01The verdict: is Crow Agency water safe?
Crow Agency's drinking water has significant quality concerns based on EPA testing data. With a grade of D (49/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 3 water systems serve approximately 1,967 residents using surface water (rivers, lakes, or reservoirs).
43 unresolved violations on record
EPA records show open compliance items for this system. Most are administrative, but unresolved items are worth watching.
See what was cited ↓Lead is well under the limit
90th-percentile lead is 0.0 ppb — beneath the 15 ppb federal action level and under the 5 ppb watch threshold.
See the trend ↓170 violations in the last five years
Recent compliance history is the best predictor of future problems — the year-by-year record is below.
See the record ↓Crow Agency's drinking water received a grade of D (49 out of 100), indicating poor water quality. The city's 3 water systems serve approximately 1,967 residents using surface water.
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 621 violations on record, including 43 health-based violations. 43 remain unresolved.
Crow Agency ranks #80 out of 110 cities in Montana for water quality, placing it below average 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, Crow Agency may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities. The system has seen 170 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
02What's in Crow Agency's water
Every contaminant flagged in Crow Agency, on one shared scale: distance to its own legal limit. The red line is the limit — anything past it is out of compliance, and the closer a bar gets, the less headroom the system has.
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 |
Cities ranked by 90th-percentile lead PF PFAS in Montana
Cities ranked by compounds detected Cu Copper in Montana
Cities ranked by 90th-percentile copper
03Crow Agency's ten-year track record
Each box is one year. A green check means no EPA violations; a numbered badge counts that year's violations — red if any were health-based, amber if they were monitoring or paperwork issues. The system has 621 violations on record, including 43 health-based violations. 43 remain unresolved.
1 of the last ten years was clean. The numbered years had EPA violations — red when any were health-based, amber when they were paperwork or missed-testing issues.
▼ Down 4 ppb since 1999. Latest reading: 1 ppb (2025) — 7% of the action level. Sampled at higher-risk homes (90th percentile).
04Where Crow Agency's water comes from
Crow Agency's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.
Surface Water
Rivers, lakes, or reservoirs — more exposed to runoff, agriculture, and seasonal swings than groundwater.
Local treatment
Multi-barrier treatment: coagulation, sedimentation, filtration, and disinfection to meet EPA standards.
3 systems
3 water systems, operated under federal ownership.
1,967 people
Residents served across Crow Agency's service area.
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 federal ownership and serves approximately 1,967 people through 3 water systems.
| System name | PWSID | Population | Source |
|---|---|---|---|
| CROW AGENCY WATER SYSTEM | 083090011 | 1,300 | Surface Water |
| PRYOR WATER SYSTEM | 083090012 | 406 | Groundwater |
| WYOLA WATER SYSTEM | 083090014 | 261 | Groundwater |
Water bodies near Crow Agency
As a surface-water system, these water bodies may directly influence Crow Agency's drinking water supply.
05Pressure on Crow Agency's watershed
Outside forces that shape what reaches the treatment plant. None of these is a verdict on the tap by itself — but each adds pressure worth knowing about.
Flood & storm history
2 federal disaster declarations on record for Big Horn County. Flooding and severe storms can overwhelm treatment plants, cause sewage overflows, and push runoff into supplies.
06How Crow Agency compares
Scores for nearby Montana cities on one line, with the average marked.
dashed line = Montana average (48/100)
Crow Agency scores 49/100 — on par with the Montana average of 48/100. It outscores 8 of 10 nearby cities. Full Montana rankings →
39.6 / 100FMissoula, MT
42.6 / 100FBozeman, MT
43.4 / 100FGreat Falls, MT
34.5 / 100FKalispell, MT
40.1 / 100FHelena, MT
39.1 / 100
07What to do at home
Steps matched to what testing actually found in Crow Agency's water — not generic advice.
A basic carbon filter still helps
Crow Agency's water meets federal standards, but a simple carbon filter improves taste and adds a margin of safety against short-term issues.
Compare tested filters →Read your utility's annual report
Every utility must publish a yearly Consumer Confidence Report with its own testing results. It pairs well with the independent data on this page.
How to read a CCR →Watch for Crow Agency alerts
We refresh EPA data monthly and surface new violations, advisories, and boil-water notices for your county on this page.
All water alerts →Frequently asked questions
Is Crow Agency, MT tap water safe to drink?
Crow Agency's water quality earned a grade of D (49/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #80 out of 110 cities tested in Montana.
What contaminants are in Crow Agency's water?
Lead was measured at 0.0 ppb (90th percentile). 621 violations are on record.
How is Crow Agency'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 Crow Agency?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Crow Agency's water come from?
Crow Agency's water is sourced from Surface water. The city has 3 water systems serving approximately 1,967 residents.
What health violations has Crow Agency's water system had?
Crow Agency has 43 health-based violations on record. The most recent violation was recorded in December 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 43 violations remain unresolved.
How does Crow Agency's water compare to other cities?
Crow Agency ranks #80 out of 110 cities in Montana (better than 27% of state cities) and #13096 out of 15382 cities nationally (15th percentile). The grade of D reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.