about Fort Benton's water
Fort Benton ranks #34 out of 115 cities in Montana for water quality, placing it mid-range in the state.
Fort Benton 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, Fort Benton may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Fort Benton, MT water safe to drink?
Fort Benton's drinking water has significant quality concerns based on EPA testing data. With a grade of B+ (81.2/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 1,550 residents using groundwater (wells).
Recent water quality updates for Fort Benton
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Fort Benton's water quality assessment. Grade: B+ (81.2/100).
Contaminants: E. COLI.
Contaminants: TTHM, Total Haloacetic Acids (HAA5).
Contaminants: Consumer Confidence Rule.
Federal disaster declaration (FEMA DR-4127). Flood event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-3253). Hurricane event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Fort Benton'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
Fort Benton's water system has 37 total violations on record, including 1 health-based violation. 10 remain unresolved. 5 violations were issued in the last 5 years.
Flood & environmental risk
Chouteau County has experienced 3 federally declared disasters since 1986. 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 Missouri River At Fort Benton, Marias River Near Loma.
Where does Fort Benton's water come from?
Fort Benton's drinking water comes from groundwater (wells), supplied by 2 water systems serving approximately 1,550 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Missouri River At Fort Benton (river), Marias River Near Loma (river).
What Fort Benton residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Fort Benton'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.
Fort Benton'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
Drought conditions
D3 — extreme droughtChouteau County is currently in D3 (extreme 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
Chouteau County has experienced 3 federally declared disasters since 1986. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Recommended water filters
Based on contaminants detected in Fort Benton'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. | 2.0 | 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. | 1.61 | 1.3 | mg/L | Inorganic | Over Limit |
Lead level trend (90th percentile)
Copper level trend (90th percentile)
See how Fort Benton compares by contaminant
Explore where Fort Benton ranks among all Montana cities for specific contaminants.
Water source & infrastructure
Where Fort Benton's water comes from
Fort Benton'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 1,550 people through 2 water systems.
Water bodies near Fort Benton
Fort Benton is located near 2 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Fort Benton
| System Name | PWSID | Population | Source |
|---|---|---|---|
| FORT BENTON CITY OF | MT0000216 | 1,500 | GW |
| HAWARDEN SQUARE BUTTE WATER | MT0003522 | 50 | GWP |
How Fort Benton compares
Full Montana rankings →Fort Benton's score of 81.2/100 is above the average of 45/100 among major Montana cities. It outscores 9 of 10 nearby cities.
Nearby cities
View Montana rankings →About Fort Benton, MT
Wikipedia →Fort Benton is a city in and the county seat of Chouteau County, Montana, United States. Established in 1846, Fort Benton is the oldest continuously occupied settlement in Montana. Fort Benton was the most upstream navigable port on the Mississippi River System, and is considered "the world’s innermost port".
Learn more about your water
Guides and resources related to Fort Benton's water quality findings.
Explore water quality across Chouteau
Frequently asked questions
Is Fort Benton, MT tap water safe to drink?
Fort Benton's water quality earned a grade of B+ (81.2/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #34 out of 115 cities tested in Montana.
What contaminants are in Fort Benton's water?
Lead was measured at 2.0 ppb (90th percentile). 37 violations are on record.
How is Fort Benton'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 Fort Benton?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Fort Benton's water come from?
Fort Benton's water is sourced from Groundwater. The city has 2 water systems serving approximately 1,550 residents.
What health violations has Fort Benton's water system had?
Fort Benton has 1 health-based violation on record. The most recent violation was recorded in August 2023. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 10 violations remain unresolved.
Is Fort Benton's groundwater at risk of contamination?
Fort Benton 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 37 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 Fort Benton's water compare to other cities?
Fort Benton ranks #34 out of 115 cities in Montana (better than 70% of state cities) and #7565 out of 15744 cities nationally (52th percentile). The grade of B+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.