CALGARY - Enbridge Inc. faces a growing public relations nightmare around an oil spill in a Michigan river amid reports the pipeline company knew of corrosion on the ruptured line weeks before the incident.

The Calgary-based company, under fire for a 3.3 million litre crude oil spill into the lush Kalamazoo River, admitted Thursday the aging Line 6B had been subject to more than 100 repairs during the past year.

But the ruptured pipe near the town of Marshall had not been tagged as a hot spot in Enbridge's maintenance plan.