The city’s ten-day experimental closure of Dartmouth Street is coming under fire from residents who see it as lacking in both planning and payout.

June 7 marked the beginning of a test by city officials of limited road closures to expand pedestrian areas around Copley Square. Traffic has been barred from Dartmouth Street rerouting those cars to Huntington Avenue and Stuart Street.

The experiment has garnered heavy pushback from civic groups and commuters for increasing the strain on streets already stretched to capacity. The Neighborhood Association of the Back Bay (NABB) was one of the groups consulted before the closure, and strongly advised officials against it.

NABB Chair Elliot Laffer said the move would be highly disruptive and might not provide an accurate picture of what the street looks like year-round.

“NABB was opposed to this when we first heard of it and has been ever since. Dartmouth Street is a vital connector, and the alternative roads have been congested for decades. There was supposed to be a path for emergency vehicles, but I saw just yesterday an ambulance trying to come down Ring Road, all jammed up. It doesn’t take a lot to congest those streets, and that was just at 2:30 in the afternoon,” he said.

That suspicion is shared by Cindy Brown, CEO of Boston Duck Tours.

She says her company wasn’t warned of the closure until an official mentioned it just a day before it went into effect at an unrelated meeting, forcing her drivers to change routes and deal with extra traffic. She says other businesses were put in similar binds.

“We only learned about it a day before it happened. We had to scramble to reroute our tours that normally take Dartmouth, and now there’s traffic |backing up on Huntington Avenue,” Brown said.

“They’re only going to get a small snapshot of the space. It’s a sunny day in June, but there’s nothing going on there in the winter, and they’re not going to be getting any feedback from drivers. Of course, pedestrians are going to say it’s great, they’re not dealing with the traffic.”

City officials have done little to assuage those doubts.

While they’ve been vocal in advertising the event’s programming and asking residents to come give feedback in person, the Boston Planning and Development Agency (BPDA) which is paying for and overseeing the experiment declined to answer questions about what metrics they were measuring to judge the program’s success or failure.

The BPDA was similarly tight-lipped about exactly how much the endeavor is costing the city.

Funding is coming out of the $200,000 reserved for enhancing Copley Square as part of the mitigation for the Winthrop Square project, but spokespersons declined to give figures on how much was being spent on the ten-day experiment and how much is left over for more permanent enhancements.

That said, the project hasn’t been met exclusively with suspicion. State Representative Jay Livingstone was broadly positive, sympathizing with residents’ doubts but cautiously optimistic that the information gathered would be worth the disruption.

“I’m curious to see how pedestrians make use of the space. There’s inconvenience to drivers, there’s potential inconvenience to emergency vehicles that needs to be figured out,” Livingstone said.

“But I'm pleased that Mayor Wu is trying this experiment to determine if we can add public space in Back Bay and improve pedestrian safety, and I look forward to learning how it goes.”

If the city does decide to make some measure of this experiment permanent, it will have to contend with ferocious resistance from neighborhood groups. Just temporarily rerouting traffic already has some hackles raised.

“It all sounds very attractive when you’re walking around that street. But the question is where the cars go. We’ve had discussions about it before, and I understand the feel-good part of it. But it only takes a little bit of extra traffic and the whole road shuts down. Putting more cars on Berkeley is just unacceptable,” said Laffer.