Concern that Hawai'i's limited water resources are being overtapped has prompted separate legislation on Maui and O'ahu to limit developers' access to sources of drinking water.

One of the proposed measures would restrict golf course development, and the other would require large-scale projects to obtain verification of water availability.

"We have a limited supply relative to our needs, and we have to have some prioritizing," said Jeff Mikulina, director of the Sierra Club in Hawai'i. He said developers should be required to assume more of the burden for developing water sources instead of letting future generations foot the bill for costly desalination plants and other facilities as water becomes more scarce.

Developers say the restrictions are unwarranted and don't take into account the current status of individual water sources and future prospects for additional water supplies.

State Rep. Brian Schatz, D-25th (Makiki, Tantalus), said golf courses should be a low-priority use of potable water. He is planning to introduce legislation next year that would prohibit golf course development unless nonpotable water is used for irrigation.

The Honolulu Board of Water Supply rules require use of nonpotable water for large landscaped areas such as golf courses, parks, schools, cemeteries and highways, but only if a suitable supply is available. Sources of nonpotable water are brackish water from coastal wells and recycled wastewater.

The City & County of Ho-nolulu has only a single treatment plant — the Honouliuli Water Recycling Facility — capable of providing reclaimed wastewater certified for use in areas commonly used by the public. The facility provides 3.6 million gallons of irrigation water daily to six golf courses in the area and will be providing water to the Navy and Haseko golf courses.

The benefits of using recycled water include significantly lower charges: 40 to 55 cents per 1,000 gallons for golf course irrigation vs. $1.98 per 1,000 gallons if potable water is used.

Schatz said his proposal is a response to last week's decision by the state Commission on Water Resource Management to allow Waiawa Development LLC and landowner Kamehameha Schools to pump 1 million gallons of drinking water per day from the Waipahu-Waiawa aquifer on O'ahu for irrigation of two 18-hole golf courses. The golf courses are part of a 3,700-acre master-planned development of up to 12,000 homes.

Barry Usagawa, principal executive of water resources for the Honolulu Board of Water Supply, said the agency pushed the commission to make sure that as a condition of approval, the developer would be required to investigate alternatives to using potable water for irrigation.

"We want high-quality groundwater ultimately to be used for drinking," Usagawa said. "In reality, we know that can't happen overnight."

In fact, the Central O'ahu wastewater treatment plant in Wahiawa, closest to the Waiawa development, is years away from being able to provide recycled effluent clean enough for irrigation.

Schatz said it's "offensive" and "just plain absurd" for officials to approve the use of drinking water for golf courses while asking that consumers cut back on their own consumption.

A similar bill introduced in the last session did not survive.

SAVE IT OR USE IT?

David McCoy, president of Waiawa Development, part of the Gentry Cos., said it's unreasonable to institute a blanket ban against all golf courses that do not have access to nonpotable water sources. He said water use should be considered case by case, depending on the condition of the aquifer in question.

In the case of the Waiawa development, the water commission's decision was logical, he said.

"There isn't a problem at (the Waipahu-Waiawa) aquifer," McCoy said. "The water's just sitting there, so why not use it?"

The commission said the aquifer has a sustainable capacity of 104 million gallons per day, with 56 million gallons per day in use now.

Mikulina described using groundwater for golf course irrigation as "ridiculous" and short-sighted.

"They are narrowly looking at golf course needs today and not looking at the entire project, which will require many, many millions of additional gallons of water," he said. "The larger scheme is: What are the other needs in Central O'ahu?"

Irrigation of new golf course developments has become a concern on the Big Island as resort projects spread across the dry Kona coast. Hawai'i County water official Glenn Ahuna said requiring use of nonpotable water for irrigation is a good idea, when it's available.

He said it's more cost-effective for the counties than using drinkable water, although perhaps more costly to developers to maintain separate systems for potable and nonpotable water.

"For us it's a wasted process," said Ahuna, head of the Department of Water Supply's Engineering Division. "It would save potable water for more people to use domestically and make water available for other developments than golf courses."

Maui County is far ahead of other Hawai'i counties in establishing an extensive program that requires developments within a certain distance of wastewater treatment plants to use reclaimed effluent for irrigation. The incentive to businesses is a much cheaper price for recycled water than for potable water.

Maui, instead, is struggling with how to allocate more finite groundwater supplies than what's available on O'ahu.

High withdrawals at the 'Iao aquifer, which serves the island's most populated areas of Central and South Maui, led the state water commission in 2003 to take over management of the resource from the county.

VISIONARY OR PERILOUS?

Councilman Dain Kane of Wailuku is proposing county legislation that would require developers, at an early stage in the approval process, to get written verification from the Maui water director that a "long-term reliable source of water" is available for their projects.

Kane said his proposal would change Maui's longstanding planning and land-use policies that he claims have allowed growth to dictate water development. "It's always been up to the water department to find new sources to accommodate development," he said.

Instead, according to Kane, the availability of water should be informing land-use and planning decisions.

Kane said he purposely submitted a proposed ordinance that does not contain a lot of specifics, including the definition of "long-term reliable supply of water" and how big projects would have to be before they are subject to the verification requirement. However, he said, small family subdivisions would be exempt.

Thomas Cook, incoming president of the Maui Contractors Association, said the measure would have a grave impact on construction on Maui. He said more data on the island's water resources and projections are needed before any serious discussion can take place on Kane's bill.

"The intentions are good, but it would be very disruptive to the financing of projects if the council sent that message out. It sounds like a moratorium," said Cook, who also heads general contractor TMC Contracting.

He said the contractors association meets regularly with county leaders to discuss new water source development and improvements to the existing system that would make more water available.

D. Kapua Sproat of Earthjustice, a nonprofit environmental law firm, said proposals by Kane and others to link development on Maui to water resources are "visionary" and provide a "reality check" in the face of a looming water crisis.

"As people who live on an island, we have to live within our means," she said.

Sproat said a similar bill recently enacted by California, known as the "show me the water" law, requires up-front screening of water availability for large projects. The law requires a 20-year outlook in determining the long-term reliability of water supplies.

Sproat said the law has proven effective and reduced lawsuits over water availability because developers learn early in the planning process whether adequate supplies will allow them to proceed.

Reach Christie Wilson at cwilson@honoluluadvertiser.com.