Opponents of a $102 million ramp project had plenty to say Tuesday night.

Addressing the City Council and an overflow crowd, a half-dozen San Ramon speakers voiced skepticism that the proposed Norris Canyon High Occupancy Vehicle Project would have a significant effect on traffic congestion.

They said it would negatively affect their quality of life by increasing traffic and noise in their neighborhood and reducing safety by increasing numbers of buses and trucks on Norris Canyon Road, where children ride bikes to school.

San Ramon resident Jeff Rackmil said the project plan is "built on a house of cards."

"We know that it will reduce safety, increase noise, increase light from new signage and cause disruption during construction," he said later. "At the end of the day, if you've built it for $100 million and only a few cars are peeled off, is it worth it?"

Susan Miller, director of projects for the Contra Costa Transportation Authority, said after the meeting that the public's feedback will send her team back to the drawing board to reconsider an option for an HOV ramp at nearby Executive Parkway, previously considered a less suitable location.

The Norris Canyon project is being funded by the Contra Costa Transportation Authority with Measure J funds and is part of a regional plan to improve traffic along the Interstate 680 corridor. The project is in the environmental impact report stage, a document that Miller said will cost about $2 million to prepare. The draft report is expected to be done in April 2013.

The proposal calls for on- and offramps on the Norris Canyon Road overpass that would allow direct access to I-680 HOV lanes. The ramps are intended for buses, carpools and vanpools headed to and from San Ramon's employment centers, such as Bishop Ranch Business Park. They are expected to relieve traffic on Bollinger Canyon and Crow Canyon roads.

A second option for the project is for a ramp at nearby Executive Parkway, and a third is to cancel the project altogether.

Two previous public meetings in November and March were attended by neighbors overwhelmingly in opposition to the project.

"What we've been hearing is that people are more receptive to making a connection at Executive Parkway," Miller said.

She said planners thought residents would want ramps that connect the east and west sides of the freeway. A new overpass at Executive Parkway would be difficult and expensive to construct, but Miller said feedback suggests an overpass might not be needed and that residents would be satisfied with ramps that connect only to the east side of the freeway, where Bishop Ranch is located.

A public workshop is planned for the fall, when the option for ramps at Executive Parkway will be presented, Miller said.

The City Council said that studies should continue before any decision is made.

"Let's get it right or get rid of it," Councilman Dave Hudson said.

Contact Jason Sweeney at 925-847-2123.