In this July 29, 2010, file photo, a worker watches water come out of a pipe in Talmadge Creek where booms have been set up to contain an oil spill in Marshall Township, Mich., near the Kalamazoo River.
Enbridge Inc. said on Friday that it returned its 491,000 barrel-a-day (BPD) Line 5 oil pipeline to service after repairing a leak in Michigan.
"We will have an update on Line 1 later today," company spokeswoman Lorraine Little said in an e-mail.
The company had shut Line 5, which is running from Superior in Wisconsin to Sarnia in Ontario, on Thursday to repair a small leak, estimated to have been less than three barrels at a site in Arenac County, Mich.
Enbridge also shut Line 1, a 237,000 BPD line that extends to Superior from Edmonton, due to high inventories at the end of that segment and lowered pressure on Line 5 to investigate other possible trouble spots of the leak.
"The temporary incremental pressure restriction is on Line 5 and will last until a review of similar features from inspection tool runs has been conducted," Ms. Little said.
The company's pipelines carry the bulk of Canada's crude exports to the United States.