WaterVerge

Is Gillette, WY Tap Water Safe to Drink?

Graded F — but Strontium was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

45K residents served 43 water systems PWSID: WY5600019
Overall Score
44.5 / 100
Violations
75 active
Last Updated
May 2026
Source
Groundwater
#57 of 65 in Wyoming Top 91% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
FGRADE
Water Quality Grade
44.5/100
waterverge.com
F 44.5/100

Gillette, WY — Water Quality Report

Gillette's drinking water received a grade of F (44.5 out of 100), indicating failing water quality. The city's 43 water systems serve approximately 45,252 residents using groundwater.

Lead levels were measured at 4.0 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 1 PFAS compound in the water supply.

The system has 1227 violations on record, including 89 health-based violations. 75 remain unresolved.

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

What to know about Gillette's water

Gillette ranks #57 out of 65 cities in Wyoming for water quality, placing it among the lowest-rated in the state.

Gillette 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.

PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter.

Hexavalent chromium (chromium-6) was detected at 0.19 µg/L in UCMR 3 testing. While below California's 10 µg/L limit and with no federal MCL set, residents sensitive to this contaminant may consider reverse osmosis filtration.

The system has seen 251 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
44.5 out of 100 Grade F
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
0/45
F
Historical violation record including health-based and monitoring violations.
Lead & Copper
18/20
A
Lead at 4.0 ppb (90th percentile).
Contaminants
13.5/20
C
1 PFAS compound detected.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Gillette, WY water safe to drink?

Concerns Identified

Gillette's drinking water has significant quality concerns based on EPA testing data. With a grade of F (44.5/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 43 water systems serve approximately 45,252 residents using groundwater (wells).

75
Active Violations
4.0 ppb
Lead (90th %ile)
1 compound
PFAS Detected
1 event
Disaster History

Recent water quality updates for Gillette

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

PFAS
1 PFAS "forever chemical" compound detected

Detected at levels within current EPA limits. PFAS persist indefinitely in the environment.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Gillette's water quality assessment. Grade: F (44.5/100).

Violation
2 drinking water violations recorded

Contaminants: Revised Total Coliform Rule, Chlorine.

Violation
2 drinking water violations recorded

Contaminants: E. COLI, Chlorine.

Violation
2 drinking water violations recorded

Contaminants: E. COLI, Chlorine.

Disaster
SEVERE STORMS, FLOODING & MUDSLIDES

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 Gillette's water supply.

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

Well within EPA limits.

PFAS (1 compound) Elevated
Detected: Highest: lithium at 14.3000 µg/L Limit: 0.004 µg/L (EPA MCL)

Detected but within current EPA limits. PFAS do not break down in the environment and can accumulate in the body over time. An activated carbon filter can reduce exposure.

Violation history

Gillette's water system has 1,227 total violations on record, including 89 health-based violations. 75 remain unresolved. 251 violations were issued in the last 5 years.

MONMRRPTTTOtherMCL
Most recent violations:
Dec 2025 Revised Total Coliform Rule Resolved
Dec 2025 Chlorine Resolved
Sep 2025 E. COLI Open
Sep 2025 Chlorine Resolved
Aug 2025 E. COLI Open

Flood & environmental risk

Campbell 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.

SEVERE STORMS, FLOODING & MUDSLIDES
Flood FEMA DR-557

Where does Gillette's water come from?

Gillette's drinking water comes from groundwater (wells), supplied by 43 water systems serving approximately 45,252 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.

What Gillette residents can do

Install a water filter

Recommended: Activated carbon or reverse osmosis filter. This addresses the specific contaminants found in Gillette'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
lithium
PFAS / Forever Chemical
Near MCL
14.3000 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
1.6 µg/L
EPA MCL: 60 µg/L · 3% of limit
Within LimitUCMR 4 DataHAA6Br: 2.4 µg/LHAA9: 3.6 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
0.19 µg/L
CA MCL (no federal MCL): 10 µg/L · 2% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Over HRL
2000.0 µg/L
EPA Health Ref Level: 1,500 µg/L · +20% over limit
Over HRLUCMR 3 Data
Manganese
Inorganic
Detected
24.1 µg/L
EPA Secondary MCL: 50 µg/L · 48% of limit
DetectedUCMR 4 Data
Vanadium
Inorganic
Detected
3.10 µg/L
EPA Short-term HA: 21 µg/L · 15% of limit
DetectedUCMR 3 Data
Molybdenum
Inorganic
Elevated
21.00 µg/L
EPA Lifetime HA: 40 µg/L · 53% of limit
DetectedUCMR 3 Data
Lithium
Inorganic
Detected
14.3 µg/L
State screening level: 60 µg/L · 24% of limit
DetectedNo federal MCLUCMR 5 Data (2023–2025)
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
1
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

