The Anoka County Board has rescinded a 23-year-old policy supporting the “prevailing wage” on county-funded construction projects, angering union officials who said Tuesday that they’ve legally challenged a decision that they claim was made without public notice.

Representatives from more than a dozen Twin Cities unions, saying they were deprived a public hearing, gathered in the County Board room to challenge the board’s 4-2 vote on Feb. 12.

The two board members who voted against rescinding the provision said they weren’t aware that it was to be discussed until the morning of the vote. Board Chairwoman Rhonda Sivarajah, however, said all commissioners were notified of the amended agenda; another county official said the notice was sent the afternoon before the meeting.

Prevailing-wage policy requires that employees on construction projects be paid at rates comparable to those that have been paid for ­similar work in the area. By repealing its policy, the county can award county-funded projects to the lowest bidder. There are state and federal prevailing-wage laws that apply to federally- and state-funded projects, including county projects that involve such funds.

“We’re concerned that there was no public notice, no chance to give our side of the story,” said Dan McConnell, business manager of the Minneapolis Building and Construction Trades Council.

McConnell wrote to Anoka County Attorney Tony Palumbo, asking whether the board violated the law by not giving public notice. Palumbo said a member of his staff is investigating the matter.

Commissioners Carol LeDoux and Jim Kordiak, who voted to retain prevailing wage, say the board appeared to give neither of them proper notice of the change in agenda.

LeDoux said she had just returned from a vacation and was given “no notice.” Kordiak said he reads agenda notices the Thursday before Tuesday morning board meetings. He said he learned the morning of the vote that a change in agenda had been sent to his iPad the day before.

“There was no opportunity to comment, no discussion among County Board members,” Kordiak said. “It certainly was a surprise to me.”

Sivarajah said there was ample time for commissioners to consider the proposal.

She also said that concern that the change will take away work from local companies in favor of cheap out-of-state labor is baseless.

“Is a company from North Dakota going to come here for a $75,000 project?” she asked. “I don’t think so.”

Sivarajah said she was miffed by the way local Teamsters leader Ed Reynoso encouraged union members to voice displeasure over the vote. Reynoso, who also is a member of the Metropolitan Council, said union members were urged through text messages to phone the four commissioners who voted to repeal prevailing wage. Those commissioners are Sivarajah, Matt Look, Robyn West and Julie Braastad.

“I learned long ago that you get further with honey than vinegar,” Sivarajah said. “In this county, bullying and intimidation are not acceptable.”

Reynoso said union officials are irked by characterizations of union workers allegedly made by Look, the County Board vice chairman. Look denies making disparaging comments to union members.

“It’s not even believable,” Look said. “Their claims are baseless.”

“I’m for market wage and prevailing experience,” Look said. “I respect their right to disagreement. I certainly don’t belittle them on the phone.”

At Tuesday’s meeting, Look referred to the county’s “fragile” relationship with the Met Council. Look recently sent Reynoso a text message saying that Look had called the governor’s office “concerning the hostile environment” that Reynoso was creating “concerning our most recent prevailing-wage vote.”

He further wrote that Reynoso should “reconsider the inappropriate crossover of your day job and relations that you may have potentially strained.”