Is Marbleton, WY Tap Water Safe to Drink?
Graded D+, with 9 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
52/100
waterverge.com Marbleton, WY — Water Quality Report
Marbleton's drinking water received a grade of D+ (52 out of 100), indicating poor water quality. The city's 1 water system serves approximately 861 residents using groundwater.
Lead levels were measured at 0.0 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 912 violations on record, including 4 health-based violations. 9 remain unresolved.
What to know about Marbleton's water
Marbleton ranks #47 out of 65 cities in Wyoming for water quality, placing it below average in the state.
Marbleton 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.
As a small community water system, Marbleton may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Marbleton, WY water safe to drink?
Marbleton's drinking water has significant quality concerns based on EPA testing data. With a grade of D+ (52/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 861 residents using groundwater (wells).
Recent water quality updates for Marbleton
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Marbleton's water quality assessment. Grade: D+ (52/100).
Contaminants: Nitrate-Nitrite.
1 health-based. Contaminants: Groundwater Rule.
Contaminants: Nitrate-Nitrite.
Key contaminant findings
Based on the most recent EPA sampling data for Marbleton's water supply.
Well within EPA limits.
Violation history
Marbleton's water system has 912 total violations on record, including 4 health-based violations. 9 remain unresolved. 4 violations were issued in the last 5 years.
Where does Marbleton's water come from?
Marbleton's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 861 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.
What Marbleton residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Marbleton'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.
Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.
Top contaminants to know
View all ↓Violation summary
Violations & advisories
Drought conditions
D2 — severe droughtSublette County is currently in D2 (severe drought) per the U.S. Drought Monitor (week of May 5, 2026). 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.
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. | 0.0 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Marbleton compares by contaminant
Explore where Marbleton ranks among all Wyoming cities for specific contaminants.
Water source & infrastructure
Where Marbleton's water comes from
Marbleton's drinking water is drawn from underground aquifers through wells.
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 861 people through 1 water system.
Water systems serving Marbleton
| System Name | PWSID | Population | Source |
|---|---|---|---|
| MARBLETON, TOWN OF | WY5600223 | 861 | GW |
How Marbleton compares
Full Wyoming rankings →Marbleton's score of 52/100 is on par with the average of 55/100 among major Wyoming cities. It outscores 5 of 10 nearby cities.
Nearby cities
View Wyoming rankings →About Marbleton, WY
Wikipedia →Marbleton is a town in Sublette County, Wyoming, United States. As of the 2020 census, Marbleton had a population of 861.
Learn more about your water
Guides and resources related to Marbleton's water quality findings.
Explore water quality across Sublette
Frequently asked questions
Is Marbleton, WY tap water safe to drink?
Marbleton's water quality earned a grade of D+ (52/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #47 out of 65 cities tested in Wyoming.
What contaminants are in Marbleton's water?
Lead was measured at 0.0 ppb (90th percentile). 912 violations are on record.
How is Marbleton'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 Marbleton?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Marbleton's water come from?
Marbleton's water is sourced from Groundwater. The city has 1 water system serving approximately 861 residents.
What health violations has Marbleton's water system had?
Marbleton has 4 health-based violations on record. The most recent violation was recorded in January 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 9 violations remain unresolved.
Is Marbleton's groundwater at risk of contamination?
Marbleton 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 912 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 Marbleton's water compare to other cities?
Marbleton ranks #47 out of 65 cities in Wyoming (better than 28% of state cities) and #12831 out of 15744 cities nationally (19th percentile). The grade of D+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Marbleton's small water system affect quality?
Marbleton's system serves approximately 861 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 912 violations on record.