Another proposed crude oil pipeline, along with another round of controversy, is coming to northern Minnesota.

Pipeline operator Enbridge Energy on Friday asked state regulators for approval to build a $2.1 ­billion, 337-mile pipeline to replace a 1960s-era Line 3 pipeline. It carries crude oil from Canada to the Midwest, but has a history of ruptures.

The Minnesota segment is part of a $7.5 billion project by the Calgary-based company to build a new 36-inch diameter line from Hardisty, Alberta, to Superior, Wis., where Enbridge has a terminal and connections to pipelines serving the Midwest, Gulf Coast and eastern Canada.

Like Enbridge’s other big Minnesota pipeline project — the proposed Sandpiper from North Dakota — the Line 3 replacement would pass through Clearbrook, Minn., site of two oil terminals, then turn southeast toward Park Rapids, and finally east to Superior.

Although the two lines are on the same route, Enbridge is required to get a separate route permit for Line 3, along with a certificate of need. ­Earlier this month, an administrative judge concluded that the Sandpiper project is needed. Now that same kind of review — with hearings across the state and reams of written filings — starts for Line 3. The process will take months.

In lengthy filings with the state Public Utilities Commission, Enbridge said that growth in western Canada’s crude oil production over the next 15 years will quickly fill the new, expanded Line 3. The company wants to begin construction next year, and finish in 2017.

An analysis for Enbridge by consulting firm Muse Stancil said that Canada’s National Energy Board projects a 2.1 million barrel per day increase in production from Alberta’s oil sands by 2030. Enbridge’s Line 3 replacement would carry 760,000 barrels per day.

“The forward outlook for western Canada is one of very large increases in crude oil supply,” Muse Stancil concluded. “The project represents a small portion of the transportation capacity that will have to be utilized over the next decade.”

Oil shipped via the expanded Line 3 will reduce restricted deliveries caused by pipeline bottlenecks that affect two refineries in the Twin ­Cities and others in the Midwest, Gulf Coast and eastern Canada, Enbridge said.

The existing Line 3 pipeline, which takes a different path past Bemidji, Grand Rapids and Cloquet, would be decommissioned. Enbridge said that line operates at partial capacity and has “a large number of integrity anomalies.”

Accidents on the existing Line 3 have included a record 1991 spill of 1.7 million gallons of crude oil at Grand Rapids, a 2002 rupture near Cohasset and an explosion and fire during a 2007 repair job near Clearbrook that killed two workers.

Phillip Wallace, a Pipeliners Union business representative for welders in 42 states, including Minnesota, said the project likely will mean 800 to 1,000 jobs for a range of trades.

MN350, an environmental group focused on addressing climate change by reducing fossil fuels, plans to fight the project, said Andy Pearson, the group’s Midwest Tar Sands coordinator. “If Line 3 is a hazard, they need to be shutting it down,” he said in an interview. “We believe they shouldn’t rebuild it … MN350 opposes expanding tar sands through Minnesota.”

The timing of public meetings for Line 3 has not been set, nor have the dates been announced for a final round of Sandpiper hearings.