After more than four years without a functional fire suppression system, repairs at one of the city’s largest bus depots are finally getting done, MTA officials confirmed to the Daily News.

A long-awaited plan to replace a broken underground pipe feeding the sprinkler system at Brooklyn’s East New York Bus Depot has been quietly chugging along for months, sources told The News — and transit officials say they plan for the $7 million repair job to wrap up by the end of the year.

“It’s going well, the project’s on schedule,” Frank Farrell, the MTA’s newly-minted bus boss, told The News. “The target is for the end of the year, to have the whole system up and running.”

Farrell said contractors from Richards Plumbing and Heating Co., Inc. — a Brooklyn firm that has done similar fire standpipe work at Grand Central and the Triboro Bridge — began work in January and is now “fifty to sixty percent” done with the installation.

Sources with knowledge of the depot confirmed to The News this month that work has underway to replace the crumbling pipe with an above-ground loop, while also replacing the thousands of sprinkler heads throughout the building.

“It is a lot of work,” Farrell said. “But, fortunately, it’s not going to affect our bus operations — getting buses in and out of the depot, or maintenance, or any of that — which is key.”

The contract, awarded in August, is for about $6.7 million.

As previously reported by The News, the missing fire sprinkler setup continues to cost the MTA nearly $5 million a year as it pays transit workers overtime to conduct a round-the-clock foot patrol of the facility, looking for signs of fire.

The depot has been without functional fire suppression since 2001, when a leak developed in the underground loop of pipe that feeds the thousands of sprinkler heads scattered throughout the massive facility.

Work crews repaired that leak — but the pipe proved unable to hold the hundreds of pounds of pressure required to prime the sprinklers.

When the pipe ruptured again in July 2022, eight feet beneath a storeroom on the first floor, the MTA began paying bus depot workers overtime to walk the massive facility in a round-the-clock fire watch — a requirement under the fire code when sprinkler or alarm systems aren’t working.

The water line was again dug up and patched, but over the next few years each pressure test revealed a new leak to repair, and the system remained offline.

When The News first reported on the growing cost of fire watch overtime in 2023, MTA officials said a solution could be expected soon.

Agency spokesmen said the pipe would be lined with epoxy in an effort to strengthen it, and then-NYC Transit President Rich Davey told FOX 5 News that his crews were “probably within weeks of fixing it.”

But months later the epoxy plan was scrapped, and the pipe continued to leak.

A plan to abandon the crumbling pipe and replace it with one above ground had first been floated by Farrell’s predecessor, Frank Annicaro, in a March 2023 memo lamenting the estimated $4.8 million in overtime costs.

Farrell also told The News his team is also planning to address the depot’s fire-alarm system — which has also been on the fritz.