Michigan Gov. Gretchen Whitmer has not ruled out construction of an underground pipeline carrying oil and natural gas liquids beneath the Straits of Mackinac. She’s talking with Enbridge, the Canadian energy company that owns and operates an existing pipeline on the floor of the straits.
If those talks fail, the state’s attorney general says she’ll take legal action to shut down Line 5 as soon as possible. Dana Nessel has already issued a legally-binding opinion that effectively halted the state’s involvement in the proposed tunnel project. She says the Legislature acted illegally when it created a new state authority to oversee construction of the tunnel in 2018. After that, the governor directed state agencies to cease any work related to the tunnel.
Nick Schroeck is an associate professor and director of clinical programs at the University of Detroit Mercy School of Law. He says Nessel may argue that Enbridge is in violation of an easement agreement that allowed contractors to build the underwater section of Line 5 in the 1950s.
“Arguably, Enbridge has been violating that easement by failing to maintain support structures and some of the infrastructure that secures that pipeline to the bottom of the lake,” Schroeck says.
Enbridge says Line 5 is supported by 128 anchors spaced no more than 75 feet apart, whereas federal regulations allow spacing up to 140 feet. The company also says it pressure tested the line in 2017, and monitors Line 5 around the clock.
Enbridge says it would take two years to bore a tunnel through the bedrock underneath the straits. It also says the concrete conduit would eliminate the risk of anchor striking the pipeline. In April 2018, an anchor from a passing ship dented Line 5, but did not rupture it.
Environmental groups want Line 5 shut down permanently, saying any leak of oil or natural gas liquids would harm the Great Lakes.
Click on the audio player to hear the conversation with WDET’s Pat Batcheller.
Enbridge’s Line 5 page explaining the tunnel project [with video]