WaterVerge

Is Shoshoni, WY Tap Water Safe to Drink?

Graded A-, with 5 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

515 residents served 1 water system PWSID: WY5600053
Overall Score
88.1 / 100
Violations
5 active
Last Updated
May 2026
Source
Groundwater
#13 of 65 in Wyoming Top 23% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
A-GRADE
Water Quality Grade
88.1/100
waterverge.com
A- 88.1/100

Shoshoni, WY — Water Quality Report

Shoshoni's drinking water received a grade of A- (88.1 out of 100), indicating good water quality. The city's 1 water system serves approximately 515 residents using groundwater.

Lead levels were measured at 4.0 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 41 violations on record, including 3 health-based violations. 5 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Shoshoni's water

Shoshoni ranks #13 out of 65 cities in Wyoming for water quality, placing it above average in the state.

Shoshoni 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, Shoshoni may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.

Quality Breakdown

Water quality score

See methodology →
88.1 out of 100 Grade A-
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
40.6/45
A
Historical violation record including health-based and monitoring violations.
Lead & Copper
18/20
A
Lead at 4.0 ppb (90th percentile).
Contaminants
16.5/20
B
PFAS + legacy contaminant analysis.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Shoshoni, WY water safe to drink?

Concerns Identified

Shoshoni's drinking water has significant quality concerns based on EPA testing data. With a grade of A- (88.1/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 515 residents using groundwater (wells).

5
Active Violations
4.0 ppb
Lead (90th %ile)
2 events
Disaster History

Recent water quality updates for Shoshoni

A timeline of significant water quality events, violations, and data updates.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Shoshoni's water quality assessment. Grade: A- (88.1/100).

Violation
1 drinking water violation recorded

Contaminants: Chlorine.

Violation
1 drinking water violation recorded

Contaminants: Lead and Copper Rule.

Violation
1 drinking water violation recorded

Contaminants: Consumer Confidence Rule.

Disaster
FLOODING

Federal disaster declaration (FEMA DR-4327). Flood event — may have impacted local water infrastructure.

Disaster
FLOODING

Federal disaster declaration (FEMA DR-1923). Flood event — may have impacted local water infrastructure.

Key contaminant findings

Based on the most recent EPA sampling data for Shoshoni's water supply.

Lead Within Limits
Detected: 4.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Violation history

Shoshoni's water system has 41 total violations on record, including 3 health-based violations. 5 remain unresolved. 1 violation was issued in the last 5 years.

MROtherMONMCL
Most recent violations:
Aug 2025 Chlorine Resolved
Dec 2020 Lead and Copper Rule Open
Jul 2020 Consumer Confidence Rule Open
Jan 2020 Nitrate-Nitrite Resolved
Jan 2020 Nitrate-Nitrite Resolved

Flood & environmental risk

Fremont County has experienced 2 federally declared disasters since 2010. 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 Wind River Ab Boysen Reservoir, Nr Shoshoni, Fivemile Creek.

FLOODING
Flood FEMA DR-4327
FLOODING
Flood FEMA DR-1923

Where does Shoshoni's water come from?

Shoshoni's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 515 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Wind River Ab Boysen Reservoir, Nr Shoshoni (river), Fivemile Creek (river).

What Shoshoni residents can do

Install a water filter

Recommended: NSF-certified water filter. This addresses the specific contaminants found in Shoshoni's water.

Request your utility's CCR

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.

Flush your taps

Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
4.0 ppb
EPA Action Level: 15 ppb · 27% of limit
Safe Level
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
0.4 µg/L
EPA MCL: 60 µg/L · 1% of limit
Within LimitUCMR 4 DataHAA6Br: 0.6 µg/LHAA9: 0.6 µg/L
Manganese
Inorganic
Detected
2.3 µg/L
EPA Secondary MCL: 50 µg/L · 5% of limit
DetectedUCMR 4 Data
Compliance Record

