Almost every day on Oahu a water main break spews water onto the streets and shuts down traffic, while leaking pipes throughout the islands contribute to millions of gallons of lost drinking water.

Yet, year after year, the Hawaii Department of Health has failed to spend tens of millions of federal dollars earmarked for shoring up Hawaii’s drinking water infrastructure, according to the U.S. Environmental Protection Agency.

The funds, which are matched 20 percent by the state, are deposited into Hawaii’s Drinking Water Revolving Fund and loaned to the counties to make repairs.

As of the end of last year, $100 million in federal and state funds sat unspent, according to the EPA, which is now threatening to stop funneling federal dollars to the state, or even take some of it back, if the Health Department doesn’t make major improvements in its management of the fund.

“If they can’t, frankly, get it together and begin running the program in a way that’s making good use of the money, then we have the capability of taking money back and giving it to another state,” said Michael Montgomery, director of the EPA’s Region 9 water division, which oversees the Pacific Southwest and Hawaii.

The state estimates that about $1 billion in repairs are needed over the next two decades to keep Hawaii’s drinking water systems functioning and the drinking water safe.

In March the EPA approved a series of corrective actions that the Health Department says it’s working to implement over the next two years to retain its funding and remain in good standing.

An EPA review of the program found that the Health Department was allocating money to projects that weren’t shovel-ready; needed to make bigger loans; and did a bad job of tracking the program’s finances, making it hard to conduct long-term planning.

“The EPA has determined that the DOH does not have adequate personnel and resources to manage the (drinking water fund), nor has the DOH committed and expended all funds in the (drinking water fund) as efficiently as possible and in an expeditious and timely manner, in violation of the terms and conditions of the grant agreements” and federal regulations, according to a notice of noncompliance filed with the state in October.

Congress established state drinking water funds in 1996 to help states comply with the Safe Drinking Water Act, major environmental legislation passed in the 1970s to protect the country’s drinking water.

But Hawaii has struggled to make good use of the fund for at least the past decade, according to EPA documents. Montgomery said that Hawaii ranks fifth from the bottom among all the states when it comes to fund utilization.

During the past six years, Hawaii has used between 71 percent and 86 percent of the federal funds that were available, a rate well below the national average, according to EPA figures. In 2014 the state used 85 percent of its federal funds, up from 75 percent in 2013. As of 2014 the national average was 93 percent.

On a positive note, Montgomery said Hawaii has done a good job of complying with the Safe Drinking Water Act and that “in the near term, drinking water in Hawaii is pretty safe compared to other states.”

But he noted that in the long run, Hawaii’s infrastructure is suffering and the state is losing out on jobs.

“It’s not good,” said Montgomery. “You don’t want to be the one state that is failing to spend federal dollars that you automatically get. … It’s lost economic opportunity.”

Joanna Seto, head of the Health Department’s Safe Drinking Water Branch, said that her department is already doing a better job of lending out the federal funds and is about to launch a new project and financial tracking system that will help it better manage the loans and grants.

This year the department finalized eight loans worth $48.6 million, she said. In 2016 the Health Department expects to execute 11 contracts worth $69.8 million.

The department has identified more than 100 priority projects for the 2016 fiscal year.

Hawaii’s Health Department also commissioned its own study on the fund, which was completed by Northbridge Environmental Management Consultants, based in Washington, D.C., in October.

Seto said that the department is working to implement the recommendations of that report as well.

The Northbridge report, which also evaluated a similar fund called the Clean Water State Revolving Fund, reiterated many of the EPA findings while also noting that the Health Department has been hamstrung by the bureaucracy of other budget and accounting departments within the state, making it hard to quickly issue loans.

The report also highlighted “a disconcerting lack of collegiality” among staff working in the Health Department’s water branches, which could hinder improvements.

“Perceived confusion or disagreement about the roles and responsibilities of staff has created long-standing conflict and low morale among staff and resulted in operational inefficiencies and substandard program performance,” according to the report’s executive summary.