TRAVERSE CITY (AP) — Democratic presidential hopeful Jay Inslee waded into a Great Lakes regional controversy on Wednesday, calling for the defeat of a plan to construct a disputed oil pipeline tunnel beneath a channel that connects two of the lakes.

In a statement released to The Associated Press, the Washington state governor described Enbridge Inc.’s Line 5 pipeline and the proposed replacement tunnel in Michigan’s Straits of Mackinac as “a clear and present threat to the health of the Great Lakes and to our climate.”

“They threaten the clean drinking water that millions depend upon,” Inslee said. “And they would lock in decades of climate pollution that we can’t afford. … This dangerous pipeline must be decommissioned, the proposed oil tunnel must not be built and clean alternatives must be explored immediately.”

Inslee has made addressing climate change the centerpiece of his campaign, which has struggled to gain traction in the crowded Democratic field. He sought to set himself apart by taking a stand on a high-priority issue for environmentalists in the Great Lakes region — particularly Michigan — ahead of debates scheduled for July 30-31 in Detroit.

Line 5 runs for 645 miles (1,038 kilometers) between Superior, Wisconsin, and Sarnia, Ontario, and carries crude oil and natural gas liquids used to make propane. A more than 4-mile (6.4-kilometer) segment is divided into dual pipes that extend across the bed of the straits linking lakes Huron and Michigan.

Enbridge says the pipeline is in sound condition, but it reached a deal last year with Michigan’s then-Republican governor, Rick Snyder, to decommission the underwater pipes and replace them with a new one that would be housed in a tunnel built in bedrock beneath the straits.