Violation summary

41
Total violations
3
Health-based
5
Active / unresolved
Aug 2025
Most recent violation
Compliance Record

Violations & advisories

41 Total
5 Active
3 Health-based
36 Resolved
Violations by category
Synthetic Organic Chemicals
26
Total Coliform Rule
3
Lead and Copper Rule
2
Consumer Confidence Rule
2
Nitrate Rule
2
Dec 2020 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2020 Active
Consumer Confidence Rule
Other Violation 0
Oct 2015 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2015 Active
Consumer Confidence Rule
Other Violation 0
Active
Compliance Violation
Monitoring 0
Aug 2025 Resolved
Chlorine
Monitoring & Reporting
Monitoring & Reporting Resolved Aug 2025
Jan 2020 Resolved
Nitrate-Nitrite
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2020
Jan 2020 Resolved
Nitrate-Nitrite
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2020
Aug 2017 Resolved
Revised Total Coliform Rule
Monitoring
Monitoring Resolved Aug 2017
Jan 2008 Resolved
Benzo(a)pyrene
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2008 Resolved
Pentachlorophenol
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2008 Resolved
Total Polychlorinated Biphenyls (PCB)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2008 Resolved
Chlordane
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2008 Resolved
Methoxychlor
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2008 Resolved
Toxaphene
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2008 Resolved
Dalapon
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2008 Resolved
Picloram
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2008 Resolved
Atrazine
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2008 Resolved
Heptachlor epoxide
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2008 Resolved
Endrin
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Showing 20 of 41 violations
Environmental Risk

Drought conditions

D2 — severe drought

Fremont 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.

12
Weeks at D2+ (current streak)
40.1%
Months in D2+ (last 30y)
12
Weeks at D2+ (last 5y)

Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.

Environmental Risk

Flood & disaster history

2
Declared disasters
Aug 2017
Most recent
Flood
Most common type

Fremont County has experienced 2 federally declared disasters since 2010. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Aug 2017
FLOODING
Flood FEMA #4327
Jul 2010
FLOODING
Flood FEMA #1923

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 4.0 15 ppb Inorganic Safe
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has increased by 2.0 ppb from 2005 (2.0 ppb) to 2024 (4.0 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
515
Water Systems
1
Water Source

Where Shoshoni's water comes from

Groundwater

Shoshoni'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 515 people through 1 water system.

Local Hydrology

Water bodies near Shoshoni

Shoshoni is located near 2 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

Wind River Ab Boysen Reservoir, Nr Shoshoni
river
Fivemile Creek
river
Infrastructure

Water systems serving Shoshoni

System Name PWSID Population Source
SHOSHONI, TOWN OF WY5600053 515 GW
Regional Comparison

How Shoshoni compares

Full Wyoming rankings →

Shoshoni's score of 88.1/100 is above the average of 55/100 among major Wyoming cities. It outscores 10 of 10 nearby cities.

Shoshoni (this city)
88.1
Cheyenne
30.8
Casper
41.8
Gillette
44.5
Laramie
55.2
Jackson
43.2
Wyoming avg
55
City Profile

About Shoshoni, WY

Wikipedia →

Shoshoni is a town in Fremont County, Wyoming, United States. The population was 471 at the 2020 census, a 27.4% decline from 649 at the 2010 census.

Economic Profile
$39,485
Median Income
$738/mo
Median Rent
5.8%
Unemployment
Community
40.4
Median Age
69
People / sq mi
6.4%
College Educated
75.5%
Homeownership
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Frequently asked questions

Is Shoshoni, WY tap water safe to drink?

Shoshoni's water quality earned a grade of A- (88.1/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #13 out of 65 cities tested in Wyoming.

What contaminants are in Shoshoni's water?

Lead was measured at 4.0 ppb (90th percentile). 41 violations are on record.

How is Shoshoni'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 Shoshoni?

Based on current data, basic filtration should suffice for additional peace of mind.

Where does Shoshoni's water come from?

Shoshoni's water is sourced from Groundwater. The city has 1 water system serving approximately 515 residents.

What health violations has Shoshoni's water system had?

Shoshoni has 3 health-based violations on record. The most recent violation was recorded in August 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 5 violations remain unresolved.

Is Shoshoni's groundwater at risk of contamination?

Shoshoni 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 41 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 Shoshoni's water compare to other cities?

Shoshoni ranks #13 out of 65 cities in Wyoming (better than 80% of state cities) and #3667 out of 15744 cities nationally (77th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

Does Shoshoni's small water system affect quality?

Shoshoni's system serves approximately 515 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 41 violations on record.