MAHWAH, N.J. (CBSNewYork) — Could drastic changes be coming to some New Jersey towns?

That’s what some residents said they fear after the appearance of thin plastic pipes along major roads.

As CBS2’s Dave Carlin reported, in late spring the slender pipes started popping up on power poles in Mahwah, Montvale, and Upper Saddle River.

Pole by pole, pipes and string encircle wide areas to bring freedoms on every Sabbath for orthodox Jews.

“There are over 200 eruvs in metropolitan areas in North America,” Rabbi Adam Mintz said.

Mintz is an Eruv expert.

Manhattan is home to the world’s most complicated, and smaller towns with them include Monsey in Rockland County.

With an eruv, orthodox Jews can carry things and push baby carriages on the Sabbath, because the symbolic fence makes their entire community a Jewish backyard.

“If you’re a young orthodox Jewish family, you’re going to move to a community that has an Eruv,” Mitz said.

Some people in the new eruv towns like members of the group Mahwah Strong, worry if they build it, they will come, and might — as they put it — invade.

They worry orthodox Jews will come in a big wave, put their kids in private school, which they fear might cause public enrollment and funding to drop, while keeping their lives separate from others in the town.

“I don’t really like the idea of building a community within our community,” Tracey Manny said.

“The community should be open to everybody, but at the same time if a large group is looking to take it over that’s an unfair situation,” Rich Dakin said.

The group in charge, Rockland Eruv has an address at a P.O. box in Monsey.

CBS2 reached out by email, but did not hear back.

“We wish the fear was not there, but you can’t deny the fact it is a component of this conversation, it’s a very sensitive issue,” Mahwah Mayor Bill Laforet said.

Laforet said the eruv was built without town approval because town approval was not required.

Electric companies allowed eruvs after several municipalities tried and failed to block them in court.

“This has been argued before,” Mintz said, “And they lost.”

Laforet scoured the town’s laws, and found a possible loophole.

The town of Mahwah considers the poles that comprise the eruv to be signs in violation of a town ordinance.

“We believe that those are not just plastic pipes on the telephone pole, but in fact they are instruments that attract your attention to direct you to stay within the perimeter of the eruv,” he said.

Whether you can call them signs to get them removed, may ultimately be decided by a judge.

A public meeting on the issue is scheduled for 7:30 Thursday night in the senior center behind Mahawah town hall.