Maui asked to conserve water
By Christie Wilson
Advertiser Neighbor Island Editor
WAILUKU, Maui — County officials are waiting for word on whether the state will take control of Maui's chief source of drinking water after dry conditions increased pumping at the 'Iao Aquifer above acceptable levels.
Department of Water Supply Director George Tengan said yesterday he had notified the state that the 12-month "moving" average had exceeded the 18 million-gallon-per-day (mgd) trigger set by the state Commission on Water Resource Management.
In a related move, the water department yesterday issued a notice asking residents of South and Central Maui to voluntarily conserve water. The affected areas include Wailuku, Kahului, Kihei, Wailea, Makena, Waihe'e, Ma'alaea, Waikapu, Spreckelsville and Pa'ia.
It was the first time in recent memory that those areas had been placed under voluntary water restrictions. The drought-prone Upcountry region, which relies on surface water, has been under voluntary water-use measures since December.
Peter T. Young, chairman of the state Commission on Water Resource Management, said yesterday he had not received the notice from Tengan and was not ready to comment. Young also heads the Department of Land and Natural Resources.
The water commission had been petitioned by a group of Maui residents to designate the 'Iao and Waihe'e aquifers, which serve the island's most populated areas, as a state water management area. That would have put the commission in charge of all permits to withdraw water.
The entire islands of O'ahu and Moloka'i are state water management areas.
In stopping short of designating the Maui aquifers, the commission in November lowered the 12-month moving average for 'Iao from 20 mgd to 18 mgd, which is 90 percent of its estimated sustainable yield.
Pumping in any given month can exceed the limit as long as the moving average for the preceding 12 months stays below 18 mgd. A moving average is calculated by adding the averages of the preceding 12 months and dividing by 12. Exceeding the 18 mgd limit is supposed to trigger outright designation and state control.
Like much of the state, Maui hasn't gotten much rain this year, and the amount of water taken from the two aquifers — deep beneath the West Maui Mountains — has increased over the past three months.
In April, 18.4 mgd were pumped from 'Iao, according to the water department. In May the number was 19 mgd, and in June pumping increased to 19.4 mgd.
The 12-month moving average last month was 18.06 mgd — just slightly over the 18 mgd trigger.
The Waihe'e Aquifer's sustainable yield is 8 mgd. An average of 3.7 mgd was pumped from the source in April, 4.1 mgd in May and 6.2 mgd in June. The 12-month moving average was 4.5 mgd.
Mayor Alan Arakawa said it was inevitable that pumping levels at the 'Iao Aquifer would exceed the trigger, and he criticized previous county leaders for not taking steps to address Maui's water situation. The water department was managed by the semi-autonomous Board of Water Supply until voters last year decided to place it under the mayor's control.
"It should have been dealt with years ago. We're at the point where something drastic needs to be done ..." Arakawa said. "I have no problem with state designation. They should be responsible."
The mayor said he has been talking with Young and other water commission officials about the water situation and has scheduled an Aug. 7 meeting to present proposals to deal with it.
One problem, he said, is that the county does not have control over the surface water that flows from the West Maui Mountains in streams and a series of ditches that once supported sugar cultivation. He said 50 mgd is available from these surface sources, which are controlled by the state.
He said it's "ludicrous" to expect the county to manage Maui's water resources when it has control of only a portion of those resources.
"If the state refuses to let us have control, then the state should take control ..." the mayor said. "I don't feel that I am capable of managing resources I don't have control over."
Reach Christie Wilson at cwilson@honoluluadvertiser.com or (808) 244-4880.
