TransLink is blowing smoke when it claims a turbocharged transit system will do much to fight climate change or encourage drivers to park their cars.

That's the blunt analysis of Mary Jo Porter, an adviser to the TransLink Commissioner.

Speaking to TransLink mayors Sept. 16, Porter poured cold water on TransLink's key message that an ambitious expansion, at a cost of an extra $450 million a year, is critical to chopping greenhouse gas emissions.

"No matter how much transit system upgrades you put out, people won't stop driving in large numbers unless it works for their lives," she said.

People will commute to work in job-dense employment districts because transit can get them there.

But good luck getting them to use transit to shop on the weekend or take the kids to school or daycare, she warned.

The mayors and TransLink want the province to deliver new funding sources – like road pricing or regional tolling – to finance the $450-million expansion, without which they say they can't afford to build and run the Evergreen Line or other rapid transit expansions in Surrey and Vancouver.

Victoria has so far refused and that unfunded scenario will be off the table Oct. 23 when mayors vote on the new 10-year plan.

Instead, the mayors will choose between a "drastic cuts" base plan that freezes funding at current levels and slashes bus service or a "funding stabilization" option that raises an extra $130 million, mostly from gas tax and fare hikes, to maintain the system as it now exists while longer-term improvements are pursued.

But the commissioner's office has released estimates showing TransLink will remain far short of its target of a one-third cut in greenhouse gas (GHG) emissions – no matter which 10-year plan option is picked.

The findings, independently prepared by outside consultants The Underhill Company, show Metro Vancouver carbon emissions will drop by no more than 6.9 per cent by 2019 under both the drastic cuts plan and the funding stabilization plan.

And that would improve to just a 7.3 per cent GHG reduction under the $450-million deluxe expansion that delivers three new rapid transit lines and seven new bus rapid transit lines.

The reason for the anemic gains is that the total kilometres driven by motorists in the region are projected to keep climbing substantially, no matter the scenario chosen, Porter said.

Virtually all gains on emissions come via cleaner vehicle engines and fuels, not from increased transit attracting more riders.

Her conclusion: a costly mega-expansion of transit that pours billions of dollars into increased service is a "very inefficient and expensive tool" to try to reduce carbon emissions.

Moreover, she said, TransLink doesn't have direct responsibility for achieving climate change targets, it has inadequate tools to do the job and its proposed plans are basically ineffective on that front.

Local cities wield far more influence in shaping growth and reducing car trips through smart growth policies, she said.

That means zoning for higher densities and walkable, livable neighbourhoods, and rejecting new suburban office parks "in the middle of nowhere" that raise transit service costs and hinders efficiency.

"TransLink cannot control this," Porter said of carbon emissions. "The mayors around this table, with a stroke of the pen in their offices, can accomplish more than [TransLink] can with millions of hours of service."

She said TransLink's frequent transit network that guarantees service at least every 15 minutes on a widening grid is a powerful and promising idea, but one whose success depends on civic development policies.

TransLink Commissioner Martin Crilly, who independently advises the mayors on TransLink's plans and assumptions, also argues road pricing measures that boost the cost of driving must accompany expanded transit if ridership is to reach a target of 17 per cent of all trips, up from 11 per cent now.

"We take some exception," TransLink CEO Tom Prendergast said in response to the findings of Porter and the commissioner.

"While we agree we don't have total influence [on GHG cuts and the share of transit trips] – we're not in total control of our destiny – we certainly have partial influence."

He added TransLink has never taken the position that transit alone can dramatically alter people's transportation behaviour and that it must happen in concert with land-use decisions led by cities and Metro Vancouver.

A segment of the population will be attracted by better transit service, Prendergast said, while others will need either positive carrots or negative sticks such as road pricing to prompt change.

Vehicles make up 35 per cent of Metro Vancouver's greenhouse gas emissions.

The top goal of TransLink's 30-year vision, Transport 2040, is to aggressively reduce GHG emissions from transportation. It also sets a target of having most trips in the region taken by transit, walking or cycling.