In March 2025, Enbridge Inc. announced a major Mainline Capital Investment Program—a $2 billion upgrade to North America’s largest crude oil pipeline network. The Mainline system is the backbone of Canadian oil exports, moving about 3 million barrels per day (bpd) from Edmonton, Alberta, to refineries in eastern Canada and the U.S. Midwest. 
The upgrades are designed to maximize existing steel-in-the-ground, targeting incremental capacity gains and improved utilization, rather than building new Mainline segments. The project will enable up to 150,000 bpd of additional throughput via pump upgrades and flow optimization.
A positive final investment decision was made in November 2025. 
Location on map is not precise. Project cost also represents Flanagan South Pipeline optimization, which connect to Mainline in Illinois.