MONTREAL - The Mercier Bridge is undergoing construction this weekend, and because of winter weather, traffic will be limited to one direction at a time.

In December the Bridge Corporation had to close the western span, but strong winds threatened to move pylons placed in the centre of the bridge to separate traffic.

As a result the group overseeing construction came up with a plan that will see traffic flow alternate, with cars being able to come into Montreal for part of the day, and go to the South Shore at other times.

The traffic flow changes kick off at 10 a.m. Friday and will continue until 5 a.m. Monday.

Traffic on the Mercier

Friday, Jan. 27, 10 a.m.: Two lanes open Southbound. No traffic to Montreal.

Saturday, Jan. 28, 5 a.m.: Two lanes open toward Montreal. No traffic to the South Shore.

Saturday, Jan. 28, 3 p.m: Two lanes open Southbound, No traffic to Montreal.

Sunday, Jan. 29, 5 a.m.: Two lanes open toward Montreal. No traffic to the South Shore.

Sunday, Jan. 29, 3 p.m.: Two lanes open to South Shore. No traffic to Montreal.

The construction should wrap up by 5 a.m. Monday, at which point two lanes will be opened in each direction.

Jacques Cartier Construction

The underside of the Jacques Cartier Bridge will also undergo repair this weekend.

As a result traffic will be limited, but not eliminated, over the next few days.

Between 10 p.m. Friday and 5 a.m. Saturday, only one lane will be open in each direction.

From 5 a.m. Saturday until midnight Sunday drivers can use two lanes each way.

From midnight Sunday until 5 a.m. Monday only one lane will be open each way, and again from 9 p.m. Monday until 5 a.m. Tuesday.

Drivers worried about traffic delays should take the Champlain Bridge or the Lafontaine Tunnel.