Is Basin, WY Tap Water Safe to Drink?
Graded B+, with 11 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
84.3/100
waterverge.com Basin, WY — Water Quality Report
Basin's drinking water received a grade of B+ (84.3 out of 100), indicating good water quality. The city's 2 water systems serve approximately 2,150 residents using purchased ground water.
Lead levels were measured at 1.0 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 20 violations on record, including 3 health-based violations. 11 remain unresolved.
What to know about Basin's water
Basin ranks #20 out of 65 cities in Wyoming for water quality, placing it mid-range in the state.
Basin purchases its water from a regional wholesaler, meaning quality depends on both the supplier's treatment and the local distribution system's condition.
As a small community water system, Basin may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Basin, WY water safe to drink?
Basin's drinking water has significant quality concerns based on EPA testing data. With a grade of B+ (84.3/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 2,150 residents using groundwater (wells).
Recent water quality updates for Basin
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Basin's water quality assessment. Grade: B+ (84.3/100).
Contaminants: Chlorine.
Contaminants: Lead and Copper Rule.
Contaminants: Lead and Copper Rule.
Federal disaster declaration (FEMA DR-557). Flood event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Basin's water supply.
Well within EPA limits.
Violation history
Basin's water system has 20 total violations on record, including 3 health-based violations. 11 remain unresolved. 3 violations were issued in the last 5 years.
Flood & environmental risk
Big Horn County has experienced 1 federally declared disaster since 1978. 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 Bighorn River.
Where does Basin's water come from?
Basin's drinking water comes from groundwater (wells), supplied by 2 water systems serving approximately 2,150 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Bighorn River (river).
What Basin residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Basin'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 droughtBig Horn 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.
Flood & disaster history
Big Horn County has experienced 1 federally declared disaster since 1978. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
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. | 1.0 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Basin compares by contaminant
Explore where Basin ranks among all Wyoming cities for specific contaminants.
Water source & infrastructure
Where Basin's water comes from
Basin purchases its water supply from a regional wholesale provider rather than treating raw water directly.
Water quality depends on both the wholesaler's treatment standards and the condition of Basin's local distribution pipes and storage facilities.
Purchased water systems are common in suburban areas and smaller communities that lack the infrastructure for independent treatment.
The system is operated by local government ownership and serves approximately 2,150 people through 2 water systems.
Water bodies near Basin
Basin is located near 1 notable water body. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Basin
| System Name | PWSID | Population | Source |
|---|---|---|---|
| BASIN, TOWN OF | WY5600004 | 1,250 | GWP |
| SOUTH BIG HORN COUNTY JPB | WY5601454 | 900 | GW |
How Basin compares
Full Wyoming rankings →Basin's score of 84.3/100 is above the average of 55/100 among major Wyoming cities. It outscores 10 of 10 nearby cities.
Nearby cities
View Wyoming rankings →About Basin, WY
Learn more about your water
Guides and resources related to Basin's water quality findings.
Explore water quality across Big Horn
Frequently asked questions
Is Basin, WY tap water safe to drink?
Basin's water quality earned a grade of B+ (84.3/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #20 out of 65 cities tested in Wyoming.
What contaminants are in Basin's water?
Lead was measured at 1.0 ppb (90th percentile). 20 violations are on record.
How is Basin'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 Basin?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Basin's water come from?
Basin's water is sourced from Purchased ground water. The city has 2 water systems serving approximately 2,150 residents.
What health violations has Basin's water system had?
Basin has 3 health-based violations on record. The most recent violation was recorded in June 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 11 violations remain unresolved.
Is Basin's groundwater at risk of contamination?
Basin 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 20 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 Basin's water compare to other cities?
Basin ranks #20 out of 65 cities in Wyoming (better than 69% of state cities) and #5980 out of 15744 cities nationally (62th percentile). The grade of B+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.