Chaudière Bridge, which connects Ottawa's Booth Street with Gatineau's Eddy Street, was closed to both traffic and pedestrians Thursday. (Roger Cote/CBC)

A key commuter link between Ottawa and Gatineau has been closed indefinitely to both vehicles and pedestrians in both directions, causing confusion and extra congestion during Thursday's morning rush.

Public Works Canada shut the interprovincial Chaudière Bridge, which connects Ottawa's Booth Street and Gatineau's Eddy Street just west of downtown Ottawa, just before 9 p.m. Wednesday. The department said engineers found problems with the masonry around the arches of the bridge during a routine inspection. Experts continued to assess the damage Thursday.

The bridge was expected to be closed for at least a few days and possibly much longer.

Public Works spokeswoman France Langlois said the bridge is not about to collapse. The department just needs time to assess how many vehicles it can handle.

Police directed traffic to use the Portage Bridge instead. (Roger Cote/CBC)

In the meantime, it was a slow commute for many who rely on the bridge to get to work.

Ashley Tetrault usually crosses the bridge on the bus each morning, but when she saw the bridge was closed Thursday, she got off near the University of Quebec in the Outaouais and walked instead to her job at the Royal Canadian Mint.

"If I'd stayed on the bus ... it would've have taken me two hours, maybe 2½ hours to get to work," she said.

Alain d'Entremont, a spokesman for the City of Gatineau, said Thursday that police were at the bridge and nearby intersections all night redirecting traffic, and city engineers are looking at ways to change the lights to improve traffic flow.

An upgrade to the Hydro Quebec dam at the bridge has been suspended during the bridge closure, affecting about 40 workers.

The bridge is the oldest in the region, and collapsed once in 1836.

Carleton University engineering professor David Lau said older structures aren't necessarily less safe than newer ones.

"With regular maintenance, with providing the proper attention to them, they are just as good," he said, adding that some bridges in other parts of the world are several hundred years old and still provide reliable service.