PETOSKEY (AP) — A Canadian-based energy transportation company’s preparation of a proposed tunnel that would house a petroleum pipeline caused a borehole to collapse in Michigan, which left debris in the waterway.

Enbridge Energy had been collecting rock and soil samples, which it finished Sept. 12 the Petosky News-Review reported. But the company did not report the incident to Michigan Department of Environment, Great Lakes and Energy until Nov. 19, according to documents obtained by the newspaper.

The collapse also caused a long piece of drill rod to become lodged beneath the lake bed, and a piece of the equipment to fall on top of the lake bed.

The tunnel would enclose the Straits of Mackinac’s portion of the 66-year-old pipeline, which is also known as Enbridge Line 5. It runs from Superior, Wisconsin to Sarnia, Ontario.

Ryan Duffy, Enbridge spokesman, said the two-months span between the date of the incident and the report were spent determining the best way forward. And now, the company won’t be able to retrieve the debris until at least spring 2020.

“We were evaluating ways to go down and get it, and looking at the best way to go forward,” Duffy said. “We hoped to do it this season … It would be a dive operation that would be high risk in the cold weather, so we’re just going to retrieve it in the spring.”