WILLIAMSBURG — Bridge-and-tunnel traffic has been reversed as less-than-hip Manhattanites now flock to Williamsburg, ruining the scene for locals, residents complain.

Ever since he moved to North Williamsburg a few years ago, Michael Chandler has lost some of his favorite undiscovered bars to hordes of weekend "flipsters."

"They're poser hipsters. They come from the city or from New Jersey to come play hipster for the weekend," said Chandler, 26, of the term. "There's some weird touristy draw... All the cool bars that used to be not crowded are now crowded by weekenders."

The explosive popularity of bars on the Williamsburg waterfront and near McCarren Park — and the opening of higher-end spots targeting tourists and visitors from outside Brooklyn — have spurred such a nightlife shift that many local partiers are avoiding certain blocks altogether when Friday night rolls around.

"You know how it is here — once places become too cool and popular, you ditch them and try to find the next place," laughed Chandler of the local mindset, adding that prices had gone up with the influx of outsiders. "I just like cheap beer."

A two-block strip of Wythe Avenue that features the year-old Wythe Hotel, the 4-month-old nightclub Output Club, the venue Brooklyn Bowl and the bar Kinfolk Studios has transformed so much in the past several months that locals said more visitors than actual Brooklynites were around on the weekends.

"The people who actually live on this block don't go to these places. I don't go to the Wythe, I don't go to Output," said Wythe Avenue resident Kate, 26, who declined to give her last name but said she'd lived on the stretch for the past two years and was dismayed by the changes.

"I have friends who come in from Manhattan to walk around or go to the Brooklyn Flea," she said of the weekly waterfront market. "And I'm like, 'Just because you want your touristy fix one day doesn't mean I can hang out [with you].' I live here all the time."

Meanwhile, a barista at Kinfolk Studios said he and fellow staffers had also seen a shift in recent months that would likely increase with the slated opening of another massive nightclub on the Williamsburg waterfront.

"Especially with Output, the owner wants to keep it underground, so that draws people from the city or people from New Jersey who'd usually go to Manhattan," said the barista, Tom Gastelluh. "It definitely has become a weekender destination...This whole block is bringing more college, fratty guys to the area."

The owner of Output did not immediately respond to calls and emails requesting comment.

But more than just "weekenders," the hotel's opening and the overall publicity about Williamsburg had turned Wythe Avenue into an internationally renowned strip, Gastelluh said, noting an uptick particularly in Spanish and Italian customers at Kinfolk.

Within a few minutes, young Italian and Belgian visitors passed by on Wythe Avenue on a recent afternoon.

"I read Williamsburg is one of the youngest parts of New York," said a 26-year-old Italian, David Barco, "so I came here."

No matter how residents feel about the area's changing demographic, Gastelluh said the "evolution" was inevitable — and mainly positive, particularly for the local economy.

"It's brought more business to us, which is great," said Gastelluh. "So much has happened in the past three months, it'll be interesting to see what happens in the next six."