Even Enbridge acknowledges that Line 5, operating in the Straits of Mackinac since 1953, needs to be replaced. Enbridge wants to build a new Line 5 in a tunnel, advertising that it will make “a safe line safer.” But if a tunnel is bored directly below a pipeline still carrying oil, it makes that pipeline less safe. A poorly designed tunnel increases risk.
Geological engineer and tunnel expert Brian O’Mara said the Enbridge tunnel plan falls far short of industry standards. Instead of taking rock samples every 50-200 feet, Enbridge only sampled every 950 feet. That and other cost-saving design changes pose significant hazards to workers and the environment, according to O’Mara. The V-shaped tunnel design is unusual and suboptimal for boring and safety reasons.
Two preliminary tunnel work accidents have already impacted Line 5: a borehole collapse (9/19) and damage to a remedial support structure by tugs causing the recent shutdown of the east leg.
Delays and cost increases result when tunnel projects encounter problems. But this tunnel risks the Great Lakes. If anything goes wrong during the five to 10 years of construction, a million gallons of oil per hour will be flowing in the degraded pipeline above.
Never has a tunnel been bored directly below an operating pipeline in such a sensitive location. At Sen. Peter’s anchor strike hearing in 2018, Pipeline Hazardous Materials Safety Administrator Skip Elliot called the Mackinac Straits the worst place in the nation for an oil pipeline. Line 5 cannot operate safely while a tunnel is built below it, nor during the years of lawsuits and permitting it will take to decide if a tunnel should be built.
While Enbridge continues to profit, Michigan bears the risk. Michigan only uses about 5 percent of Line 5’s oil today. It cost Enbridge $1.2 billion to clean up 25 miles of the Kalamazoo River when Line 6B ruptured in 2010. Cleaning up 500 miles of Great Lakes shoreline would cost $24 billion at the same rate. Yet, Enbridge refuses to provide the proof of insurance Michigan asked for in July.
Gov. Whitmer promised to shutdown Line 5 first thing if elected. Her U.P. Energy Task Force showed that a prudent decommissioning plan could secure needed propane for the Upper Peninsula to remove the threat of a sudden loss if Line 5 failed.
Owning an oil tunnel for 99 years does not fit the governor’s plan to be carbon neutral by 2050. But a plan is just words unless it is accompanied by action. Protecting the Great Lakes will be Gov. Whitmer’s greatest legacy if she will do it by decommissioning Line 5 — before a tunnel endangers it more.
About the author: Barbara Stamiris, of Traverse City, is a long-time environmental activist. She testified before Congress in 1983 about safety issues at the Midland, Michigan nuclear plant. If the plant opened, it would have been flooded this year during a dam breach. She was named Volunteer Environmentalist of the Year in 2019 by the Northern Michigan Environmental Action Council.