1227
Total violations
89
Health-based
75
Active / unresolved
Dec 2025
Most recent violation
Compliance Record

Violations & advisories

1227 Total
75 Active
89 Health-based
1152 Resolved
2 SNC
Violations by category
Volatile Organic Chemicals
387
Total Coliform Rule
297
Radionuclides and Revised Rad Rule
145
Synthetic Organic Chemicals
143
Inorganic Chemicals
97
Sep 2025 Active
E. COLI
Monitoring & Reporting
Monitoring & Reporting 0
Aug 2025 Active
E. COLI
Monitoring & Reporting
Monitoring & Reporting 0
Dec 2024 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Reporting
Reporting 0
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Treatment Technique
Health-Based Health 0
Aug 2024 Active
Revised Total Coliform Rule
Other Violation 0
Jul 2024 Active
Consumer Confidence Rule
Other Violation 0
Nov 2023 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Jul 2023 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Dec 2021 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Dec 2020 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Dec 2020 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Dec 2020 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Dec 2020 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2020 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2018 Active
Consumer Confidence Rule
Other Violation 0
Oct 2017 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Sep 2017 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Mar 2017 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Dec 2016 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Showing 20 of 1227 violations
Industrial pollution

Top industrial polluters within 10 miles of Gillette

Industrial polluters nearby

Reported releases to surface water by facilities near Gillette, ranked by pounds discharged annually.

Total reported releases to surface water: 38 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
BLACK HILLS CORP - NEIL SIMPSON COMPLEX
Electric Utilities · BLACK HILLS CORP
GILLETTE, WY82718
Barium And Barium Compounds385.3 mi
JOY GLOBAL GILLETTE WY
Machinery · KOMATSU MINING CORP
GILLETTE, WY82718
2.2 mi
BUCKSKIN MINING CO GILLETTE WY
Coal Mining · KIEWIT MINING GROUP
GILLETTE, WY82716
8.1 mi
PACIFICORP WYODAK PLANT
Electric Utilities · BERKSHIRE HATHAWAY INC
GILLETTE, WY82718
6.0 mi
BASIN ELECTRIC DRY FORK STATION
Electric Utilities · BASIN ELECTRIC POWER COOPERATIVE
GILLETTE, WY82716
9.3 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Environmental Risk

Drought conditions

D3 — extreme drought

Campbell County is currently in D3 (extreme 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)
24.0%
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

1
Declared disasters
May 1978
Most recent
Flood
Most common type

Campbell 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.

May 1978
SEVERE STORMS, FLOODING & MUDSLIDES
Flood FEMA #557

Recommended water filters

Based on contaminants detected in Gillette's water supply, we recommend the following filter types.

🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
1 PFAS compound detected

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 4.0 15 ppb Inorganic Safe
11Cl-PF3OUdS ND HI µg/L PFAS Not Detected
4:2 FTS ND HI µg/L PFAS Not Detected
6:2 FTS ND HI µg/L PFAS Not Detected
8:2 FTS ND HI µg/L PFAS Not Detected
9Cl-PF3ONS ND HI µg/L PFAS Not Detected
ADONA ND HI µg/L PFAS Not Detected
HFPO-DA ND 0.01 µg/L PFAS Not Detected
lithium 14.300 HI µg/L PFAS Detected
NEtFOSAA ND HI µg/L PFAS Not Detected
NFDHA ND HI µg/L PFAS Not Detected
NMeFOSAA ND HI µg/L PFAS Not Detected
PFBA ND HI µg/L PFAS Not Detected
PFBS ND HI µg/L PFAS Not Detected
PFDA ND HI µg/L PFAS Not Detected
PFDoA ND HI µg/L PFAS Not Detected
PFEESA ND HI µg/L PFAS Not Detected
PFHpA ND HI µg/L PFAS Not Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA ND HI µg/L PFAS Not Detected
PFHxS ND HI µg/L PFAS Not Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA ND HI µg/L PFAS Not Detected
PFOA ND 0.004 µg/L PFAS Not Detected
PFOS ND 0.004 µg/L PFAS Not Detected
PFPeA ND HI µg/L PFAS Not Detected
PFPeS ND HI µg/L PFAS Not Detected
PFTA ND HI µg/L PFAS Not Detected
PFTrDA ND HI µg/L PFAS Not Detected
PFUnA ND HI µg/L PFAS Not Detected
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has increased by 1.0 ppb from 2001 (0.0 ppb) to 2025 (1.0 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
45,252
Water Systems
43
Source breakdown
Groundwater
34
Purchased Groundwater
9
Water Source

Where Gillette's water comes from

Groundwater

Gillette'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 45,252 people through 43 water systems.

