Documents obtained by Radio-Canada show that the Agence métropolitaine de transport (AMT) is looking at various scenarios for improving transit from downtown Montreal to the West Island -- from adding more bus service to building a light rail transit system.

The report suggests that light rail would better serve long-term transportation demands, but AMT officials wonder if it's worth the added price tag.

Building a light rail transit system from Pointe-Claire alone is the agency’s priciest scenario, estimated to cost more than $2.5 billion.

If the light rail system were to start and end in Dorval, the plan would cost about $2.1 billion.

Quebec's new transport minister, Robert Poeti, has said improving public transit to the West Island is a top priority  and cost is an important consideration.

“For sure we have to look at the price — what is more efficient for everyone to use, and this is what we want to do,” Poeti said.

More buses or commuter trains

The AMT documents show other scenarios being studied -- one as simple as increasing bus service between the West Island and downtown, adding more buses and creating reserved bus lanes.

This plan — the least costly — would total about $390 million.

The AMT is also considering boosting commuter train service on existing rails and adding tracks that would run parallel to them for an estimated cost of $1.1 billion

Botched report: City Hall opposition

The opposition at Montreal City Hall said the AMT's price estimates were botched from the start — only intending to show that buses are the best option.

“The conclusion seems to have been decided at the very beginning — and at the end, the numbers don't add up,” said Richard Bergeron, leader of opposition party, Projet Montréal.

The AMT refused to comment on the estimated figures contained in the documents.

The transit agency plans to recommend either the bus, train or light rail option sometime in June.