St. Louis
St. Louis, MO water profile — supply sources, drought status, wastewater reuse, and the key water issues facing the city.
st louis city pws
surface water (rivers/reservoirs) · local government · PWSID MO6010715
Below EPA's 15 ppb lead action level at last testing.
Source: EPA Safe Drinking Water Information System (SDWIS) · 2026 Q1
With about 315,685 residents, St. Louis ranks as the 2nd-largest city in Missouri and a large city. Water in St. Louis is sourced chiefly from Missouri River, Mississippi River, and Ozark aquifer, the backbone of Missouri's supply.
The defining water pressure here mirrors the state's: aging infrastructure. Major rivers provide ample supply; aging systems are the main vulnerability.
Statewide, Missouri recycles about 4% of its wastewater with minimal reuse programs. Locally, St. Louis faces abnormally dry to moderate drought conditions.
The Missouri state profile covers the regional supply outlook; the issues below detail what's driving St. Louis's water future.
St. Louis city County water quality
Source: EPA SDWIS · 2026 Q1
At a glance
- Population ~315,685 (2nd-largest in Missouri)
- Primary sources: Missouri River, Mississippi River, and Ozark aquifer
- Drought: abnormally dry to moderate conditions
- State reuse rate: ~4% of wastewater
Statewide drought history
% of Missouri in severe+ drought (Moderate (D1) now).
Source: U.S. Drought Monitor
Common questions
Is tap water safe in St. Louis?
St. Louis's largest water system, ST LOUIS CITY PWS, serves about 304,709 people. EPA records show 0 health-based violation(s) since 2016 and a most-recent 90th-percentile lead level of 1.8 ppb (EPA action level is 15 ppb). Always check your own provider's annual Consumer Confidence Report.
Where does St. Louis get its water?
ST LOUIS CITY PWS draws primarily from surface water (rivers/reservoirs), part of Missouri's supply from Missouri River, Mississippi River, Ozark aquifer.
Related water issues
Aging Infrastructure
Much of America's water infrastructure is decades past its design life, leaking trillions of gallons a year and demanding hundreds of billions in reinvestment.
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.
Explore