01The verdict: is Deer Lodge water safe?
Deer Lodge's drinking water has significant quality concerns based on EPA testing data. With a grade of D (47.5/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 5,000 residents using groundwater (wells).
13 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 2.0 ppb — beneath the 15 ppb federal action level and under the 5 ppb watch threshold.
See the trend ↓99 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 ↓Deer Lodge's drinking water received a grade of D (47.5 out of 100), indicating poor water quality. The city's 2 water systems serve approximately 5,000 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 162 violations on record, including 7 health-based violations. 13 remain unresolved.
Deer Lodge ranks #81 out of 110 cities in Montana for water quality, placing it below average in the state. Deer Lodge 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. The system has seen 99 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
02What's in Deer Lodge's water
Every contaminant flagged in Deer Lodge, 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. | 2.0 | 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
03Deer Lodge'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 162 violations on record, including 7 health-based violations. 13 remain unresolved.
4 of the last ten years were clean. The numbered years had EPA violations — red when any were health-based, amber when they were paperwork or missed-testing issues.
▼ Down 2 ppb since 1992. Latest reading: 2 ppb (2024) — 13% of the action level. Sampled at higher-risk homes (90th percentile).
04Where Deer Lodge's water comes from
Deer Lodge's drinking water is drawn from underground aquifers through wells.
Groundwater
Underground aquifers reached by wells — naturally filtered, but can carry minerals like arsenic and nitrate.
Local treatment
Groundwater generally needs less treatment — typically disinfection and, where needed, mineral removal.
2 systems
2 water systems, operated under local government ownership.
5,000 people
Residents served across Deer Lodge's service area.
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 5,000 people through 2 water systems.
| System name | PWSID | Population | Source |
|---|---|---|---|
| DEER LODGE CITY OF | MT0000197 | 2,900 | Groundwater |
| MONTANA STATE PRISON | MT0000198 | 2,100 | Groundwater |
Water bodies near Deer Lodge
These water bodies shape the regional watershed and can indirectly affect groundwater quality.
05Pressure on Deer Lodge'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
5 federal disaster declarations on record for Powell County. Flooding and severe storms can overwhelm treatment plants, cause sewage overflows, and push runoff into supplies.
Drought
Powell County is in D1 (moderate drought) per the U.S. Drought Monitor (week of Jul 2026). Drought can raise disinfection-byproduct levels and taste/odor issues as utilities draw from lower reservoirs.
06How Deer Lodge compares
Scores for nearby Montana cities on one line, with the average marked.
dashed line = Montana average (48/100)
Deer Lodge scores 47.5/100 — 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
Compare all cities in the county — grades, violations, and contaminant data side by side.→
07What to do at home
Steps matched to what testing actually found in Deer Lodge's water — not generic advice.
A basic carbon filter still helps
Deer Lodge'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 Deer Lodge alerts
This area has a history of flood declarations — after severe weather, watch for boil-water advisories from the utility, and check the live alerts on this page.
All water alerts →Frequently asked questions
Is Deer Lodge, MT tap water safe to drink?
Deer Lodge's water quality earned a grade of D (47.5/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #81 out of 110 cities tested in Montana.
What contaminants are in Deer Lodge's water?
Lead was measured at 2.0 ppb (90th percentile). 162 violations are on record.
How is Deer Lodge'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 Deer Lodge?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Deer Lodge's water come from?
Deer Lodge's water is sourced from Groundwater. The city has 2 water systems serving approximately 5,000 residents.
What health violations has Deer Lodge's water system had?
Deer Lodge has 7 health-based violations on record. The most recent violation was recorded in October 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 13 violations remain unresolved.
Is Deer Lodge's groundwater at risk of contamination?
Deer Lodge 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 162 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 Deer Lodge's water compare to other cities?
Deer Lodge ranks #81 out of 110 cities in Montana (better than 26% of state cities) and #13337 out of 15382 cities nationally (13th percentile). The grade of D reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.