Is Dillon, CO Tap Water Safe to Drink?
Graded C+ — but Copper was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓
67.8/100
waterverge.com Dillon, CO — Water Quality Report
Dillon's drinking water received a grade of C+ (67.8 out of 100), indicating fair water quality. The city's 4 water systems serve approximately 9,018 residents using surface water.
Lead levels were measured at 8.0 ppb (90th percentile), which is within EPA limits but above recommended levels. This system has not yet been tested for PFAS under the EPA UCMR 5 program.
The system has 34 violations on record, including 0 health-based violations. 9 remain unresolved.
What to know about Dillon's water
Dillon ranks #131 out of 246 cities in Colorado 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.
While lead levels are within EPA limits, they are above the recommended 5 ppb threshold that health organizations consider ideal. A point-of-use filter adds an extra layer of protection.
The system has seen 17 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Dillon, CO water safe to drink?
Dillon's drinking water has significant quality concerns based on EPA testing data. With a grade of C+ (67.8/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 4 water systems serve approximately 9,018 residents using surface water (rivers, lakes, or reservoirs).
Recent water quality updates for Dillon
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Dillon's water quality assessment. Grade: C+ (67.8/100).
Contaminants: Surface Water Treatment Rule.
Contaminants: Chlorine, Interim Enhanced Surface Water Treatment Rule.
Contaminants: Interim Enhanced Surface Water Treatment Rule.
Federal disaster declaration (FEMA DR-3224). Coastal Storm event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Dillon's water supply.
Within EPA limits but above the American Academy of Pediatrics recommended level of 1 ppb. An NSF 53-certified filter provides additional protection.
Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.
Violation history
Dillon's water system has 34 total violations on record, including 0 health-based violations. 9 remain unresolved. 17 violations were issued in the last 5 years.
Flood & environmental risk
Summit County has experienced 1 federally declared disaster since 2005. 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 Bobtail Creek, Williams Fork Below Steelman Creek, Co., Blue River, Snake River, Keystone Gulch.
Where does Dillon's water come from?
Dillon's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 4 water systems serving approximately 9,018 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include Bobtail Creek (river), Williams Fork Below Steelman Creek, Co. (river), Blue River (river), Snake River (river), Keystone Gulch (river).
What Dillon residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Dillon'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.
Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.
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 Dillon
Industrial polluters nearby
Reported releases to surface water by facilities near Dillon, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
PEAK SILVERTHORNE BATCH PLANT SILVERTHORNE, CO80498 | — | — | 6.2 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Drought conditions
D4 — exceptional droughtSummit County is currently in D4 (exceptional drought) per the U.S. Drought Monitor (week of May 5, 2026). 100.0% of the county is in D4 (exceptional) drought. 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
Summit County has experienced 1 federally declared disaster since 2005. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Recommended water filters
Based on contaminants detected in Dillon'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. | 8.0 | 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. | 1.72 | 1.3 | mg/L | Inorganic | Over Limit |
Lead level trend (90th percentile)
Copper level trend (90th percentile)
See how Dillon compares by contaminant
Explore where Dillon ranks among all Colorado cities for specific contaminants.
Water source & infrastructure
Where Dillon's water comes from
Dillon'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 9,018 people through 4 water systems.
Water bodies near Dillon
Dillon is located near 5 notable water bodies. As a surface water system, these water bodies may directly influence the city's drinking water supply.
Water systems serving Dillon
| System Name | PWSID | Population | Source |
|---|---|---|---|
| DILLON TOWN OF | CO0159035 | 3,254 | SW |
| DILLON VALLEY DISTRICT | CO0159040 | 3,063 | SW |
| EAST DILLON WD | CO0159045 | 2,501 | GU |
| HAMILTON CREEK MD | CO0159063 | 200 | SW |
How Dillon compares
Full Colorado rankings →Dillon's score of 67.8/100 is above the average of 45/100 among major Colorado cities. It outscores 9 of 10 nearby cities.
Nearby cities
View Colorado rankings →About Dillon, CO
Learn more about your water
Guides and resources related to Dillon's water quality findings.
Explore water quality across Summit
Frequently asked questions
Is Dillon, CO tap water safe to drink?
Dillon's water quality earned a grade of C+ (67.8/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #131 out of 246 cities tested in Colorado.
What contaminants are in Dillon's water?
Lead was measured at 8.0 ppb (90th percentile). 34 violations are on record.
How is Dillon'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 Dillon?
While lead levels are within EPA limits, a filter adds extra protection. Based on current data, basic filtration should suffice for additional peace of mind.
Where does Dillon's water come from?
Dillon's water is sourced from Surface water. The city has 4 water systems serving approximately 9,018 residents.
How does Dillon's water compare to other cities?
Dillon ranks #131 out of 246 cities in Colorado (better than 47% of state cities) and #11174 out of 15744 cities nationally (29th percentile). The grade of C+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.