According to a study published by the University of Michigan, in partnership with the National Oceanic and Atmospheric Administration, a leak in Enbridge 5 near the Straits of Mackinac could affect roughly 700 miles of shoreline. Key areas recognized for the highest potential risk include Mackinac Island, Bois Blanc Island, Mackinaw City, and areas on the northern shore and southern shore of the Straits. The study found that 3,528 square miles (15%) of Lake Michigan's open water and roughly 13,611 square miles (60%) of Lake Huron's open water could be impacted by visible oil. In addition, highly turbulent flowing currents found within the Straits of Mackinac, combined with the degrading enzymes secreted by zebra mussels, and aging pipe welds and coal tar enamel, increases the risk for corrosion and potential fissures to occur in the pipes. Due to these issues, expert reports concluded that Line 5 should be shut down in the Straits pending a full review under state public trust law. Although the U of M study showcased worst case scenarios, experts recommend completing a risk analysis that includes, "1) analysis of environmental impacts, 2) cleanup costs, 3) restoration and remediation measures, 4) a natural resource damage assessment, and 5) Economic damage to public and private sector interests." In late June 2019, the state of Michigan filed a lawsuit asking the Ingham County Court to compel the decommissioning of the segment of Line 5 that runs under the Straits of Mackinac; the dual pipes, in use since 1953, were then shipping 540,000 barrels of oil and propane per day. A Reuters news report defined Line 5 as "a critical part of Enbridge’s Mainline network, which delivers the bulk of Canadian crude exports to the United States". The basis of the suit is the claim that the pipeline is a public nuisance and violates the Michigan Environmental Protection Act since it may become the source of pollution. The news report adds that "it is unclear if Line 5 could operate without the Straits segment". Attorney General Dana Nessel made this comment: "We cannot prevent accidental or emergency anchor deployments in one of the busiest shipping channels in the Great Lakes. And it only takes one such incident to cause an environmental and economic catastrophe. That is a risk no one should be willing to take". Michigan Senate Republicans expressed concern about the potential shutdown of the pipeline. In their view, that move would create other problems, as reported by The Detroit News. "the loss of thousands of construction jobs expected from the tunnel construction, an increase in costs at Detroit and Toledo refineries and the loss of a significant mode of propane transportation in Michigan.