Wahiawā Wastewater Treatment Plant

  • Drinking water is sourced from the aquifers in areas of the Koʻolau & Waiʻanae Mountain ranges and pump to your home via water mains.

  • Untreated wastewater is conveyed through sewer mains from Wahiawa Town, Whitmore Village, and the U.S Naval Computer and Telecommunications Area Master Station. The wastewater then arrives at the Wahiawa Wastewater Treatment Plant where it receives tertiary treatment, the highest level of wastewater treatment.

  • The entirety of the wastewater received at the facility is disposed of via an outfall that discharges into the Wahiawa Reservoir. The outfall is located at the bottom of the reservoir at approximately 44 feet below the surface.

  • Treated wastewater flows through an outfall pipe and is discharged into receiving waters (the Wahiawa Reservoir, a fresh water body).

  • Oʻahu's Drinking Water Sources

    Oʻahu relies solely on underground water sources for drinking water which are all dependent on three natural elements: northeast trades, high mountain ranges, and the island's geological landscape. The NE tradewinds drive clouds filled with moisture inland, the high mountain ranges (Koʻolau mountains and Waianae mountains) capture and force moisture-filled clouds to higher elevations which causes rainfall on watershed areas. The Hawaiian Island geological landscape serves as a natural filter and underground storage system of water. Rainwater percolates into the earth, filtered by volcanic rock, and stored in aquifers. The aquifers are an underground freshwater reservoir storage from which the Board of Water Supply sources water to deliver to homes. Water is pumped from a network of shafts, water tunnels, and many wells located all over Oʻahu, (except for the North Shore area) and conveyed to homes through mains, booster systems and reservoirs.

    Oahu's Drinking Water Sources
  • Wahiawā Wastewater Treatment Plant Facility
    Wahiawā Wastewater Treatment Plant
  • Outfall Map
    Outfall Map

Do You Know What Happens After You Flush?