On Tuesday in Kamloops, Dix said he was unlikely to support the expansion if he wins the upcoming May 14 provincial election.
"I don't think that the port of... the Port of Metro Vancouver, as busy a port as it is and successful a port as it is, should become a major oil export port," he said.
In the past, Dix has said he would take a "principled position" and wait for the outcome of the federal review before deciding if he would support the expansion of the crude oil pipeline
The Trans Mountain Pipeline carries crude oil from Alberta to Burnaby, B.C., where it is loaded onto tankers. Kinder Morgan has proposed spending $5 billion to nearly triple its capacity, but the project has yet to undergo a federal review.
The "Kinder Morgan Surprise"
The new position was pounced on by the B.C. Liberals who labeled it the "Kinder Morgan Surprise."
"It's clear that the NDP has no principles whatsoever when it comes to environmental assessment," said Liberal candidate Rich Coleman in a statement on Tuesday.
"I am calling on Adrian Dix to come clean and tell British Columbians when he passed judgment on this proposal. How many times did he and his caucus say they were standing on 'principle' when the very opposite was true?”
Environmentalists also noticed the change in policy, noting the NDP appears to be changing course when it comes to the environment.
It was very different story in the 2009 campaign when NDP Leader Carole James came out swinging against the carbon tax in an effort to capture some of the popular vote.
"Gordon Campbell's gas tax is just going to add pain, and it's the wrong tax at the wrong time," said James at the time.
High-profile environmentalists such as Tzeporah Berman slammed the NDP, with some publicly switching their support to the Liberals.
"At this point, I certainly won't be recommending that if you care about global warming, if you're worried about your kids, that you vote NDP," said Berman, who was the co-founder and campaign director of Forest Ethics at the time.
After Campbell trounced James and the NDP in that election, many suggested the anti-environmental stance may have cost the NDP the election.
Greens are back
This election Dix seems to have learned from that mistake and appears to be taking a greener line on key issues such as pipelines.
Dix has already said he opposes the Northern Gateway pipeline and some green groups appear ready to jump back on board with the NDP.
"I think they took a serious hard look at how to ensure that you're addressing environmental and climate issues and not... playing into it being a jobs versus environmental debate, because it's not," said Berman on Tuesday.
"It may have been in the past but we now have the technologies at scale and the solutions at scale to build a clean economy, and it doesn't have to be an either-or, and I think the new NDP we're seeing is a much greener NDP and a much smarter NDP."
And despite the potential impact on its support, Vancouver Island Green Party candidate Andrew Weaver says they're not worried.
"It was inconsistent, [the NDP's] approach, between Enbridge and Kinder Morgan. But now...we're seeing them actually listen, which is actually showing the importance of electing Green MLAs, because we can raise issues that will never get raised otherwise."
But one candidate who does not see a change is Liberal Leader Christy Clark.
"The problem with the Kinder Morgan Surprise is it's just proof that these are the same old guys, the same old playbook," said Clark
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