Rae toured Fort McMurray's oilsands operations by air and land on Tuesday.
"The benefits for the country are tremendous in terms of manufacturing, the number of jobs, the number of contractors across the country, in Ontario and Quebec, who supply the extent of the work that is going on here," he told reporters.
But Rae adds it's essential that the industry be regulated properly by both the federal and Alberta governments.
The Liberal leader says most observers say internationally, Canada lags behind in terms of regulation of the oil and gas industry.
However, Rae says both Alberta and Ottawa are now acknowledging that there's a need to catch up and that governments need to do their jobs as well.
"A development of this size, of these dimensions, obviously requires a healthy oversight. And I think we want to make sure there is in place, stronger reviews with respect to air quality, stronger reviews on water quality."
Rae was asked about an investigation by a U.S. agency into Alberta-based Enbridge Inc.'s handling of its crude pipeline spill in Michigan in 2010.
The U.S. National Transportation Safety Board concluded Enbridge did not fix a defect on the pipeline when it was discovered five years earlier and control room staff responded poorly when Line 6B ruptured on July 25, 2010.
The board said Enbridge staff handled the spill like "Keystone Kops."
"It speaks to the need to make sure we have strong regulation and that the regulation has integrity," Rae said.
Enbridge also has billions in new pipeline projects and expansions in the works, including contentious plans to ship crude to the West Coast and to Central Canada.
There have been protests at hearings about Enbridge's proposed Northern Gateway pipeline between Alberta and the B.C. coast.
Natural Resources Minister Joe Oliver said as the hearings were about to begin earlier this year that "radical'' foreign environmental groups were hoping to bog down the process through the number of presentations made to the public hearings.
Rae said the federal Conservatives' desire for expansion has usurped the need for a real debate on the real risks of oil and gas infrastructure.
"What disturbs me about Mr. (Steven) Harper and his ministers is the speed with which they've attacked those people who've expressed concerns about where pipelines are going, the routes involved and the implications of those routes."
Rae says sustainability — not just of the development, but of communities such as Fort McMurray — and balance are key.
He applauds some oil companies for promising to restore the land back to its original state.
"I think if you look at the commitments that some of the companies are making to environmental reclamation, it's impressive, but everyone has to recognize that that reclamation process of getting that land back to a state close to where it was at the beginning, also requires strong regulation."
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