Hasn't Line 5 at the Straits exceeded its projected life?
Line 5 was built in 1953 by the Bechtel Corporation to meet extraordinary design and construction standards, which still meet or exceed today’s standards for new pipeline construction.
Thanks to its original overengineering—plus a robust suite of extra safety measures at the Straits, including regular inspections, 24/7 monitoring, an aggressive and proactive maintenance program, and remotely controlled isolation valves on either shore—the Line 5 Straits of Mackinac crossing remains in excellent condition today.
Pipelines, like all infrastructure, age at different rates due to environment, general use and other factors—and have an indefinite lifespan if they’re monitored and properly maintained. That’s why there is no blanket approach to how we manage and maintain our pipeline infrastructure. As then-U.S. National Transportation Safety Board (NTSB) chairwoman Deborah Hersman told the Senate Commerce Committee in 2013: “If (a pipeline) is adequately maintained and inspected, age is not an issue.”
Still, Enbridge is committed to building the Great Lakes Tunnel, a $500-million private investment in Michigan, to house Line 5 as much as 100 feet below the lakebed—virtually eliminating the chance of a pipeline incident in the Straits.