Construction at a Brooklyn subway stop aimed at making the station ADA compliant has caused flooding, shattered windows and damaged nearby property, say area residents and business owners.

The work at the Metropolitan Ave./Lorimer St. station in Williamsburg is meant to bring the station up to snuff with new elevators, raised boarding areas, sidewalk curbs and Braille signs, among other improvements. Construction is expected to wrap up later this year.

But as the work proceeds, the complaints roll in.

“This has been an absolute nightmare for myself, neighbors and other fellow small businesses across the Metropolitan, Lorimer and Union vicinity,” said Joseph Franquinha, owner of Crest Hardware, a 61-year-old business upstairs from the station.

“While we’re all understanding and compassionate to the ADA needs of our city, there are right ways and wrong ways of going about it,” Franquinha said. “And this is most certainly the wrong way.”

City Council member Jennifer Gutiérrez (D-Brooklyn) and Assemblywoman Emily Gallagher (D-Brooklyn) called for “immediate intervention” to address neighbors’ concerns in a letter to Jamie Torres-Springer, the president of construction and development for the MTA.

Conditions on the project “are not just a nuisance, but dangerous, and we know that the MTA typically holds their contractors to a higher standard,” said the letter, shared with the Daily News.

“Of course, some nuisance is to be expected around construction, but the MTA’s total disregard of this area has even led to city agencies complaining about the MTA’s lack of communication and coordination,” Gutiérrez said in a statement.

She added that she’s been complaining for months, but that conditions have worsened. “I don’t think we would see this level of neglect in places like Manhattan,” Gutiérrez said.

Franquinha said the construction caused flooding in his building that left tenants without heat or hot water for days.

One day in December, construction crews dumped the water from two big dumpsters that held concrete water into the street, he said.

“It created backflow and came back up the pipes and up Metropolitan Avenue,” he said.

The dark, murky, pungent water, mixed with sewage and with an oily film across the top, leached under the sidewalk and into Franquinha’s basement, the building owner said.

Franquinha pulled on galoshes and grabbed some garbage bags, and got to work cleaning the “disgusting, unsanitary” mess.

“I wouldn’t wish that on my worst enemy, to sift through that … We’re talking a 1500-square-foot basement filled with water 2½ feet high. I mean, that’s a lot of water,” he said.

Lisa Summa, 58, a retired public school teacher who lives next to the construction, said she’s felt unsafe coming home at night because the construction creates a dark tunnel to her door. Late-night work on the project has interrupted her sleep, she added.

“Your home is not your home,” said Summa, a lifelong resident of Williamsburg. “They’re literally in my living room with noise. It’s an unbelievable feeling. We don’t even open our windows because of dirt [in the air].”

Summa and more than a dozen other nearby residents organized the Friends of Lorimer group to challenge the project. “It did feel like the MTA was paying lip service about wanting to be a good neighbor,” she said.

“You can put this elevator, do it well, and also try to cause minimal impact to the community.”

Ivan Garcia, a co-owner of Zona Rosa, a Mexican restaurant on the corner of Metropolitan and Lorimer, said that his business is down 60% since construction began last year, and that he’s had to lay off servers and bartenders.

He blames the construction — it hides the restaurant from view and blocks foot traffic.

“I think it’s the worst year, ever, for us,” he said. “Today is Taco Tuesday. Usually, everyone is here, looking for happy hour. But now, we have nobody.”

Vibrations have caused two-inch-wide cracks in the concrete floor and several broken windows in the restaurant’s building, Garcia said.

Additionally, he said, water has pooled in places it didn’t before on the restaurant’s open roof. Garcia fears that may be a sign that the building’s foundation is damaged.

“They have big machines and then the whole building vibrates — it shakes,” Garcia said.

An MTA spokesperson told the Daily News that crews have been performing limited night work inside the Lorimer St. station, which is allowed since the station is indoors and open 24/7.

The agency has also been made aware of damage to a nearby building, the spokesperson said, and is investigating whether the ongoing construction is to blame.

The work at the Metropolitan Ave./Lorimer St. station is part of a larger effort by the MTA to improve accessibility in its stations, following the settlement of a lawsuit against the agency brought by disability advocates.

The MTA committed last year to making 95% of the subway system accessible. Fewer than a third of the city’s subway stations are now accessible in line with ADA standards.