Wyoming
Wyoming sits in the West and draws its water primarily from Colorado & Missouri headwaters and snowpack. With roughly 0.58 million residents, the state has minimal formal water reuse to date, reusing an estimated 3% of its treated wastewater.
Wyomingwater quality & safety
Top violation drivers in Wyoming
| Contaminant / rule | Systems |
|---|---|
| Groundwater Rule | 61 |
| Lead and Copper Rule | 13 |
| Long Term 2 Enhanced Surface Water Treatment Rule | 11 |
| Revised Total Coliform Rule | 9 |
| TTHM | 8 |
| LEAD AND COPPER RULE REVISIONS | 7 |
Source: EPA Safe Drinking Water Information System (SDWIS) · 2026 Q1 · health-based violations since 2016
A headwaters state with Colorado River obligations and irrigation-dominated use.
On the U.S. Drought Monitor scale, Wyoming currently tracks around severe to extreme conditions. Wyoming has 317 community water systems serving about 1 million people; EPA records show 110 of them (34.7%) with a health-based Safe Drinking Water Act violation since 2016. The pages below break down the water issues that matter most here and the communities working on solutions.
Drought history — severe+ extent
% of Wyoming in severe drought or worse (D2+) each late summer.
Source: U.S. Drought Monitor (NDMC/UNL, USDA, NOAA) · latest 2026-06-09
Water use (USGS 2015)
- Per-capita (public supply)
- 217 gpcd
- Total withdrawals
- 8.1 Bgal/d
- From groundwater
- 8.1%
- Irrigation share
- 95.6%
- Wastewater reused (est.)
- ~3%
Primary water sources
- ≈ Colorado & Missouri headwaters
- ≈ snowpack
Common questions
Is tap water safe in Wyoming?
Wyoming has 317 community water systems serving about 1 million people. EPA records show 110 of them (34.7%) with at least one health-based Safe Drinking Water Act violation since 2016, and 2 system(s) over the federal lead action level. Most large systems meet standards; check your specific city and your utility's annual report.
What contaminants are most common in Wyoming's water?
The most frequent health-based violations involve Groundwater Rule, Lead and Copper Rule, Long Term 2 Enhanced Surface Water Treatment Rule.
How much water does Wyoming use per person?
Public water systems in Wyoming withdraw about 217 gallons per person per day (USGS 2015), drawing 8.1% of fresh water from groundwater.
How bad is the drought in Wyoming?
As of 2026-06-09, 98.4% of Wyoming is in drought (D1+) and 83.4% is in severe drought or worse, per the U.S. Drought Monitor.
Cities in Wyoming
6 trackedCheyenne
Cheyenne, WY water profile — supply sources, drought status, wastewater reuse, and the key water issues facing the city.
Casper
Casper, WY water profile — supply sources, drought status, wastewater reuse, and the key water issues facing the city.
Gillette
Gillette, WY water profile — supply sources, drought status, wastewater reuse, and the key water issues facing the city.
Laramie
Laramie, WY water profile — supply sources, drought status, wastewater reuse, and the key water issues facing the city.
Rock Springs
Rock Springs, WY water profile — supply sources, drought status, wastewater reuse, and the key water issues facing the city.
Sheridan
Sheridan, WY water profile — supply sources, drought status, wastewater reuse, and the key water issues facing the city.
Key issues in Wyoming
Colorado River
The river that supplies 40 million people has lost roughly a fifth of its flow since 2000, forcing a renegotiation of how seven states share the water.
ExploreAgricultural Demand
Agriculture accounts for the majority of consumptive water use in the West, making farm efficiency and water markets central to any supply solution.
ExploreDrought
Much of the American West is in a multi-decade dry period that researchers describe as the most severe in over a millennium, reshaping how communities plan for water.
ExploreAnalysis featuring Wyoming
Where Americans Use the Most Water
The states with the highest per-capita water use are clustered in the arid West — and the reasons say more about irrigation and lawns than about long showers.
Read analysisThe 2026 Colorado River Reckoning, Explained
Seven states must agree on how to share a shrinking river after 2026. Here's what's at stake for 40 million people.
Read analysis