Infrastructure

Water systems serving Gillette

System Name PWSID Population Source
GILLETTE, CITY OF WY5600019 32,222 GW
SLEEPY HOLLOW SUBDIVISION WY5600764 2,400 GW
ANTELOPE VALLEY I&S DISTRICT (AVISD) WY5600251 1,280 GW
FOX PARK SUBDIVISION WY5600745 843 GW
HERITAGE VILLAGE SUBDIVISION WY5600249 750 GW
FOOTHILLS MOBILE HOME PARK WY5601239 735 GWP
EASTVIEW MANUFACTURED HOME COMMUNITY WY5601353 688 GWP
CRESTVIEW ESTATES SUBDIVISION WY5600853 500 GW
WESTVIEW MHC WY5601593 416 GWP
MEANS IMPROVEMENT & SERVICE DISTRICT WY5600760 410 GW
NICKELSON FARMS WATER COMPANY WY5600619 400 GW
FREEDOM HILLS SUBDIVISION WY5600789 400 GW
COUNTRYSIDE WATER USERS, INC. WY5600192 360 GW
HIGHVIEW MFG MOBILE HOME COMMUNITY (MHC) WY5600120 304 GWP
COOK ROAD WATER DISTRICT WY5601399 291 GW
CEDAR HILLS WATER ASSOCIATION WY5600780 258 GW
WRANGLER ESTATES WY5601474 250 GW
AMERICAN ROAD W&S DISTRICT WY5600968 220 GW
STONE GATE ESTATES WY5601329 198 GW
FORCE ROAD JOINT POWERS BOARD WY5600148 195 GW
PEOPLE`S IMPROVEMENT & SERVICE DISTRICT WY5600898 176 GW
LEX MOBILE HOME PARK WY5601742 172 GWP
SOUTHFORK ESTATES WY5600832 144 GW
BENNOR ESTATES & IMPROVEMENT DISTRICT WY5601596 144 GWP
EAGLE RIDGE MHP, LLC WY5600119 140 GW
GREEN VALLEY ESTATES I&S DISTRICT WY5601245 140 GW
NORTH GURLEY MOBILE HOME PARK WY5601721 128 GWP
EIGHT MILE SUBDIVISION WY5600829 120 GW
SECTION 4 WATER SYSTEM INCORPORATED WY5601519 120 GW
HOY MOBILE HOME PARK WY5600141 100 GW
PLAY PARK LLC WY5600127 96 GW
ROZET RANCHETTES I&S DISTRICT WY5601620 85 GW
PINEVIEW I&S DISTRICT WY5601490 75 GW
STROUP TRAILER COURT WY5600145 74 GW
RODEO FLATS WY5601626 72 GW
OVERBROOK SUBDIVISION WY5601572 66 GW
RED HILLS SUBDIVISON WY5601657 62 GWP
MEADOW SPRINGS IMP & SERV WY5601507 45 GW
RAFTER D IMPROVEMENT & SERVICE DISTRICT WY5601609 40 GW
FOX RIDGE WATER SYSTEM WY5601615 38 GW
LAKEVIEW MOBILE HOME PARK WY5601449 36 GW
SOUTHSIDE WELL I&S DISTRICT WY5600122 30 GWP
HAGENS ESTATES WY5601739 29 GW
Regional Comparison

How Gillette compares

Full Wyoming rankings →

Gillette's score of 44.5/100 is below the average of 55/100 among major Wyoming cities. It outscores 5 of 10 nearby cities.

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

About Gillette, WY

Wikipedia →

Gillette is a city in and the county seat of Campbell County, Wyoming, United States. The town was founded in 1891 as a major railway town on the Chicago, Burlington and Quincy Railroad.

Economic Profile
$90,415
Median Income
$242,115
Median Home Value
$900/mo
Median Rent
3.6%
Unemployment
Community
33.2
Median Age
552
People / sq mi
22.6%
College Educated
75%
Homeownership
Share this reportHelp others learn about their water quality
WhatsAppXFacebookLinkedInEmail

Frequently asked questions

Is Gillette, WY tap water safe to drink?

Gillette's water quality earned a grade of F (44.5/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #57 out of 65 cities tested in Wyoming.

What contaminants are in Gillette's water?

Lead was measured at 4.0 ppb (90th percentile). 1 PFAS compound was detected. 1227 violations are on record.

How is Gillette'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 Gillette?

PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.

Where does Gillette's water come from?

Gillette's water is sourced from Groundwater. The city has 43 water systems serving approximately 45,252 residents.

What health violations has Gillette's water system had?

Gillette has 89 health-based violations on record. The most recent violation was recorded in December 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 75 violations remain unresolved.

Is Gillette's groundwater at risk of contamination?

Gillette 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 1227 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 Gillette's water compare to other cities?

Gillette ranks #57 out of 65 cities in Wyoming (better than 12% of state cities) and #14349 out of 15744 cities nationally (9th percentile). The grade of F reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.