If Canada's oil production peaks in the next 10 years, it may be difficult for Ottawa to sell the pipeline back to the private sector as Prime Minister Trudeau intended.

Line 3 starts in Alberta and clips a corner of North Dakota before crossing northern Minnesota en route to Enbridge's terminal in Superior, Wisconsin.

Curtailment has done its job to help Alberta oil prices and the latter half of 2020 should see Canada's oil and gas industry improve, according to Deloitte.

Enbridge says an optimization program on its Mainline system — which accounts for about 70 per cent of Canadian oil exports to America — is expected to add 100,000 barrels per day of additional capacity by year-end.

Line 3, which was built in the 1960s and is increasingly subject to corrosion and cracking, runs from Hardisty, Alta. to Enbridge's terminal in Superior, Wisconsin, near Lake Superior.

The court said project's environmental impact statement doesn't address the possibility of an oil spill into the Lake Superior watershed.

Enbridge is working with shippers to optimize its Mainline pipeline system in a bid to boost throughput by 50,000 to 100,000 barrels per day.

With both the Trans Mountain expansion and Keystone XL pipeline projects in court limbo, attention is turning to alternative ideas to expand Canada's ability to continue to get its oil to market.

Besides clearing the legal challenges, Calgary-based Enbridge also needs state and federal permits, which the company hopes to secure around end of the year.

Minnesota Public Radio News reports that it marks the second consecutive year Enbridge has outspent all other lobbyists in the state.