Enbridge in June said it suspected heavy flooding in Alberta may have contributed to the rupture of the 11-mile Line 37 oil pipeline about 44 miles southwest of Fort McMurray.
Parts of Alberta were under a state of emergency because of the flooding. The Calgary headquarters of major oil companies and the Canadian National Energy Board were forced to close down.
About 750 barrels of oil spilled from Line 37. Enbridge said no potable water wells were affected by the release though some of the oil spilled into a small creek and a lake.
The company said it was able to get a section of Line 37 back in service at reduced pressure. Other pipelines in the Alberta region were back on line at full service.
"Enbridge has identified and implemented measures to mitigate ground forces on these lines and will continue such work so as to ensure all pipelines can be operated safely," the company said Thursday.
It said, however, it was unable to determine when all of its Alberta networks will return to full service.