MONTREAL - A huge hole in the Mercier Bridge has been causing massive gridlock and the provincial Transport Minister blames some rapid rot.

"It's a very quick degradation because the last inspection was done in 2008," says Sam Hamad, Transport Minister of the road deck that saw the span sink for several centimeters. An attempt to cover the hole proved inadequate and the hole wreaked havoc on the span Friday, forcing another lane closure. The hole is being repaired overnight Friday and traffic is expected to return to two lanes late Saturday morning.

The hole has combined with other issues on the bridge that include issues with a gusset plate.

Helen Christodoulou, Civil Engineer considers a problem with the steel sheet to be highly unusual.

"If something happened to a gusset suddenly that couldn't be picked up periodically then I'd say it's a serious problem and raises even further questions as to why it has happened," she said.

Motorists had to wait up to four hours to get across the span Friday and many were at their wit's end about their transportation challenges.

One motorist didn't get much reassurance after asking authorities whether the bridge was safe.

"I asked the Transport Quebec if I was safe and even he was even hesitant, so I'm a little nervous," said the driver.

With more than 100 construction projects on the go, not including unannounced 'emergency' closures, the Montreal Metropolitan Community is demanding the formation of an Emergency Committee to co-ordinate projects.

The last straw was this week's closure of the southbound span of the Mercier Bridge, creating a cascade of traffic backlogs and delays kilometres away from the bridge.

Amazingly, the situation went from bad to even worse for drivers wishing to go from Montreal to the South Shore and back.

Friday morning, one of the two lanes remaining on the Mercier Bridge was closed at 7:30 a.m. while repair crews dealt with a problem in the bridge deck.

A section of the decking sunk several centimetres, and while it was re-opened at 10:15 a.m., engineers at Transports Quebec ordered the lane closed again half an hour later.

Early Friday afternoon a temporary patch had been put in place that will be stable enough for the commute home, but bridge officials say they will need to close the lane overnight Friday in order to make a proper repair.

When the permanent patch is finished around 9 a.m. Saturday morning the Mercier Bridge will become one lane in each direction.

While extra trains and buses have been added to ease traffic which was suddenly constrained by this week's emergency closure of the southbound span of the Mercier Bridge, that will not help commuters this weekend.

While all travellers had it bad, those going against the flow were suffering even more. One pair of workers who commute from Lasalle to Chateauguay every morning reported to CTV Montreal that their normal 15 minute drive has turned into a  three-hour ordeal.

Another man interviewed in traffic near the Mercier reported that getting downtown to his doctor's appointment took him two-and-a-half hours while getting back was just as time consuming.

Construction work on Bonaventure and Champlain

Only half of the Champlain Bridge will be open this weekend, with two lanes for traffic heading to Montreal and one lane open toward the South Shore.

Construction crews are replacing the expansion joints on the bridge, in what is the final planned closure for several months.

Those traffic restrictions are in place from 10 p.m. Friday until 5 a.m. Monday.

Meanwhile, the Bonaventure Expressway will be completely closed to traffic from 11 p.m. Friday until 9 a.m. Saturday, and more overnight closures will take place throughout the summer.

On a related note, the closure of the St. Jacques exit on the westbound Ville Marie Expressway has been extended from June 24 until mid-August.

Crews say the construction project was delayed by heavy rain this spring and by the surprise discovery of buried electrical equipment that was not on any blueprint.

Drivers throughout Montreal feeling the domino effect

After quite literally years of reduced traffic flow on the Ville Marie Expressway and the Turcot Interchange because the structure is in such poor shape, removing half a bridge from the already reduced options available to drivers has caused a serious cascading effect on highways kilometres away from the Mercier Bridge.

It's particularly noticeable on the southbound Decarie Expressway where drivers have become used to squeezing into one lane as they go through the Turcot Interchange.

Last weekend the spot where that forced merger takes place was moved further north, and with the Champlain Bridge suddenly becoming the western-most access point to the South Shore each morning, traffic jams got much longer.

A similar problem is happening on Highway 20 Eastbound, since drivers who used to veer off toward the Mercier Bridge now have no choice but to stay on the 20 until they can switch to the Champlain Bridge.

AMT president Joel Gauthier says West Island commuters may get extra trains to bring them downtown, but nothing is certain.

"Everything is on the table. We're looking at it on a daily basis," said Gauthier. 

Lack of co-ordination has mayors steaming mad

The mayor of Chateauguay, frustrated by the ongoing construction delays on bridges, contacted the Ministry of Transportation to voice her displeasure.

"She would like to meet with us," said Transport Minister Sam Hamad. "We will have a meeting as soon as possible."

Her fellow mayors are demanding the creation of an Emergency Committee to oversee and co-ordinate construction projects.

Montreal alone has 60 projects underway to replace long-neglected water and sewer systems. That does not include work being done by other utilities.

"The city is not alone. Hydro Quebec, Transports Quebec, Gaz Metro, we have many other partners that have to work on the city," said City of Montreal spokesman Andre Lazure.

On top of the construction on city streets there are 53 work sites managed by Transports Quebec.