Mayor Alameda Amends Emergency Proclamation for Aging Hilo Wastewater Plant

Families camping at Keaukaha's Hawaiian Home Lands campground spent hours in water carrying 607,000 gallons of unchlorinated sewage in June 2024 before county workers arrived to post warning signs. That history of failure is precisely why Mayor C. Kimo Alameda signed a seventh amended emergency proclamation on April 2, preserving fast-track contracting authority at the Hilo Wastewater Treatment Plant even as a $337 million reconstruction project is underway.

The proclamation, issued under Hawaiʻi Revised Statutes Chapter 127A and the Hawaiʻi County Code, gives the county the authority to issue expedited contracts, authorize overtime staffing, and bypass standard procurement timelines for interim repairs without waiting for routine council approvals. Those powers are not theoretical: engineers from McGovern McDonald Engineers have warned that the plant's structures and components could fail imminently and before the necessary repairs can be made.

The county awarded a $337 million contract to Honolulu-based Nan Inc. to address the critical infrastructure needs as part of the Hilo Wastewater Treatment Plant Rehabilitation and Replacement Project. That Phase One contract was awarded on December 20, 2024, and is to be completed within five years from commencement of the repairs.

The plant, built in 1994, is the only major municipal wastewater facility serving sewered portions of South Hilo. It treats roughly 3 million gallons of wastewater per day on average and serves about 30,000 residents. It discharges treated effluent through an outfall and diffuser 4,500 feet offshore in Puhi Bay. It has never received a significant renovation.

The record of what happens when the plant fails spans two major incidents. A 2022 discharge sent an estimated 2.2 million gallons of partially treated sewage spilling into the bay, prompting the Hawaiʻi Department of Health to advise the public to stay out of the waters from Puhi Bay to Onekahakaha. The June 2024 investigation focused on a discharge of 607,000 gallons of wastewater into Puhi Bay that entered the bay without undergoing the required chlorine disinfection process. Keaukaha Beach Park sits nearby, and families at the Hawaiian Home Lands campground on Puhi Bay's shoreline said their children were in the water all day before learning through social media that it might be unsafe. Some homestead residents did not see posted warning signs until 3:30 p.m., hours into the discharge. A worst-case plant shutdown or uncontrolled spill today would force health advisories across Keaukaha and Onekahakaha beach parks and threaten the nearshore waters that charter fishing and ocean recreation operators depend on year-round.

In March 2024, the county entered into an Administrative Order on Consent with the U.S. Environmental Protection Agency to repair or replace the facility and address other wastewater infrastructure deficiencies. That order also covers deficiencies at Pāpa'ikou and Kula'imano wastewater treatment plants, with all projects required to be completed by 2035.

The seventh amendment is now the governing instrument that keeps emergency repair authority alive while that clock runs. Accountability for the permanent fix runs through three actors: Nan Inc. holds the five-year Phase One contract; the county holds the obligation under the EPA consent order to reach the 2035 deadline; and Mayor Alameda has directed staff to maintain a sewage spill response and mitigation plan for every critical wastewater location on the island. The original proclamation was signed February 11, 2025. Fourteen months and seven amendments later, the facility's underlying condition remains the central unresolved question.