5 US Cities with Cleanest Air and Water

3. Cheyenne, WY

Population: 100,863

Annual Particle Pollution (2019-2021): 4.1µg/m3

Cheyenne often benefits from clean air quality due to its location in the open spaces of Wyoming. Overall, 70% of water in the city comes from mountain streams. This water undergoes testing throughout the year due to in-line instruments. The contaminants detected in the 2022 water quality report met the EPA’s drinking water guidelines.