The Pollcast: Drilling down on Trans Mountain

Prime Minister Justin Trudeau has pledged that the expansion of the Trans Mountain pipeline, running from the Alberta oilsands to the coast of British Columbia, will get built. The premiers of Alberta and Saskatchewan are threatening retaliatory measures against B.C. if Premier John Horgandoesn't throw in the towel.

Horgan says he won't do that. Instead,on Wednesday he asked the courts to rule on who has jurisdiction over the matter. And for good measure, Quebec hasweighed into the debate, warningthe federal government to tread carefully on matters relating to provincial jurisdiction.

At the heart of the dispute is whether the economic benefits of the pipeline are worth the environmental risks. That's the substance. But it's also about politics.

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There's a lot at stake for Horgan in B.C. He ran on opposition to the pipeline expansion in last year's provincial election and his minority government is only in power thanks to the support of the B.C. Greens, who are adamantly against Trans Mountain.

But the Greens have some political calculations of their own to make. How far can they go in keeping Horganon this track when the party's electoral future depends heavily on the outcome of a referendum on electoral reform scheduled for later this year?

On the latest episode of the Pollcast,Mario Canseco, president of Research Co., joins the podcast to break down the provincial politics behind the Trans Mountain dispute.

Host ric Grenier and Nick Gamache discuss the results of a new survey by the Angus Reid Institutegaugingpublic opinion on the Trans Mountain pipeline and also look ahead to the Liberals' upcoming policy convention in Halifax.

Listen to the full discussion above or subscribe to the CBCPollcast here and listen to past episodes.

Follow ric Grenier, Nick Gamache, and Mario Canseco on Twitter.