Oahu residents are asked to reduce water use

The Honolulu Board of Water Supply on Thursday called on all Oahu water users to voluntarily reduce consumption by 10% — a consequence of the loss of a key source of city water in the aftermath of Navy water contamination by fuel from its Red Hill fuel storage facility.

“We need to reduce overall island demand to protect our groundwater resources from depleting,” BWS Manager and Chief Engineer Ernest Lau said in a news release. “This is necessary to ensure that Oahu’s drinking water supply remains healthy and sustainable over the long term. When we shut down our Halawa Shaft due to the Navy’s Red Hill crisis, we knew that having to ask for voluntary conservation was a possibility. We had hoped we could avoid this. Unfortunately, we are in a difficult situation not of our own making.”

At a news conference Thursday, Lau and BWS officials requested in particular that metro Honolulu’s 400,000 residents and Aiea’s 20,000 residents, as well as area businesses, schools, hospitals and government agencies, immediately reduce their water consumption.

Lau said the reason is the loss of supply due to closure of the city’s Halawa shaft, which normally provides 20% of potable water to the metropolitan Honolulu region from Aiea in the west to Hawaii Kai and Kalama Valley in the east.

“Right now this situation is due to the Red Hill crisis,” Lau said. “If the Halawa shaft was online, we wouldn’t have to (ask this).”

The situation was exa­cerbated by February’s low rainfall, which was only 51% of normal, he said. Looking ahead to summer, typically Hawaii’s driest season, demand could overtake supply.

In addition, there is a risk that over-pumping to meet demand could compromise water quality, Lau said, adding, “The primary thing that we track very closely is the saltiness of the water.”

Extra pumping has already resulted in the doubling of the levels of salt, or chloride, in the past two weeks in the artesian wells at the BWS Beretania Street station, said Kevin Ihu, program administrator in the water systems management division. The Beretania station “is one of our biggest sources,” he said.

Pumping at the Beretania station immediately had to be reduced to avoid tainting the aquifer “by pulling up too much salt into the fresh water,” Lau said, adding that only Beretania had seen a chloride spike “so far.”

The Pentagon on Monday announced the Department of Defense will permanently shut down and defuel the Navy’s massive fuel tank facility that leaked petroleum into the Navy’s drinking water system serving approximately 93,000 people.

“We know that below the fuel tanks and near the fuel facility, the groundwater aquifer is contaminated with fuel,” Lau said.

“We don’t know how it’s moving with the groundwater, but we suspect there is movement across Halawa Valley,” thus the three wells were closed to prevent possible pollution throughout Oahu’s aquifer, he said.

Five other city wells near the Navy shaft are being tested weekly, and contamination by fuel has not been detected, he added.

While expressing the board’s reluctance to have to ask the public for voluntary reduction in water use, Lau did not rule out the possibility of mandatory measures if necessary.

“If everyone cuts back their usage by 10% now, we may not have to resort to progressively restrictive mandatory conservation later in the year,” he said, noting the only time that had happened in his 40 years at BWS was in the late 1980s when mandatory restrictions during a severe drought resulted in a 20% drop in water use.

In winter, BWS water sources usually produce about 130 million gallons a day. In summer, that number rises with demand to about 150 million gallons a day — an increase attributed mostly to irrigation and “outdoor nonessential uses,” said Barry Usagawa, BWS program administrator in the water resources division.

The state Department of Land and Natural Resources announced Tuesday the U.S. Drought Monitor shows all of the main Hawaiian Islands experiencing at least moderate drought this winter.

January had average rainfall, and while December rainfall intake was 276% of normal, a lot of that rain ran off without recharging the aquifer, Lau said.

Even if Oahu does get some rain now, it will be inadequate to replenish the aquifer without reduction in demand now.

Otherwise, Lau said, summer could see localized areas experiencing disruption in water service, including lower water pressure especially in areas of higher elevation, and water shortages.

Top water users that BWS is working with include government agencies such as the Department of Education, said Kathleen Elliott-Pahinui, BWS chief information officer.

“If we each save a little water, together we’ll save a lot,” Lau said.

“We need everybody’s kokua,” he added.

TIPS TO CONSERVE

Noting that March 22 is World Water Day, which focuses on groundwater this year, the Board of Water Supply is urging Oahu customers to be mindful of their water use in their daily activities by adopting practices that avoid water waste.

The department suggests following measures such as those posted online in the BWS’ “Seven Easy Ways to Save Water” at boardofwatersupply.com/7ways.

Tips include:

>> Watering lawns and gardens before 9 a.m. or after 5 p.m.

>> Taking shorter showers.

>> Not letting faucets run while washing dishes or brushing teeth.

Other educational and informational resources on the agency’s website include signing up for high-use and leak detection alerts.

Rebates are also available for residential and commercial customers who purchase rain catchment barrels and certain appliances bearing the U.S. Environmental Protection Agency’s Energy Star and Water Sense labels.