Skip to main content
WaterSafeCheck

Colorado Tap Water Quality Report

Water quality grades, lead levels, and violation data for all 658 ZIP codes in Colorado

ZIP Codes

658

Health Violations (5yr)

671

Avg Safety Score

59.9/100

High Lead Risk ZIPs

38.8%

Overview: Drinking Water in Colorado

Drinking water quality in Colorado faces notable challenges, currently scoring below the national average with a composite safety score of 59.9/100 across 658 monitored ZIP codes. According to the EPA's Safe Drinking Water Information System, 1% of ZIP codes in the state have received a failing grade. These scores reflect historical struggles with aging infrastructure, localized contamination events, and recurring health-based violations that require active intervention by local utilities.

The state's water infrastructure has experienced significant compliance hurdles recently, logging a staggering 671 health-based violations over the past 5-year monitoring window out of 4,570 total violations. When a state registers this volume of health-based violations, it often points to systemic challenges such as aging distribution networks, agricultural runoff affecting groundwater, or underfunded rural water systems. Colorado Department of Public Health and Environment is responsible for enforcing corrective actions and penalizing systems that repeatedly fail to meet safe drinking water standards.

One of the most pressing concerns for Colorado residents is the elevated risk of lead exposure. EPA models and historical monitoring indicate that 38.8% of ZIP codes in Colorado are classified as High or Very High risk for lead. This is frequently associated with older housing stock built before the 1986 federal ban on lead pipes and solder. Residents living in older homes should strongly consider having their tap water independently tested and utilizing a certified NSF/ANSI 53 water filter for drinking and cooking.

Surface Water

74.8%

of ZIP codes

Total Violations

4,570

5-year record

Grade A ZIPs

0

0% of state

Grade F ZIPs

9

1% of state

Water Quality Grade Distribution in Colorado

How do Colorado's 658 ZIP codes stack up by water quality grade?

A
0 ZIP codes0%
B
57 ZIP codes9%
C
426 ZIP codes65%
D
166 ZIP codes25%
F
9 ZIP codes1%

Water Quality by City in Colorado

Click any city to view ZIP code-level water quality reports

Denver

69 ZIPs

C

Colorado Springs

55 ZIPs

C

Aurora

17 ZIPs

D

Littleton

16 ZIPs

C

Boulder

16 ZIPs

C

Pueblo

12 ZIPs

C

Fort Collins

9 ZIPs

C

Arvada

7 ZIPs

C

Englewood

7 ZIPs

C

Grand Junction

7 ZIPs

C

Greeley

6 ZIPs

C

Broomfield

4 ZIPs

C

Westminster

4 ZIPs

C

Golden

4 ZIPs

C

Longmont

4 ZIPs

C

Castle Rock

3 ZIPs

C

Steamboat Springs

3 ZIPs

C

Loveland

3 ZIPs

D

Brighton

3 ZIPs

C

Gunnison

3 ZIPs

C

Durango

3 ZIPs

C

Montrose

3 ZIPs

C

Commerce City

2 ZIPs

C

Louisville

2 ZIPs

C

Wheat Ridge

2 ZIPs

D

Parker

2 ZIPs

C

Evergreen

2 ZIPs

D

Silverthorne

2 ZIPs

C

Estes Park

2 ZIPs

C

Windsor

2 ZIPs

C

Limon

2 ZIPs

C

U S A F Academy

2 ZIPs

D

Woodland Park

2 ZIPs

C

Crowley

2 ZIPs

D

Alamosa

2 ZIPs

B

Pagosa Springs

2 ZIPs

B

Canon City

2 ZIPs

C

Crested Butte

2 ZIPs

C

Florence

2 ZIPs

C

Glenwood Springs

2 ZIPs

C

🏆 Highest Rated ZIP Codes in Colorado

81123Blanca
83/100
B
81128Chromo
83/100
B
81151Sanford
83/100
B
81655Wolcott
83/100
B
81658Vail
83/100
B

⚠ Lowest Rated ZIP Codes in Colorado

80746Paoli
31/100
F
81030Cheraw
33/100
F
81047Holly
33/100
F
81058Manzanola
33/100
F
80536Livermore
34/100
F

Common Drinking Water Contaminants in Colorado

The following are common regulated contaminants found in Colorado drinking water based on EPA violation records. Click any contaminant to learn about EPA safety limits and health effects.

