N.B. Progressive Conservatives want Fredericton's Princess Margaret Bridge closed for inspection after a 10-kilogram chunk of concrete fell on Sunday. (CBC)

A Progressive Conservative MLA is calling for the immediate closure of the Princess Margaret Bridge in Fredericton after a 10-kilogram chunk of concrete fell off the structure on Sunday night.

Although a vehicle was passing underneath at the time, no one was injured. But the incident has people in the area wondering if the aging bridge is safe.

Carl Urquhart, the Opposition's public safety critic, is one of those who is demanding that the province do something to reassure people that the busy bridge is safe.

"I feel the bridge right now has to be shut down and stopped and immediately tests be done on it," he said.

Construction started on the 1,098-metre bridge that crosses the St. John River in 1957 and it opened in 1959.

Transportation Minister Denis Landry told reporters on Tuesday that until the piece of concrete fell from the 52-year-old structure, he didn't think there were any problems.

Now he said he's considering shutting down the crumbling sidewalks.

"If there is a need to close the sidewalks, we will do it," he told reporters.

Area residents worried about bridge safety

On the south side of the bridge, near where the concrete fell, is a busy road that leads to the city's downtown.

Heather Cameron lives near the Princess Margaret Bridge and said she was alarmed when she heard about the concrete falling.

"Anyone like myself that travels over the bridge every day, or under the bridge, is obviously going to be worried," she said.

The provincial government put weight restrictions on the bridge last November. And an engineering report conducted earlier this year said it needed urgent repairs.

Norm Clouston, the district engineer for the Department of Transportation, said closing the bridge is unnecessary. He said engineers were on site Sunday night and made the necessary repairs.

"The public should be assured that it is safe and we will be monitoring it to make sure it doesn't happen again," he said.

The province has announced $12 million will be spent on repairs for the Princess Margaret Bridge.

The department opened the tenders on April 28 and there were four bidders interested in doing the bridge work. The department is reviewing the submissions and is expected to award the contract within the next few weeks.