Twenty-eight Quebec bridges will be demolished and as many will undergo extensive repairs, said the Quebec's transport ministry, after it finished an extensive review of road structures across the province.

About 135 structures were inspected in recent months after being identified for potential safety risks last summer, following the 2006 Concorde overpass collapse in Laval that killed five people.

The transport ministry will destroy 28 bridges and overpasses, conduct extensive repairs on 25 more structures, and reinforce four bridges from the list of 135 drawn up last summer.

Four other bridges have already been closed because of structural weaknesses.

Officials said 25 of the 28 bridges on the demolition list will eventually be rebuilt.

Transport Minister Julie Boulet said the prognosis comes as no surprise given the gradual decline of Quebec's roads and bridges over the years.

"We've known for many years that the road network, that its bridges and overpasses, are aging, and that many of them need action," she told CBC's French-language service.

The provincial commission created to investigate the Sept. 2006 Concorde overpass collapse recommended midway through its public hearings last year that further inspections be conducted immediately on bridges and structures built on a similar model.

Commission president Pierre-Marc Johnson said he's not surprised so many structures are now red-flagged, given the problems his investigators found while testing similar rebar-reinforced bridge models in the laboratory.

Transport Quebec's verdict following inspections will send a positive message to Quebecers, he told CBC Montreal. "I think it's reassuring for public opinion, to see that what had to be done was done, and the bridges at risk are identified and will be taken care of."

Five people died in the Sept. 2006 collapse on Highway 19, north of Montreal, sparking a firestorm of questions about Quebec road safety.

In his final report, released in October 2007, Johnson concluded a confluence of factors contributed to the Concorde overpass failure, including design and material flaws, and inadequate road construction codes.

The commission's report made 17 recommendations to improve road safety, including stable infrastructure funding and an independent bridge agency.

Johnson reiterated Wednesday that the province should seriously consider creating an independent body to oversee the renewal of road infrastructure, which will cost the province billions of dollars in the next decade.

"We need very specialized operations, you need a major task force-like approach to deploy this huge infrastructure capital in the province," said the former Parti Québécois premier, who now works as a lawyer for Montreal firm Heenan Blaikie.

"I think it would be useful to have an agency to do that, rather than a department."

Some bridges and overpasses scheduled for demolition, with start date:

• Monette Street overpass, Route 138 (for Mercier bridge), Montreal (2009 or 2013).
• 520 West service road overpass, Highway 520, Montreal (2008).
• Autoroute 19 overpass, Gouin Boulevard, Montreal (2009).
• Gorman Bridge, Highway 309 in L'Ange Gardien, Gatineau (2008).
• Gauvreau Bridge, Highway 366 in La Pêche, Gatineau (2008).
• Autoroute 10 overpass, Route 112, Magog (2008).
• CP Rail overpass, Route 112, Eastern Townships (2008).
• Rivière Dagenais Bridge, Route 101, Abitibi (2008).
• Ruisseau Alain Bridge, Route 132, Gaspésie (2008).
• Ruisseau Marie-Anne Bridge, Route 224, Saint-Hyacinthe (2008).
• Lac Fraser Bridge, Route 220, Orford (2008).
• Ruisseau St-Camille Bridge, Route 216, Saint-Camille (2008).
• Rivière St-Francois Bridge, Route 161, Weedon (2008).

Some bridges and overpasses scheduled for major repairs, with start date:

• Autoroute 720 overpass, Bleury St., Montreal (2008).
• Autoroute 13 overpass, Cote-Vertu Blvd, Montreal (2008).
• Rue Labelle Overpass, Highway 40, Quebec City (work in progress).
• Ruisseau Gear Bridge, Route 104, Cowansville (2008).