Transportation planners are proposing to trim about $650 million from the proposed Columbia River Crossing, including narrowing the new Interstate 5 bridge from 12 lanes to 10.

The refined project — which includes the bridge itself, along with five miles of freeway improvements and a light rail extension to Clark College — would cost between $2.6 and $3.6 billion if it’s accepted by the 10-member Project Sponsors Council. The council is due to meet on Dec. 4.

Already, at least one member of the council has raised serious concerns about eliminating lanes from the bridge connecting Vancouver to Hayden Island.

Vancouver Mayor Royce Pollard said he found it “ridiculous” to save $30 million by reducing the width from 12 lanes to 10. He said the relatively modest savings — less than 1 percent of the total project cost — leaves him unwilling to abandon the project sponsors’ previous consensus to build a 12-lane span.

“I’m going to press very hard on what we all agreed to,” he said. “As far as I’m concerned, that was as good as a handshake.”

Engineers said they believe a 10-lane bridge will continue to fulfill the general purpose of the overall crossing project: To reduce congestion, improve the movement of freight, offer transit alternatives to commuters, beef up earthquake-resistance, and improve safety in the one the most accident-prone stretches of I-5 in the Northwest.

Planners snipped a lane that would have allowed motorists direct access between state Highway 14 and Hayden Island without having to merge into traffic headed elsewhere.

Pollard said the relatively meager savings in cost isn’t worth it.

“I think we need to plan for the future,” he said. “There are people not even born yet who we need to look out for. The (Vancouver) city council was very adamant that they wanted 12 lanes. I probably won’t be here for the final vote. But, until I leave, this is a hill I’m willing to die for.”

Project planners are also proposing a series of cost reductions by eliminating aspects of new interchanges as Marine Drive and Victory Boulevard in Portland; re-using the existing North Portland Harbor bridge; realigning the freeway on a lower profile across Hayden Island; eliminating a 2 1/2-mile-long lane addition north from Highway 14; and eliminating northbound onramps from state Highway 500 to I-5 in Vancouver.

The trims amount to about $355 million on the Oregon side, and $160 million in Washington.