MONTREAL - After ferrying millions over the raging St. Lawrence for five decades, the aged and creaky Champlain Bridge's days are numbered.

The span, Canada's busiest, is to be replaced by the federal government within 10 years at the cost of about $5-billion.

But the shape and design of the new bridge remains unknown, so 200 people met Saturday to discuss their ideas for the upcoming crossing.

The meeting was organized by Hoang Mai, NDP MP for Brossard-Laprairie.

"The idea is to get the people together, to know the concerns, the objectives, the idea of what they want, the ideas behind the new bridge would be," said Mai.

Some mulled over whether the bridge should contain a toll charge while others lobbied for the concept of making a bridge that could carry more vehicles.

Thus far the federal authorities have yet to announce any details. It's still not even known whether it will be replaced with another cantilever bridge structure or whether a beam, arch or suspension structure will be built.

Another common thread in the discussions was the construction technique: many insisted that it be built in a sturdy way so as to not require another rebuild in five decades.

The Champlain Bridge was approved by Prime Minister Louis St. Laurent and built between 1955 and 1962 at the cost of $35-million, which was funded by a 25 cent toll that was eventually abolished in 1990.

The new bridge will be the lynchpin in the local river crossing network and its functionality has to meet high expectations, as experts noted Saturday.

"A bridge which takes a third of the traffic crossing to Montreal is a key element to Montreal's economy, which in itself is a key element to Canada's economy," said Urban Economist Richard Shearmur.

The NDP has bemoaned the fact that the feds have yet to even offer the slightest sniff of what's in their plans for the new bridge.

"Currently we're in the dark about everything," said Deputy Transport Critic Jamie Nicholls. "We need a plan to be communicated to the people so it doesn't raise a thousand questions."

Either by coincidence or design, the federal transport minister Denis Lebel issued a press release Saturday promising to issue more information Sunday on the state of the new bridge.