HILO — West Hawaii is currently using less than 40 percent of what scientists have determined is the sustainable yield of water in the Keauhou Aquifer system. If current population growth trends continue, that amount will top 60 percent by
HILO — West Hawaii is currently using less than 40 percent of what scientists have determined is the sustainable yield of water in the Keauhou Aquifer system. If current population growth trends continue, that amount will top 60 percent by 2035.
That’s the conclusion of a draft report created for the county Department of Water Supply that was discussed at a Water Board meeting Tuesday. The updated plan follows a February ruling by the state Commission on Water Resource Management denying a petition by the National Park Service to impose stricter regulations on taking water from the aquifer.
The update of the plan will be the topic of a public hearing at the Water Board’s May 23 meeting in Kona before being sent to the County Council and then to the Commission on Water Resource Management.
“It may have been a 15-minute presentation, but it was two and a half years in the making,” said Water Department Manager/Chief Engineer Keith Okamoto. “It’s a document we are committed to follow.”
The aquifer system stretches from Makalawena Beach to north of Kealakekua Bay and includes Kaloko-Honokohau National Historical Park.
The document establishes a comprehensive plan for the use of water resources in the area. Among other things, the update includes county plans to reduce reliance on wells lower in elevation and offset existing needs and future demand with more high-level sources of water.
Consultant Lance Fukumoto of the Honolulu-based Fukanago and Associates showed two scenarios predicting draw-down of water and how close the scenarios would come to the 38 million gallons a day considered a sustainable yield of water or the 28 mgd, 90 percent of the sustainable level, that’s considered the caution line.
“Both scenarios are well below the 90 percent (threshold) of sustainable yield,” Fukumoto said.
He said the move by the county Department of Environmental Management to create quality reuse water for irrigation will further protect the potable water source. The county will also promote water conservation measures to reduce water use.
Board member Leningrad Elarionoff questioned how realistic water conservation plans such as removing fountain grass really are.
“Should it be based on something reasonable or practical or this far-out dream,” he asked.
The county also plans to send well permit applications to the non-regulatory Aha Moku system for review and recommendations for the protection of traditional and customary practices that might be affected by the application in question.
Board member Kanoe Wilson questioned whether contacting the Aha Moku representatives goes far enough in determining lineal families who might be affected by future well-drilling. She was assured the Water Department would go further, but it wasn’t necessary to put it in the plan that had already won approval from the state.
On the web: Visit https://www.hawaiidws.org/ and click on “Power Point for DWS Public Meeting regarding Water Use and Development Plan — Phase 2 Update”
