Olathe
Olathe, KS water profile — supply sources, drought status, wastewater reuse, and the key water issues facing the city.
olathe, city of
surface water (rivers/reservoirs) · local government · PWSID KS2009115
Below EPA's 15 ppb lead action level at last testing.
Source: EPA Safe Drinking Water Information System (SDWIS) · 2026 Q1
With about 134,305 residents, Olathe ranks as the 4th-largest city in Kansas and a mid-sized city. Water in Olathe is sourced chiefly from Ogallala/High Plains aquifer, Kansas River, and Arkansas River, the backbone of Kansas's supply.
The defining water pressure here mirrors the state's: groundwater depletion. Western Kansas is on the front line of Ogallala Aquifer depletion, with some areas already pumped to exhaustion.
Statewide, Kansas recycles about 7% of its wastewater with developing reuse programs. Locally, Olathe faces moderate to severe drought conditions.
The Kansas state profile covers the regional supply outlook; the issues below detail what's driving Olathe's water future.
Johnson County water quality
Source: EPA SDWIS · 2026 Q1
At a glance
- Population ~134,305 (4th-largest in Kansas)
- Primary sources: Ogallala/High Plains aquifer, Kansas River, and Arkansas River
- Drought: moderate to severe conditions
- State reuse rate: ~7% of wastewater
Statewide drought history
% of Kansas in severe+ drought (Severe (D2) now).
Source: U.S. Drought Monitor
Common questions
Is tap water safe in Olathe?
Olathe's largest water system, OLATHE, CITY OF, serves about 143,014 people. EPA records show 0 health-based violation(s) since 2016 and a most-recent 90th-percentile lead level of 11 ppb (EPA action level is 15 ppb). Always check your own provider's annual Consumer Confidence Report.
Where does Olathe get its water?
OLATHE, CITY OF draws primarily from surface water (rivers/reservoirs), part of Kansas's supply from Ogallala/High Plains aquifer, Kansas River, Arkansas River.
Related water issues
Groundwater Depletion
Aquifers from the Central Valley to the Ogallala are being pumped faster than they recharge, causing land subsidence and threatening long-term supply.
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.
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