Phoenix
America's fifth-largest city balances Colorado River cutbacks, new groundwater limits on growth, and a long history of recycling water — including to cool the Palo Verde nuclear plant.
phoenix city of
surface water (rivers/reservoirs) · local government · PWSID AZ0407025
Below EPA's 15 ppb lead action level at last testing.
Source: EPA Safe Drinking Water Information System (SDWIS) · 2026 Q1
Phoenix relies on a portfolio of Colorado River water (via the Central Arizona Project), the Salt and Verde rivers, and groundwater. As the first tier of Colorado River shortages took effect, Arizona absorbed some of the largest cutbacks in the Lower Basin.
In 2023 the state announced it would stop approving new housing developments around Phoenix that rely solely on groundwater, after a study found existing demand would outstrip century-long groundwater supplies — a landmark moment linking water limits directly to growth policy.
Reuse is deeply embedded here: treated effluent from Phoenix-area plants has long cooled the Palo Verde Generating Station, the largest nuclear plant in the country, and the region is expanding advanced purification to add a drought-proof drinking supply.
Maricopa County water quality
Source: EPA SDWIS · 2026 Q1
At a glance
- Absorbed major Colorado River shortage cutbacks
- Halted new groundwater-only subdivisions around metro Phoenix (2023)
- Recycled water cools the Palo Verde nuclear plant
- Expanding advanced purification for potable reuse
Statewide drought history
% of Arizona in severe+ drought (Severe (D2) now).
Source: U.S. Drought Monitor
Common questions
Is tap water safe in Phoenix?
Phoenix's largest water system, PHOENIX CITY OF, serves about 1,695,000 people. EPA records show 1 health-based violation(s) since 2016 and a most-recent 90th-percentile lead level of 2.7 ppb (EPA action level is 15 ppb). Always check your own provider's annual Consumer Confidence Report.
Where does Phoenix get its water?
PHOENIX CITY OF draws primarily from surface water (rivers/reservoirs), 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.
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.
ExplorePotable Reuse
Advanced purification turns treated wastewater into water that meets or exceeds drinking-water standards — increasingly essential in water-stressed regions.
Explore