Enbridge suspended operation of the pipeline in response to bad weather in the Straits of Mackinac. An agreement between the company and the State of Michigan requires the pipeline to be shut down in dangerous conditions.
The 27 November agreement says that Line 5, which runs under the straits, must discontinue operations during ‘sustained adverse weather conditions’, in which “median wave heights in the Straits of Mackinac over a continuous 60-minute period are greater than 8 feet”. The condition sets National Oceanic and Atmospheric Administration measurements as the standard used.
With the increasingly intense public criticism of pipeline leaks, policies like this are designed to mitigate the risk of a catastrophic failure in pipeline safety as well as maintain an optimal social licence to operate.
Enbridge has previously come under scrutiny for failing to disclose wear-an-tear on the aging pipeline, which was originally laid in 1953. According to a statement in October by the Michigan Department of Environmental Quality: “Enbridge Energy Partners, which owns and operates the line, possessed information about the damage [in the protective coating of Line 5] in 2014 and failed to disclose it to state agencies”.
A report from the University of Michigan simulated a worst-case-scenario: the oil leaks to both Lake Michigan and Huron and by the time 90% of the oil has beached after almost 30 days, it will have impacted 168km of shoreline. In a statement, Michigan Governor Rick Snyder said: “Business as usual by Enbridge is not acceptable and we are going to ensure the highest level of environmental safety standards are implemented to protect one of Michigan’s most valuable natural resources”.
The agreement mandates a number of joint assessments of the pipeline, as well as a report on an alternative to replace Line 5 by July 2018. “The purpose of the State’s agreement with Enbridge was to find practical solutions to concerns we had about the operation of Line 5 and the safety of the Great Lakes,” said Valerie Brader, executive director of the Michigan Agency for Energy.
In a cover letter to the signed agreement, a company spokesperson said that the plan will “improve coordination between Enbridge and the State” and provide greater transparency to citizens.