The rest of the bridge (902 metres, 986 yards) is owned by the Quebec Ministry of Transport, which is also responsible for the day-to-day operations of the complex, including the federal part.

There is a narrow sidewalk on the side headed to Châteauguay that was for use by foot or bicycle, but it has not been open since major repairs began in 2009.

During the Oka Crisis in July and August 1990, the bridge was closed to all traffic for over a month by Mohawks who supported their brothers from Kanesatake.

This closure period led to violent tempers and clashes between Mohawks and people from Châteauguay, and the extension of Autoroute 30 bypassing the Kahnawake reserve.

As a compensatory measure, the Champlain Bridge Boom was opened to motorists and a temporary rail shuttle was introduced.

During the Caledonia land dispute, certain individuals from Kahnawake erected Warrior and Confederacy flags on the steel trusses of the bridge to show their support.

The bridge was closed for a short period, in order to allow several men from the community to climb the structure and secure the flags.

On June 29, 2007, community members of Kahnawake staged a peaceful protest on the bridge, in support of the AFN's National Day of Action.

The Jacques Cartier and Champlain Bridges Incorporated (JCCBI) (in French: Ponts Jacques Cartier et Champlain Incorporée, PJCCI), a federal Crown corporation, is responsible for managing, operating and maintaining the Mercier Bridge where it crosses the Mohawk Reserve of Kahnawake.

[4] The eight-year work on the federal part, led by contractor, Mohawk Bridge Consortium, was completed by the end of August 2016.

On June 14, 2011, due to the extreme deterioration of 10 gusset plates, the 1930s section of the Mercier bridge was closed until September 6 (in time for school restart).

In 2014, an in-depth study was commissioned to a consortium of BPR, Genivar and SNC-Lavalin firms to determine the optimal solution for the future of the section.