Drivers in Metro Vancouver can expect delays and drastic traffic pattern changes as the $3.3-billion Port Mann Bridge construction continues in phases, officials announced Wednesday.

Eight lanes of the new 10-lane Port Mann Bridge will open in December, but starting this month drivers will have access to three lanes as crews complete connections between the bridge and the Cape Horn Interchange.

“It’s all going to come together very quickly over the coming weeks,” said project head Mike Proudfoot, CEO of the Transportation Investment Corporation.

“A lot of work remains to be done between now and when the bridge opens.”

Starting Sept. 16 eastbound traffic on the Lougheed Highway will be moved to its permanent route south of Highway 1.

Two days later, three Highway 1 eastbound lanes will be routed onto the new Port Mann Bridge. On Sept. 19, a new overpass connecting westbound bridge traffic to eastbound lanes on the Lougheed Highway will be opened.

A new overpass will be completed on Sept. 23 and opened over the weekend, connecting the Lougheed Highway westbound to Highway 1 eastbound.

The changes are expected to cause a great deal of frustration for drivers, but Proudfoot said the end result will be worth it.

“When these changes are implemented and the bridge opens in December, drivers can expect a dramatic cut in their travel times,” he said.

“In the meantime we’re asking drivers to please use caution, slow down and watch for signs.”

Proudfoot asked drivers to avoid the Cape Horn interchange and Port Mann Bridge completely during the last two weekends of September, when the bulk of the major work will be done.

When fully operational, drivers will have to pay a toll to use the bridge, but until then motorists will not be charged for crossing.

“There will be specific details on our revised tolling framework announced in the next few weeks,” said Proudfoot.

The bridge is the largest transportation infrastructure project in B.C.’s history according to a release from the TIC.

Construction of the bridge will be completed in 2013, making it the widest vehicle bridge in the world.

The corporation said building the structure while maintaining traffic flow for the more than 100,000 vehicles a day going through the construction zone has been a challenge.

But Proudfoot said the corporation managed to keep traffic moving during construction without any major issues.