Chlorine residualE. coliContaminant 0700Stage 1 DBP RuleFecal ColiformStage 2 DBP RuleGross BetaHaloacetic Acids (HAA5)

Source: EPA Safe Drinking Water Act Maximum Contaminant Level regulations. For the complete list of regulated contaminants and MCLs, see the Water Quality Safety Guide.

Frequently Asked Questions — Colorado Drinking Water

Is tap water generally safe to drink in Colorado?+
Yes, for the majority of residents, tap water in Colorado is treated, heavily regulated, and safe to drink. However, safety varies significantly by location. Statewide, 0 ZIP codes earn an "A" grade for perfect compliance, while 9 earn an "F" due to historical violations. It is essential to search your specific ZIP code above to view the exact compliance record for your local water utility.
What are the biggest water quality issues in Colorado?+
Based on a 5-year analysis of EPA violation data, the primary water quality challenges in Colorado include managing 671 health-based violations statewide and addressing infrastructure age. Additionally, 38.8% of ZIP codes in the state are rated as having a High or Very High probability of lead exposure risk, which is a key metric residents should monitor.
Who regulates and enforces drinking water standards in Colorado?+
Drinking water in Colorado is primarily regulated by Colorado Department of Public Health and Environment under a primacy agreement with the U.S. Environmental Protection Agency (EPA). The EPA sets the federal baseline standards (Maximum Contaminant Levels) through the Safe Drinking Water Act, while Colorado Department of Public Health and Environment conducts the day-to-day monitoring, issues compliance orders, and enforces penalties against local water systems that fail to meet these standards.
Where does Colorado get its drinking water?+
Water sources in Colorado vary widely by municipality. Statewide, approximately 74.8% of the monitored ZIP codes rely on surface water sources (such as rivers, lakes, and reservoirs), which require extensive filtration and disinfection. The remaining systems primarily rely on groundwater pumped from underground aquifers, which is naturally filtered but can be susceptible to agricultural runoff or naturally occurring minerals.
How do I find the official water quality report for my home in Colorado?+
You can enter your ZIP code in our search box above for a detailed, easy-to-read report based on EPA data. Furthermore, your local water utility is required by federal law to distribute an annual Consumer Confidence Report (CCR) by July 1 of each year. You can contact your utility directly to request this document, which outlines exact contaminant measurements from the previous year.
View All 658 ZIP Codes in Colorado

Browse EPA water quality data for every monitored ZIP code. For faster results, use the search bar above.

800018000280003800048000580006800078001080011800128001380014800158001680017800188001980020800218002280023800248002580026800278002880030800318003380034800358003680037800388004080041800428004480045800468004780101801028010380104801058010680107801088010980110801118011280113801168011780118801208012180122801238012480125801268012780128801298013080131801328013380134801358013680137801388015080151801558016080161801628016380165801668020180202802038020480205802068020780208802098021080211802128021480215802168021780218802198022080221802228022380224802258022680227802288022980230802318023280233802348023580236802378023880239802418024380244802468024780248802498025080251802528025680257802598026080261802628026380264802658026680271802738027480279802808028180290802918029380294802958029980301803028030380304803058030680307803088030980310803148032180322803238032880329804018040280403804198042080421804228042380424804258042680427804288042980430804328043380434804358043680437804388043980440804428044380444804468044780448804498045180452804538045480455804568045780459804618046380465804668046780468804698047080471804738047480475804768047780478804798048080481804828048380487804888049780498805018050280503805048051080511805128051380514805158051680517805208052180522805238052480525805268052780528805308053280533805348053580536805378053880539805408054180542805438054480545805468054780549805508055180553806018060280603806108061180612806148061580620806218062280623806248063180632806338063480638806398064080642806438064480645
+ 358 more ZIP codes — please search by city above