11/22/2013 12:24 EST | Updated 01/25/2014 04:01 EST

A 2nd southbound lane on Champlain Bridge closed Friday morning

Transport officials say they are forced to close another lane of the Champlain Bridge, after the 2-millimetre crack they recently discovered in one of the span’s girders continues to deteriorate.

“Since closing a lane on the Champlain Bridge, we’ve been closely monitoring the girder that requires reinforcement, and in recent days have noted that its condition has continued to decline,” said a statement issued late Thursday night by the Jacques Carter and Champlain Bridges Corporation.

“As a preventive measure, we are obliged to close a second southbound lane to carry out a special inspection to thoroughly analyze the situation.”

Friday morning, two of the three lanes heading towards the South Shore will be closed.

Montreal-bound traffic is not affected.

The corporation urges motorists heading off-island to use either the Mercier or Jacques Cartier bridges, or the Lafontaine tunnel.

Officials will hold a news conference on Friday to provide an update, and inform people of traffic-calming measures until the lanes on the Champlain Bridge are reopened.