Ewa Beach homeowners Charlotte and Yuka Momosea and their neighbors try not to waste water. Yet the community in which they live hasn’t been able to account for over 100 million gallons of the precious resource in the last year.

Recently, the suspected water loss has averaged around 500,000 gallons a day and is believed to be from leaking distribution pipes beneath roadways, with fresh water draining into the porous coral subsurface without a trace.

Another aspect of the troubling situation is a rising water bill delinquency that as of last month hit $2 million for the community developed by Gentry Homes Ltd. around 20 years ago, with 612 single-family residences.

“The amount of water being wasted is unfathomable,” said resident David Tupper. “It’s mind-blowing.”

Residents face an estimated repair bill of $5 million, which breaks down to about $8,200 per household on average, though the expense is expected to be considerably higher because it will likely be financed and repaid slowly.

There also is a strong feeling among homeowners that their water utility pipes should be lasting far longer, and that Gentry or materials suppliers or contractors should be responsible for the problem.

All the affected homes were sold by Gentry between 2000 and 2004 as entry-level housing where two-story single-family residences are close to each other on what is essentially one collectively owned land parcel in the community with four section names — Terrazza, CorteBella, Las Brisas and Tiburon.

Throughout the community, where original home prices were mainly in the $200,000s, roads and underground utilities are owned by the association of homeowners, as opposed to the city, much like a townhome condominium complex. The collective water bill is paid by homeowners through monthly maintenance fees largely between $400 and $500.

Gentry, which has been building homes in Hawaii for over 50 years, said in a statement that it takes extreme pride in the construction quality of all its projects, that all piping materials were on an approved Honolulu Board of Water Supply list, and that all warranties and responsibilities of the developer expired after 10 years.

“Although we at Gentry understand the (homeowner) association’s predicament, Gentry is not responsible to repair or replace any leaking plumbing pipes,” the company said. “Gentry has offered to refer professionals to the association and the management company that could assist in diagnosing and correcting any problems.”

State Rep. Bob McDermott, whose district includes Ewa Beach, has urged Gentry to help homeowners, who in his view shouldn’t be facing major utility repairs within a traditional 30-year mortgage term.

“These are working class families, through no fault of their own, now facing a huge expense,” McDermott said in a July 27 letter to the company. “Their dream home, that they saved for, worked hard and struggled for, has now become a nightmare.”

McDermott said he’s disappointed with the stance taken by Gentry, which has built thousands of homes in Ewa Beach under its Ewa By Gentry master plan, along with homes in Waipio, Kapolei and elsewhere.

“They’re good corporate citizens, generally speaking,” he said. “And they care about Ewa Beach. But their attitude was: ‘too bad, so sad, it’s been over 10 years.’”

Gentry was not willing to say whether other communities are known to be facing similar problems, but the situation presents a cautionary tale that could be useful to other homeowners who share utilities and might not be routinely examining bills for signs of potential problems.

For Terrazza-CorteBella-­Las Brisas-Tiburon homeowners, individual water use isn’t measured. Only two meters exist, and one monthly water bill goes to the community’s property management firm, Hawaiiana Management Co.

Representatives of Hawaiiana and the community association’s board referred comments to the association’s attorney, Maxwell Kopper, who said he could not immediately comment.

According to a copy of the community’s Sept. 3 water bill, monthly water use during the prior 29 days totaled 25.5 million gallons. That was up from 16.7 million gallons in the same period last year, and association management let homeowners know in a recent notice that “normal” historical monthly use is between 6 million and 8 million gallons.

This indicates that the problem dates beyond the last year.

In a recent notice to homeowners, community association management said some major repair work has been underway but that long-term fixes require expert diagnosis work that still needs to be done.

The notice also said the association will be paying only a fraction of upcoming monthly water bills — $97,000 — until usage declines to 10 million gallons a month.

A $97,000 payment would cover about 16 million gallons of water. The association’s Sept. 3 water charge was about $162,000 and its previous unpaid balance was $2 million.

Board of Water Supply officials encourage property owners to examine water volume statistics on monthly bills to identify potential leaks.

The agency also alerts property owners to unusual changes, and has a policy for reducing bills in cases where leaks are documented and fixed.

This policy can provide a customer up to a 50% discount once within a five-year period.

“Our goal isn’t to be punitive,” said agency spokeswoman Kathleen Pahinui. “Our goal is to solve the problem.”

Some Terrazza-CorteBella-­Las Brisas-Tiburon homeowners recall spot repairs to water lines beneath roads being done for years, and said they were surprised that they weren’t alerted to the extent of the trouble long before a notice two months ago explained the projected repair cost and water bill delinquency.

Tupper, who bought a Tiburon home in 2013, said he was shocked by the notice in July.

“It’s such a big problem,” he said. “It’s a catastrophic waste of water.”

The notice explained that homeowners had a choice to collectively take out a loan, which requires majority approval, or face a special one-time assessment that could be around $15,000 for owners of larger homes.

As of Sept. 21, 49.7% of homeowners had agreed to the loan.

The Momoseas, a retired couple who bought their Tiburon home in 2004, said the community shouldn’t be in the position it’s in.

They said they had to back the community association loan but feel Gentry should contribute to the repair cost.

“Somebody went mess up,” Yuka Momosea said.

“Nobody can come up with $15,000,” Charlotte Momosea added. “We’re stuck.”