Hoped-for increases in Trans-Link ridership may be just wishful thinking, says a report pertaining to a crucial vote today on a $1.24-billion transportation plan.

Transportation commissioner Martin Crilly, who was appointed by the mayors' council in 2009, says growth projections for ridership on the proposed Evergreen Line may not be based on "logic."

"The single largest risk with Evergreen is the forecast of new ridership," says Crilly in a 45-page report released Sept. 30.

"The commissioner is of the opinion that the estimates of 'new' riders appear somewhat optimistic," says Crilly, who has a master's degree in transportation from the University of B.C.

"Hoped-for increases in ridership [on transit as a whole] are not necessarily based on solid grounds," he says.

Crilly's comments came on the eve of an important vote on Trans-Link's proposed spending plan over the next 10 years.

The funding portion, which calls for a two-cents-a-litre hike to the gas tax and a limited-time average $23-property-tax hike in 2013-14, is subject to a vote today at the council of 22 Metro Vancouver mayors.

Mayors told The Province earlier this week that they have enough votes to keep building transit in the region with more rapid transit, buses and roads.

They say they have the necessary votes at today's meeting to approve the first phase of expansion.

Evergreen, a proposed 11-kilometre SkyTrain extension to northeast Coquitlam, is the showpiece.

Its budget is based on ridership estimates. TransLink claims that ridership on the Evergreen and Millennium lines would increase up to 70 per cent from 2014 to 2020.

But Crilly casts doubts on the reliability of those numbers.

He says he has been unable to determine the "robustness" of the estimates and notes TransLink's "data" was lacking on how the projections were achieved.

His skepticism is based on the fact that Evergreen would be built in the "relatively low-density" Tri-Cities area.

As a result, Crilly says, revenues from fares could be short as much as $28 million if ridership falls 25 per cent below expectations.

kspencer@theprovince.com

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