Enbridge's Earlier Line 5 Tunnel Completion on Offer

Enbridge Inc. (Calgary) said in late 2019 it could have a previously approved but subsequently contested tunnel project built and operational by early 2024, earlier than the more conservative 10-year timeframe that had been expected, the Associated Press reports. The tunnel would run beneath the Straits of Mackinac, a 4-mile-wide waterway that links Great Lakes Huron and Michigan, and would house Enbridge’s Line 5 replacement.

Line 5, a twin pipeline, transports 540,000 bbld of propane and crude oil between Superior, Wis. and Sarnia, Ont. Environmentalists are demanding an immediate shutdown, alleging a failure on the under-water segment could contaminate hundreds of miles of waters and shoreline. That concern comes despite the line’s more than 66 years of operation without incident.

Michigan’s new governor, Democrat Gretchen Whitmer, criticized Line 5 operations during her successful election campaign last fall. The state’s newly elected attorney general, Dana Nessel, was also a critic. Earlier, Whitmer’s predecessor, Republican Rick Snyder, successfully steered a plan through the Michigan Legislature aimed at assuaging environmental concerns. That initiative created a new authority to oversee tunnel construction, with Enbridge describing 2024 as the target date for completion but adding it could take up to a decade.

Following her election, Whitmer ordered a halt to the project and directed Nessel to issue an opinion on its legality. Nessel ruled the Snyder plan violated the state constitution, and thereafter said she would take steps to shut down the underwater pipelines if Whitmer and Enbrige could not agree on a new plan for decommissioning them.

Enbridge issued a statement May 30 regarding the $500-million tunnel project. “In recent meetings and in a letter to the governor, Enbridge has reiterated its shared vision with Michigan of further reducing risk and how we believe constructing a tunnel to house the straits pipelines is the most effective and timely way to remove the existing Line 5 while ensuring the critical energy needs of Michiganders are met,” the company said. The Canadian energy provider added that it had committed to construct the tunnel “as quickly and prudently as possible and to advance a number of additional protective measures while we construct the tunnel. “Given the attorney general’s opinion that the previous administration’s tunnel authority is invalid, Enbridge is engaged and has continued to engage the state about alternatives to address that concern.”

Enbridge outlined that “we can get the tunnel under construction and complete sooner than previously anticipated. Assuming we are able to move through the permitting process without delay, we believe the tunnel can be under construction in 2021 and in service as soon as early 2024.” Operation of the current Line 5 would cease immediately follow- ing placement into service of the new pipeline in the tunnel.

“Line 5 continues to be a critical piece of infrastructure,” the company noted. “It currently serves the propane needs of the Upper Peninsula and northern Michigan, providing roughly 55% of the entire state’s propane needs for heating homes while supporting agriculture and manufacturing needs. Michigan is also a net importer of transportation fuels and Line 5 provides feedstock, not just to the Detroit refinery, but those in neighboring states that are critical to meeting the state’s energy needs. These same refineries supply a large proportion of the aviation fuel at the Detroit Metropolitan Airport, a vital contributor to basic transportation and the state’s economy.”

The company highlighted that pipelines are the safest way to transport energy products, and that it would take 2150 tanker trucks—90 leaving the terminal every hour, 24 hours a day—or more than 800 railcars each day, to deliver the same amount of energy now being carried by Line 5.

The concrete-walled tunnel is to be placed about 100 feet below the lakebed, reducing the risk of a spill to zero. Enbridge would pay for the constrution and operation. On background, there has never been a leak at the Straits of Mackinac in nearly seven decades of operation. Further, a 2017 hydro test on the straits pipelines involving Michigan agencies, the Pipeline Hazardous Materials Safety Administration, the Environmental Protection Agency, and the U.S. Coast Guard validated the lines’ continuing fitness.

(SOURCE: The Weekly Propane Newsletter, June 10, 2019)