Canadian shipments of crude by rail are poised to surge next year, spurring investment in new export infrastructure.

Crude-by-rail capacity in Alberta is expected to grow by 100,000 barrels a day in December after the provincial government eased production limits for oil transported by train, the Energy Ministry said Wednesday. Western Canadian rail loadings had already climbed as high as 411,000 barrels a day in November despite a week-long Canadian National Railway Co. worker strike that disrupted shipments. Now they’re set to reach 550,000 barrels a day, Alberta Premier Jason Kenney said earlier this month.

Calgary-based Gibson Energy Inc. became the latest company to announce new rail projects in response to the rising demand. The company on Wednesday said it plans to build a million barrels of new storage tanks at its Hardisty, Alberta, terminal, where it also plans to construct and operate a diluent recovery unit that will allow it to send more oil-sands crude by train. SunCoke Energy Inc. and Summit Terminaling are developing a rail terminal to deliver Canadian heavy crude to Louisiana refineries.

Rail has became critical to oil exporters after pipelines filled to capacity two years ago, causing prices to collapse and prompting Alberta’s government to impose limits on some oil production at the start of the year. With no new pipelines scheduled to be built before late next year and projects such as the Trans Mountain pipeline expansion facing legal challenges, exports by train have picked up.

Alberta has eased production limits, causing heavy Canadian crude’s discount to the U.S. benchmark to widen to more than $20 a barrel this month. At that level, crude-by-rail shipments become more economic, encouraging more cargoes, according to John Zahary, chief executive officer of Altex Energy Ltd, a crude-by-rail terminal operator.

“I think probably the next few months will get busier as we get into next year and these movements increase,” he said.