[T]he Alaska Gas Pipeline is the behemoth. Its most likely route would stretch 1,700 miles from Alaska’s Prudhoe Bay to Canada’s Alberta province. The line would cost $20 billion and take a decade to build, but the project has picked up momentum under the whip of Alaska Gov. Frank H. Murkowski (R) and $18 billion in loan guarantees approved last year by Congress.
The second line, the Mackenzie Valley Pipeline, would start 250 miles east of the Alaska line, on Canada’s portion of the Beaufort Sea. It would snake 800 miles through forests of spruce and pine along the Mackenzie River — one of the world’s longest with no bridge or dam. This all-Canada route would cost $6 billion and is predicted to take three years to complete once construction begins.