Enbridge has restarted its Wood Buffalo pipeline between Fort McMurray and Cheecham, shut down as a precaution following a leak of another pipeline that uses the same corridor to transport oilsands production from northern Alberta.

The leak of Line 37 was caused by heavy rainfall, which triggered ground movement on the right-of-way, the company says.

The Wood Buffalo pipeline was restarted at reduced pressure pending completion of further geotechnical analysis in the area where the leak occurred, Enbridge said Tuesday.

The company made an initial estimate of a loss of earnings of $1 million a day because of the shutdowns.

The relatively small leak, estimated at up to 750 barrels, occurred on the pipeline from the Long Lake oilsands project to Enbridge's Cheecham Terminal.

The Wood Buffalo pipeline connects at Cheecham with the Waupisoo Pipeline (Line 18), which runs from Cheecham to Edmonton; the Waupisoo Pipeline was returned to service at normal pressure on June 25.

The 540-kilometre Athabasca line can carry up to 570,000 barrels per day of crude from the Athabasca and Cold Lake regions to Hardisty, Alta., a major pipeline hub in eastern Alberta, about 200 kilometres southeast of Edmonton.

The Waupisoo line can carry up to 600,000 barrels per day to Edmonton from Cheecham Terminal, near the site of the spill, about 70 kilometres southeast of Fort McMurray, Alta.