State Hub
Colorado Water Quality
423
Utilities in database
7.1M
Residents served
0
With open violations
154
PFAS monitored
Quick Answer
Colorado public drinking water is served by 423 EPA-tracked water systems, providing service to approximately 7.1 million residents through public utilities. No open health-based violations are currently recorded across tracked systems in the EPA federal database. 154 systems have official PFAS monitoring records from the EPA UCMR 5 program (2023–2025). About 25% of CO residents use private wells, which fall outside federal utility compliance monitoring.
No open health-based violations are currently recorded in the EPA SDWIS database for Colorado's tracked water systems. Always verify with your utility's Consumer Confidence Report for annual test results.
Drinking Water in Colorado
Colorado has 423 community water systems serving approximately 7.1 million residents. Primary water sources include surface water. The most commonly reported contaminants include disinfection byproducts, lead, arsenic. 25% of Colorado residents rely on private wells. CDPHE holds primary enforcement authority under the Safe Drinking Water Act.
Safest Large Utilities
Colorado systems with no open health violations serving 10,000+ residents.
Utilities in Colorado
26–50 of 423Green Mountain Wsd
CO0130321 · 49,400 served
City of Northglenn
CO0101115 · 48,927 served
Southwest Metropolitan Wsd
CO0103723 · 48,648 served
Us Department of the Army Fort Carson
CO0221445 · 48,000 served
Bancroft Clover Wsd
CO0130133 · 44,000 served
Town of Erie
CO0162255 · 40,061 served
City of Golden
CO0130040 · 38,288 served
City of Canon City
CO0122100 · 34,800 served
Clifton Wd
CO0139180 · 34,500 served
City of Durango
CO0134150 · 33,787 served
City of Aspen
CO0149122 · 31,100 served
Arapahoe Cnty Wwwa
CO0203002 · 31,000 served
Bear Creek Wsd
CO0130138 · 30,000 served
Pueblo West Md
CO0151650 · 30,000 served
Cherokee Md
CO0121125 · 29,610 served
City of Lafayette
CO0107473 · 28,700 served
Town of Breckenridge
CO0159020 · 28,315 served
East Larimer County Wd
CO0135233 · 27,944 served
Town of Firestone
CO0162476 · 27,798 served
Widefield Wsd
CO0121900 · 27,640 served
Csu Main and West Housing Campus
CO0235184 · 27,375 served
Town of Johnstown
CO0162418 · 27,295 served
City of Grand Junction
CO0139321 · 26,000 served
Little Thompson Wd
CO0135477 · 25,654 served
City of Fountain
CO0121275 · 25,130 served
Key Contaminant Concerns in Colorado
These contaminants appear most frequently in Colorado utility records or pose elevated risk in this region based on EPA data.
Lead
Lead is a naturally occurring heavy metal that was widely used in plumbing infrastructure until it was banned for new installations in 1986. An estimated 9.2 million lead service lines still connect homes to public water mains across the United States, along with millions of homes with lead solder in their internal plumbing. Critically, a utility's water quality report can show zero detected lead at the treatment plant while your specific tap still delivers elevated lead — because the contamination happens inside the distribution system and your home's plumbing, not at the source.
EPA limit: 15 ppb (action level)
DBPs
When utilities add chlorine to water to kill pathogens, it reacts with dissolved organic matter — leaves, algae, soil — to produce disinfection byproducts (DBPs). Over 600 DBPs have been identified. The EPA regulates two groups: total trihalomethanes (TTHMs, including chloroform) and haloacetic acids (HAA5). DBP levels tend to be highest in surface water systems and in warm months when organic matter is elevated.
EPA limit: 80 µg/L (TTHMs) / 60 µg/L (HAA5)
Arsenic
Arsenic (As) occurs naturally in rock and soil, dissolving into groundwater through natural weathering processes. Inorganic arsenic — the form found in drinking water — is a known human carcinogen. The western United States has particularly arsenic-rich geological formations, but elevated levels have been found in 48 states. Arsenic is tasteless and odorless.
EPA limit: 10 ppb
City Water Reports in Colorado
Tap water quality pages for Colorado cities — violations, PFAS records, utility profiles, and official source links.
Independent Water Testing
Find a certified lab in Colorado
Utility compliance records show what water systems report to the EPA. An independent test from a certified laboratory confirms what's actually in your tap water. Colorado labs can test for PFAS, lead, nitrates, bacteria, and dozens of other contaminants.
Explore Water Quality in Colorado
Green Mountain Wsd
Violation history, PFAS records, and official source links
City of Northglenn
Violation history, PFAS records, and official source links
Southwest Metropolitan Wsd
Violation history, PFAS records, and official source links
PFAS monitoring records — Colorado
154 water systems in Colorado with EPA UCMR 5 records
Lead in Colorado drinking water
State-specific lead data, violation utilities, and testing guidance
PFAS in Colorado drinking water
State-specific PFAS data, MCL context, and treatment options
Certified water testing labs in Colorado
Labs certified for PFAS (EPA 533/537.1), lead, and bacteria testing
Water treatment options
Reverse osmosis, activated carbon, and filtration guides with cost ranges
Data sources and methodology
How WaterUtilityReport.com sources and validates official EPA data
Common Questions About Colorado Drinking Water
Does Colorado drinking water have PFAS?
154 Colorado water systems have EPA UCMR 5 PFAS monitoring records (2023–2025)
Which Colorado water utilities have open violations?
Browse Colorado utility compliance records and violation history
How do I test my water in Colorado?
State-certified labs for PFAS (EPA 533/537.1), lead, nitrate, and bacteria testing
What treatment removes PFAS from CO tap water?
Reverse osmosis removes PFAS, lead, arsenic, and nitrates — cost, maintenance, and NSF certification explained
What do Colorado PFAS records tell me about my water?
EPA limits, health context, and what UCMR 5 detection above MRL means for your water
How is Colorado water quality data sourced here?
EPA SDWIS violations, UCMR 5 PFAS records, and CCR data — sources, accuracy notes, and limitations
Colorado Water FAQs
Data sources: Utility compliance and violation data from EPA SDWIS (Safe Drinking Water Information System). PFAS monitoring records from EPA UCMR 5 (Unregulated Contaminant Monitoring Rule 5, 2023–2025). Contaminant data from EPA and ATSDR public references. This page summarizes public records — it is not a compliance determination. Methodology →
Last updated: 2026-04-18