"You can't demand a lot from your government but not give the government the resources to finance it," said Leo de Bever, who has been at the helm of the big provincial fund manager since 2008.
De Bever acknowledges the politics of introducing a provincial sales tax would be tricky for the governing Progressive Conservatives.
Indeed, Premier Jim Prentice has said there won't be a sales tax in Alberta.
But it's not a foregone conclusion that there would be widespread opposition to such a move, de Bever told reporters Tuesday.
Many "thoughtful Albertans" actually do "see the dilemma of relying on a very volatile source of revenue," said de Bever, who will depart AIMCo early next year, handing the reins to investment industry veteran Kevin Uebelein.
"At some point, we have to do what every jurisdiction in the developed and even in the non-developed world has concluded: We have to diversify the sources of revenue."
A sales tax makes sense for Alberta because so many workers in the province actually report their income taxes elsewhere, de Bever said. For instance, the province captures no revenues from the many workers from Atlantic Canada who fly in and out of the oilsands epicentre of Fort McMurray, Alta., for stints of a week or two at a time.
De Bever predicted about a year ago that oil would drop to US$70 a barrel, but didn't see the descent happening as rapidly as it did. Prices are off by more than one third since the summer.
Meanwhile, a return to US$100 a barrel oil, even in long run, may be wishful thinking, he said. That means the oilpatch is going to have to adapt to the new reality by lowering its costs.
De Bever said that can be achieved through new technologies, such as ones that help reduce water use or boost the efficiency of upgrading oilsands bitumen into easier-to-refine crude.
"We're one of the highest cost producers in the world and I don't think that can continue," he said.
Once de Bever, 66, leaves AIMCo, he said he wants to work on helping those technologies along.
Many firms are reluctant to spend on technology during good times because they don't need it, as well as during bad times, because they're tightening their belts.
"Well, when is a good time to invest in new technology if you take that view?" he asked.
"If the end-game is to position yourself for a lower oil price, there are two possibilities: either I'm wrong about oil prices and the reduction in costs is going to increase margins or I'm right about oil prices and it's going to allow you to survive. It seems to be there's not much downside to that scenario."
The same goes for spending on much needed infrastructure to serve Alberta's growing population. Now is as good a time as any to invest in roads and bridges, said de Bever.
"The downtime in the industry, when projects are getting cancelled, is the time to take the productive capacity of the construction industry to fix your infrastructure."
AIMCo, with more than $75 billion under management, manages 27 pension, endowment and government funds in Alberta.
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