Green Party Leader Andrew Weaver is calling for a provincial inquiry into the Port Mann Bridge project after a year long CBC News investigation raised questions about the project's oversight.

"I was profoundly troubled ... we are not talking about a few tens of thousands of dollars, we are talking about hundreds of millions of dollars ... accounted for in ways that seem very odd," said Weaver.

Documents leaked to CBC and six sources close to the project say the B.C. government overpaid millions to speed up work on the Port Mann Bridge project in 2012.

Weaver is calling on the NDP government to launch an inquiry that would review the entire project, including why the province spent millions extra to speed up the work.

"We need to ask very difficult questions as to why was this project apparently accelerated to complete prior to the provincial election," said Weaver.

Six consultants on the project told CBC they believe weak oversight led to $300 million spent on acceleration but TI Corp, the crown corporation created to build the bridge and widen the highway, says in the end they got $200 million back after negotiations with the contractor.

NDP not ruling out inquiry

The new B.C. NDP government say it is reviewing the information uncovered by CBC's investigation before making a decision on a public inquiry.

"We need to take a look and make sure this never happens again," said Municipal Affairs and Housing Minister Selina Robinsion.

She said her government is concerned taxpayers' money may have been used to help get the B.C liberals elected in 2013.

'Very concerning if tax dollars were used for the sake of the BC Liberals partisan interests,' said Municipal Affairs Minister Selina Robinson.

"I'm outraged on behalf of all British Columbians that tax dollars would be used to potentially speed up a project in order to advance a B.C. Liberal agenda for an election."

She said if millions of taxpayers money was wasted to speed up work on the project, serious questions must be answered.

Makes me want to scream - Selina Robinsion , NDP minister of municipal affairs and housing.

"Everything about this is concerning. All the pieces for me make my stomach hurt with outrage because the alleged misuse of tax dollars when we had cuts to education, when we had cuts to senior care, makes me want to scream," said Robinson

B.C. Premier Christy Clark opened the Port Mann Bridge on Dec. 1, 2012 saying the project was 'on budget' but it was actually $572 million over the original fixed price of $2.39 billion. (The Canadian Press)

Former Premier Christy Clark opened the bridge on schedule in December of 2012. Standing on a podium on the old bridge with the new span in the background, she boasted the new Port Mann would shave an hour from drivers' daily commutes.

Documents leaked to CBC suggest part of the project, the Fraser Heights connector, finished early. TI Corp said the Crown corporation did not pay extra to accelerate that work.

Weaver says an inquiry would also uncover why TI Corp was allowed to spend billions without establishing an audit committee until 2013, which is required for all B.C. Crown corporations.

"This is not good fiscal management. It's actually fundamentally irresponsible, and we need to get to the bottom of this with an independent public inquiry," said Weaver who had not yet discussed the matter with Premier John Horgan.

Weaver also questioned why the former B.C. Liberal government only released documents requested by CBC two weeks after the May election, which was seven months after they were requested by CBC

Watchdog questions timing before election

'An independent forensic audit will tell you if you need a public inquiry,' said Dermod Travis, executive director of the watchdog group Integrity B.C. (CBC) (Daniel Beauparlant/CBC) A watchdog group is also concerned politics may have motivated the acceleration of the project, which allowed as many as 100,000 potential voters a day to shave time off their daily commute before the 2013 election.

"It doesn't make sense economically, it only makes sense politically and that is too high a price for all taxpayers to pay for the benefit of the B.C. Liberals," said Integrity B.C.'s Dermod Travis, who has been monitoring B.C.'s megaprojects for years.

The former B.C. Liberal government claimed the whole project came in within its $3.3 billion capital budget, but the project's debt is now projected to hit $4.2 billion this fiscal year, and the bridge is losing $100 milllion a year.

B.C. Liberals deny acceleration

The former transportation minister rejects any criticism that his party rushed work on the bridge for political gain, though he acknowledges the project was built before he was elected.

Todd Stone also said no part of the project was speeded up.

"I have had the understanding all along right to this day that there was no acceleration of this project, that in fact the original completion date for the entire project was to have the project finished by the end of 2012, and that is indeed what happened," said Stone.

B.C Transportation Minister Todd Stone slapped a 'completed' sticker on the project September 17, 2015 at a ceremony with Port Mann Bridge workers and engineers. (CBC)

But the contract schedule said the final stretch of highway, called the Fraser Heights connector, wasn't required to be finished until the end of 2013.

Documents leaked to CBC said that work finished early.

TI Corp confirmed to CBC that it negotiated $300 million in invoices down to just $100 million.

Those same invoices refer to 'acceleration' more than 100 times.

TI Corp also told CBC extra money and resources were applied to ensure the Cape Horn interchange was ready when the bridge opened, but the Crown corporation denied any other work was accelerated.

"There were no concerns expressed to me by ministry staff or TI Corp staff that anything untoward was done here," said Stone.

Read CBC's Port Mann investigation here:

The Port Mann Bridge, seen here mid-construction, before the old Port Mann Bridge was demolished. (Flatiron Construction )

READ: Inside CBC's Port Mann Investigation: How we did it.

If you have information on this or any other story we should investigate, email: Investigate@cbc.ca

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