Water Quality in Cheyenne, WY: 48 Violations — Grade F
Grade F · Score 35/100 · 5 water systems · Updated 2026-05-03
Cheyenne's water has serious compliance issues. Independent testing and filtration are strongly recommended.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
The compliance history for Cheyenne, WY includes 48 water violations on file with the EPA — a federal tally that spans health-based exceedances, monitoring failures, and enforcement actions logged under the Safe Drinking Water Act.
Water Quality Map: Cheyenne, WY
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Water Quality by ZIP Code in Cheyenne
Water quality varies across Cheyenne's 8 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 82002 | F | 32 | 6 | 1 | View report → |
| 82006 | F | 32 | 6 | 1 | View report → |
| 82008 | F | 32 | 6 | 1 | View report → |
| 82010 | F | 32 | 6 | 1 | View report → |
| 82001 | F | 34 | 6 | 1 | View report → |
| 82009 | F | 34 | 6 | 1 | View report → |
| 82007 | F | 39 | 6 | 1 | View report → |
| 82003 | D | 44 | 6 | 1 | View report → |
Water Quality Overview
Cheyenne, Wyoming receives a water quality grade of F with an overall score of 35 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
The 5 water systems serving Cheyenne have accumulated 48 EPA violations, including 8 health-based violations. These violations are tracked across 8 ZIP codes serving approximately 81,406 people.
What Grade F Means
A grade of F indicates serious compliance issues. Cheyenne's water systems have substantial violations. Residents should strongly consider independent water testing and appropriate filtration.
Lead Levels
The average 90th percentile lead level across Cheyenne water systems is 0.0150 mg/L — within EPA limits. No ZIP codes exceed the EPA lead action level.
With 56% of homes built before 1986, Cheyenne has a higher-than-average risk of lead from older plumbing. Lead solder was banned in 1986, and homes built before this date may have lead in pipes, solder joints, or fixtures.
Radon Risk
Cheyenne is in EPA Radon Zone 1 (High risk). The EPA recommends all homes in Zone 1 areas be tested for radon. Radon is the second leading cause of lung cancer after smoking.
Water Systems Serving Cheyenne
Cheyenne is served by 5 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 81,406 people across 8 ZIP codes.
Each water system is identified by a Public Water System ID (PWSID) and is required to:
- Test for over 90 regulated contaminants on a regular schedule
- Report results to the EPA and state regulators
- Issue an annual Consumer Confidence Report (CCR) to all customers
- Take corrective action when violations occur
The EPA has taken 80 enforcement actions against water systems serving Cheyenne. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Cheyenne
Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels, violation history, and safety scores
Request your CCR — your water utility must provide an annual Consumer Confidence Report with detailed test results for all monitored contaminants
Get a home test — certified kits cost $20–$50 and test for lead, bacteria, and common contaminants. Professional lab tests ($150–$400) cover a broader panel
Consider filtration — NSF-certified filters can remove specific contaminants. Reverse osmosis removes the broadest range; activated carbon is effective for chlorine and many organics
Check for advisories — monitor your local utility website and local news for boil water advisories or system alerts
Contaminants Detected in Cheyenne Water Systems
The following contaminants have been detected or caused violations across Cheyenne's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 0.08 mg/L | 16 | 8 | No |
| Surface Water Treatment Rule | Treatment Technique | N/A | 8 | 8 | No |
| E. coli | Microbiological | N/A | 8 | 8 | No |
MCL = Maximum Contaminant Level (EPA enforceable standard). Health-based violations indicate levels that may pose direct health risks.
EPA Enforcement History
The EPA and state regulators have taken 10 enforcement actions against water systems serving Cheyenne. Recent actions:
| Date | Action Type |
|---|---|
| 2025-03-03 | State Order Extension |
| 2024-08-14 | State Informal Action |
| 2024-02-22 | State Order Extension |
| 2024-02-22 | State Informal Action |
| 2024-01-31 | State Informal Action |
| 2023-12-11 | State Order Extension |
| 2023-06-05 | State Order Extension |
| 2023-05-27 | State Order Extension |
| 2022-07-07 | State Informal Action |
| 2022-05-11 | State Order Extension |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2025-03-03.
Cheyenne vs. Nearby Wyoming Cities
How Cheyenne's water quality compares to similar cities in Wyoming:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Cheyenne | F | 48 | 5 | 81,406 |
| Casper | C | 35 | 5 | 65,203 |
| Fe Warren Afb | D | 0 | 1 | 64,165 |
| Granite Canon | D | 0 | 1 | 64,165 |
Water Quality by ZIP Code in Cheyenne
Water quality varies across Cheyenne's ZIP codes. The table below shows the worst-scoring and best-scoring areas:
| ZIP Code | Score | Grade | Violations | Health-Based |
|---|---|---|---|---|
| 82002 | 32 | F | 6 | 1 |
| 82006 | 32 | F | 6 | 1 |
| 82008 | 32 | F | 6 | 1 |
| 82010 | 32 | F | 6 | 1 |
| 82001 | 34 | F | 6 | 1 |
| 82009 | 34 | F | 6 | 1 |
| 82007 | 39 | F | 6 | 1 |
| 82003 | 44 | D | 6 | 1 |
Common Questions About Cheyenne Water
These are the most common questions residents search for about water quality in Cheyenne, Wyoming:
Is Cheyenne water hard or soft? Water hardness varies by source. Cheyenne's 5 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Cheyenne tap water? Cheyenne's water receives a grade of F (35/100). There are 8 health-based violations — consider filtration.
What is the best water filter for Cheyenne? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Cheyenne vs. Wyoming Average
Understanding how Cheyenne compares to the broader Wyoming average helps contextualize your local water quality. Factors like water source, treatment methods, and infrastructure age all contribute to differences between cities in the same state.
To see how individual neighborhoods compare, check the ZIP code reports below — water quality can vary significantly even within Cheyenne.
ZIP Codes in Cheyenne
Cheyenne spans 8 ZIP codes. The ZIP with the lowest water quality score is 82001. Each ZIP code has its own water quality profile based on the specific water system serving that area. Check each ZIP code for detailed contaminant data, violation history, and system information.
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
- Enforcement: EPA ECHO database
- Filter recommendations: NSF/ANSI certified products
Updated daily.