Waipahu
Waipahu, HI water profile — supply sources, drought status, wastewater reuse, and the key water issues facing the city.
Waipahu is a small but growing city and the 6th-largest in Hawaii, home to roughly 38,216 residents. Waipahu's drinking water comes largely from the same regional sources that serve Hawaii: volcanic aquifers and rainfall catchment.
As elsewhere in Hawaii, the central challenge is groundwater depletion. Island aquifers are the primary supply and are sensitive to both over-pumping and contamination, as the Red Hill fuel crisis underscored.
Hawaii reuses an estimated 12% of its treated wastewater and maintains developing reuse programs; Waipahu tracks no meaningful drought conditions on the U.S. Drought Monitor scale.
Explore the Hawaii profile for statewide context, or dig into the water issues shaping Waipahu below.
At a glance
- Population ~38,216 (6th-largest in Hawaii)
- Primary sources: volcanic aquifers and rainfall catchment
- Drought: no meaningful conditions
- State reuse rate: ~12% of wastewater
Common questions
Is tap water safe in Waipahu?
Waipahu is served by community water systems regulated under the Safe Drinking Water Act. Statewide, 6% of Hawaii's systems have a recent health-based violation. Check your provider's annual Consumer Confidence Report for local results.
Where does Waipahu get its water?
Waipahu draws from the same regional sources that serve Hawaii: volcanic aquifers, rainfall catchment.
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.
ExploreSaltwater Intrusion
As coastal aquifers are over-pumped and seas rise, saltwater pushes inland and contaminates freshwater supplies for cities from Florida to California.
ExplorePotable Reuse
Advanced purification turns treated wastewater into water that meets or exceeds drinking-water standards — increasingly essential in water-stressed regions.
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