CALGARY, Alberta – TransCanada Corp plans to build a $140 million link to its proposed Keystone XL oil pipeline from the Bakken oil region in the northern United States, a project that would send more crude to a huge Oklahoma storage hub, the company said on Thursday. TransCanada, whose $7 billion XL pipeline to the U.S. Gulf Coast from Alberta is awaiting U.S. State Department approval, said shippers from the fast-developing Bakken oil region have committed to capacity of 65,000 barrels a day on the planned link. That is less than the 100,000 bpd the company had on offer, but pushes the project above its economic hurdle, TransCanada Chief Executive Russ Girling said. "There was substantially more interest in the proposal and as that production comes on, I would expect we would move closer to that 100,000 barrels a day," Girling said in an interview. The line would provide access from Baker, Montana, to Cushing, Oklahoma, the delivery point for New York Mercantile Exchange West Texas Intermediate oil futures, and on to the U.S. Gulf Coast. The Bakken geological formation, straddling North Dakota, Montana and Saskatchewan, is the target of brisk investment as companies employ the horizontal drilling and multistage rock fracturing technology developed for shale gas. Output from the U.S. portion of the region is expected to climb as much as 300,000 bpd by 2015, nearly doubling current overall North Dakota oil output. Pipeline capacity has lagged production increases. The line would start up in the first quarter of 2013, but it is dependent on Keystone XL being approved, TransCanada said. That project, which would move 510,000 barrels a day, faces opposition from environmental groups. They say Keystone XL will bring new oil spill risks to numerous states and drive more Canadian oil sands development. Girling said he still expects a State Department decision by the middle of this year, a time frame that was extended last year, and believes the project's potential economic benefits, including jobs creation and energy security, will sway regulators in favor. Meanwhile, commercial shipments on the final leg of the initial Keystone oil pipeline, which runs to Cushing from Steel City, Nebraska, should start in late February or in March, he said. Rising volumes of Canadian crude imports have already contributed to brimming storage tanks at the hub, which analysts have said is a factor behind a widening spread between U.S. benchmark oil prices and Brent, the world marker. With XL, the link to the U.S. Gulf Coast refining region will counteract further gluts there, Girling said. "Our project is intended to be in service by 2013, which would include the extension of the Keystone XL pipeline from Cushing to Port Arthur, Texas," he said. "If it wasn't cleared by that point, certainly our project would help in alleviating that bottleneck," he said. TransCanada shares fell 23 Canadian cents to C$36.92 on the Toronto Stock Exchange on Thursday.