Sioux City
Sioux City, IA water profile — supply sources, drought status, wastewater reuse, and the key water issues facing the city.
sioux city water supply
surface water (rivers/reservoirs) · local government · PWSID IA9778054
Below EPA's 15 ppb lead action level at last testing.
Source: EPA Safe Drinking Water Information System (SDWIS) · 2026 Q1
Sioux City is a small but growing city and the 4th-largest in Iowa, home to roughly 82,821 residents. Sioux City's drinking water comes largely from the same regional sources that serve Iowa: Mississippi & Missouri rivers, Jordan aquifer, and alluvial aquifers.
As elsewhere in Iowa, the central challenge is agricultural demand. Nutrient runoff and nitrate contamination from agriculture are the defining water-quality challenges.
Iowa reuses an estimated 4% of its treated wastewater and maintains minimal reuse programs; Sioux City tracks no meaningful drought conditions on the U.S. Drought Monitor scale.
Explore the Iowa profile for statewide context, or dig into the water issues shaping Sioux City below.
Woodbury County water quality
Source: EPA SDWIS · 2026 Q1
At a glance
- Population ~82,821 (4th-largest in Iowa)
- Primary sources: Mississippi & Missouri rivers, Jordan aquifer, and alluvial aquifers
- Drought: no meaningful conditions
- State reuse rate: ~4% of wastewater
Common questions
Is tap water safe in Sioux City?
Sioux City's largest water system, SIOUX CITY WATER SUPPLY, serves about 85,791 people. EPA records show 5 health-based violation(s) since 2016 and a most-recent 90th-percentile lead level of 2 ppb (EPA action level is 15 ppb). Always check your own provider's annual Consumer Confidence Report.
Where does Sioux City get its water?
SIOUX CITY WATER SUPPLY draws primarily from surface water (rivers/reservoirs), part of Iowa's supply from Mississippi & Missouri rivers, Jordan aquifer, alluvial aquifers.
Related water issues
Agricultural Demand
Agriculture accounts for the majority of consumptive water use in the West, making farm efficiency and water markets central to any supply solution.
ExploreAging 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.
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