Iao Aquifer: County seeks all unallocated water

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WAILUKU - The Department of Water Supply made its bid for all the unallocated water in the Iao aquifer and the Iao high-level aquifer Tuesday.

If it persuades the state Commission on Water Resource Management, it could gain access to 3.1 million gallons a day of water, or in excess of 10 percent more than current consumption in Central and South Maui.

Two Waihee farmers, however, are asking for 450,000 gpd from the same bucket.

The requests by the county and farmers would bring the total withdrawals to more than the Iao aquifer's sustainable yield of 20 million gallons per day, a threshold set to protect the water source from damage by overpumping.

"This is the first time the commission has ever done this," said Roy Hardy, chief of the groundwater branch of the commission. He pointed out that in every previous allocation of well permits in designated aquifers, the requests totaled to less than the sustainable yield.

That is far from the case in Iao Valley, the most convenient aquifer on Maui.

If the county got permits for virtually all of the 20 mgd, it would not necessarily gain all 3.1 mgd on top of what it has now. The sustainable yield is a legal maximum, but prudent management of the overstressed aquifer might induce the department to take less. One of the arguments that Jeff Eng, the director of water supply, made at the hearing was that the county would be a better steward.

Eng noted that he previously worked for a private water company.

"Private companies do not provide sensitive stewardship," he said. "All they care about are greater earnings per share and dividend payments."

Farmers Bryan Sarasin and John Varel contended that farming is a reasonable and beneficial use as well.

"I am trying to live a self-sufficient lifestyle," said Sarasin, who wants 51,000 gpd in order to operate a nursery on 0.85 acres with his son. Varel originally asked for 41,000 gpd to irrigate 350 acres of macadamia orchards and fruits and vegetables.

At Tuesday's hearing, he amended that to 400,000 gpd. The commission staff, using its own irrigation formula, had noted that it thought 41,000 gpd was a very low estimate for 340 acres of mac trees. Varel said that when he submitted his request, he did not have a model for mac trees. Now he has one and estimates he needs more.

He said he has lost 10 percent to 20 percent of his trees to drought in the past two years.

According to the State Water Code and Hawaii Supreme Court rulings, there is a hierarchy of uses in a water management area, which Iao has been since 2003. Public trust uses have first claim, starting with protecting the resource itself.

For many years, the department resisted designation of Iao aquifer, but five years ago, then-Mayor Alan Arakawa shifted course. With the county no longer objecting, the commission quickly designated the aquifer, which meant that existing users had a year to submit requests to keep using what they had.

The county had been allocated slightly more than 17 mgd, although it had been taking more than that from Shaft 33, the most productive single well in the area.

It had also been permitted to take 2.4 mgd of "perched" or "diked" water from the high-level aquifer. This is water at higher elevations that would migrate down to the basal aquifer except that it is impeded by lava dikes.

This water is not counted against the 20 mgd sustainable yield, but the commission is involved because of the interaction between perched water, which feeds into Iao Stream. The commission will soon have to determine permanent instream flow standards, taking account of the flow from the dike system.

The commission has chosen to treat the stream, the dike aquifer and the basal aquifer as one system.

In a contested case known as Na Wai Eha, it is deciding what flow levels should be maintained in Iao Stream. Withdrawals from the Iao Tunnel, which is the diked water, will be considered in that.

The department had earlier asked for 1.4 mgd of perched water and now wants a total of 2.2 mgd. Eng said the county has been taking that water since the 1930s and has often taken 2 mgd or more. Today, 350,000 to 400,000 gpd is spilling over from the intake and moving unmeasured and unpermitted into a private ditch, he said.

In the hierarchy of uses, domestic uses are among the public trust uses that take precedence. New agricultural uses would fall in the "all other" nonpublic trust claims at the end of the line.

After listening to Hardy's summary of the rules that the commission operates under, Sarasin and Varel sounded discouraged about their chances.

Sarasin said that if he had known he would have to get a withdrawal permit separately from a drilling permit he might not have spent thousands of dollars to drill earlier this year. Varel said his costs were "in six figures" and that he thought there was something wrong with a system that allows the commission to issue a drilling permit without promising to allow use of the water.

The county's requests are for four locations. They are:

* Iao Tank Well, 500,000 gpd already permitted, 800,000 gpd more requested.

* Mokuhau Well No. 3, 2 million gpd now, 600,000 gpd more requested.

* Waikapu Tank Well, 400,000 gpd permitted, 900,000 gpd more requested.

* Iao Tunnel-Kepaniwai, 2.4 million gpd permitted, 1 million gpd more requested.

Because objections were made to all six permit requests, a public hearing was required. The commission has 180 days from the acceptance of the completed request to act. That means the first decision will be due in late January.

* Harry Eagar can be reached at heagar@mauinews.com.