The Jacques Cartier and Champlain Bridges Incorporated are requesting commuters from the South Shore use public transit.
The Bridge Corporation and the Agence Métropolitaine de Transport said 7,300 seats have been added on trains, metro and buses to compensate for the lane closed to private vehicles on the Champlain Bridge.
The reserved lane will be extended into the evening in order to facilitate traffic flow, and buses will continue to use the reserved lane on Marc-Cantin Street to access the bridge and avoid traffic on the Bonaventure Expressway.
The bus lanes are part of the Quebec government's plan for 12 short-term measures to help alleviate traffic congestion on the Champlain Bridge while one southbound lane is closed for month-long repairs.
The lane closure comes after workers found a crack in one of the girders supporting the Champlain Bridge.