Tucson
Tucson, AZ water profile — supply sources, drought status, wastewater reuse, and the key water issues facing the city.
tucson city of
groundwater (wells) · local government · PWSID AZ0410112
Below EPA's 15 ppb lead action level at last testing.
Source: EPA Safe Drinking Water Information System (SDWIS) · 2026 Q1
Tucson is a major U.S. city and the 2nd-largest in Arizona, home to roughly 531,641 residents. Tucson's drinking water comes largely from the same regional sources that serve Arizona: Colorado River, groundwater, and Salt & Verde rivers.
As elsewhere in Arizona, the central challenge is colorado river. A national leader in reuse — Scottsdale has demonstrated direct potable reuse — even as Colorado River cuts and groundwater limits constrain growth around Phoenix.
Arizona reuses an estimated 52% of its treated wastewater and maintains established reuse programs; Tucson tracks moderate to severe drought conditions on the U.S. Drought Monitor scale.
Explore the Arizona profile for statewide context, or dig into the water issues shaping Tucson below.
Pima County water quality
Source: EPA SDWIS · 2026 Q1
At a glance
- Population ~531,641 (2nd-largest in Arizona)
- Primary sources: Colorado River, groundwater, and Salt & Verde rivers
- Drought: moderate to severe conditions
- State reuse rate: ~52% of wastewater
Statewide drought history
% of Arizona in severe+ drought (Severe (D2) now).
Source: U.S. Drought Monitor
Common questions
Is tap water safe in Tucson?
Tucson's largest water system, TUCSON CITY OF, serves about 732,906 people. EPA records show 0 health-based violation(s) since 2016 and a most-recent 90th-percentile lead level of 0.6 ppb (EPA action level is 15 ppb). Always check your own provider's annual Consumer Confidence Report.
Where does Tucson get its water?
TUCSON CITY OF draws primarily from groundwater (wells), part of Arizona's supply from Colorado River, groundwater, Salt & Verde rivers.
Related water issues
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.
ExploreGroundwater Depletion
Aquifers from the Central Valley to the Ogallala are being pumped faster than they recharge, causing land subsidence and threatening long-term supply.
ExplorePotable Reuse
Advanced purification turns treated wastewater into water that meets or exceeds drinking-water standards — increasingly essential in water-stressed regions.
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.
Explore