State Water Commission Implements Emergency Conservation Measures for Pearl Harbor Aquifer
The state Commission on Water Resource Management voted unanimously Tuesday to implement emergency conservation measures for the Pearl Harbor aquifer, citing concerns over declining water levels and potential contamination risks that could affect hundreds of thousands of Oahu residents.
The emergency designation allows the commission to impose immediate restrictions on new water use permits and requires existing users to implement conservation measures within 30 days. The Pearl Harbor aquifer serves communities from Aiea to Waipahu, including Joint Base Pearl Harbor-Hickam and surrounding residential areas.
“We’re seeing sustained declines in water levels that haven’t been recorded since the 1990s drought,” said Commission Chair Suzanne Case during Tuesday’s meeting at the Kalanimoku Building. “This is not a decision we make lightly, but the data shows we need to act now to protect this critical resource.”
Water levels in monitoring wells have dropped an average of 8 feet over the past 18 months, according to commission data. The decline has been attributed to increased demand from population growth, reduced rainfall, and ongoing concerns about contamination from the Navy’s Red Hill fuel storage facility.
Immediate Impact on Residents
The emergency measures don’t impose immediate restrictions on household water use, but they do halt new development projects that would significantly increase water demand. Commercial users consuming more than 25,000 gallons daily will be required to submit conservation plans within two weeks.
The Honolulu Board of Water Supply, which serves most of Oahu, draws about 40% of its supply from the Pearl Harbor aquifer. BWS officials said they’ve been working with the commission for months to address the declining levels.
“We’ve already implemented voluntary conservation measures and increased pumping from other sources,” said BWS Manager and Chief Engineer Ernie Lau. “Our customers won’t see immediate impacts, but this emergency designation gives us additional tools to ensure long-term sustainability.”
Red Hill Contamination Concerns
The emergency declaration comes as the Navy continues defueling operations at the Red Hill Underground Fuel Storage Facility, following contamination of the Navy’s water system in 2021 that sickened thousands of military families. While the fuel leak didn’t directly impact the civilian water supply, hydrogeologists have warned that continued operations pose risks to the entire aquifer.
Environmental groups have long advocated for stronger protections of the Pearl Harbor aquifer, which sits just 100 feet above the massive underground fuel tanks. The Sierra Club of Hawaii called Tuesday’s action “long overdue but necessary.”
“This aquifer provides drinking water for a third of Oahu’s population,” said Wayne Tanaka, director of the Sierra Club of Hawaii. “The commission is finally acknowledging what we’ve been saying for years – that this resource is under serious threat and needs immediate protection.”
Developer Pushback Expected
The emergency measures are likely to face challenges from developers who have projects in the pipeline. The Building Industry Association of Hawaii has argued that water restrictions could exacerbate Oahu’s housing shortage by limiting new residential construction.
Several major developments in the Ewa Plain and West Oahu corridor could be affected, including portions of the Hoopili and Koa Ridge master-planned communities. Developers with existing water commitments may need to demonstrate additional conservation measures to proceed.
The commission’s action also affects agricultural users in the region, including farms in the Waipahu and Waipio areas. Agricultural exemptions exist for certain crops, but large commercial operations will need to show they’re maximizing water efficiency.
Looking Ahead
Commission staff will review the emergency designation every six months, with the first assessment scheduled for March 2024. The measures could remain in place for several years depending on rainfall patterns, aquifer recovery, and progress on alternative water sources.
The BWS is accelerating plans for recycled water projects and exploring additional groundwater sources in other parts of the island. The utility is also considering mandatory conservation measures if conditions worsen.
For Honolulu residents, Tuesday’s action serves as a stark reminder of Oahu’s water vulnerability. The island relies entirely on groundwater and rainfall, with no option to import water from outside sources like many mainland cities.
The commission will hold a public hearing on the emergency measures next month, giving residents and businesses a chance to comment on the restrictions. In the meantime, officials are urging voluntary conservation as the best way to protect one of Oahu’s most critical resources.
