This story was corrected on Oct. 8, 2009. An explanation of the correction is at the end of the story.

Montgomery County Councilmembers shared more doubt than enthusiasm during a committee work session on the controversial plan to turn the Shady Grove Life Sciences Center into a live-work bioscience "urban village."

The 30-plus-year plan to triple commercial space, jobs and housing in a 900-acre area in and around the Shady Grove Life Sciences Center has rallied the county's business and biotech community — and riled neighbors in Gaithersburg, North Potomac and Rockville leery of the impact of the 20 million square feet of commercial space that would be allowed. County planners expect development is more likely to total 15 million square feet, 7 million of which is already built.

The County Planning Board's draft of Gaithersburg West was met with skepticism Thursday at the council's Planning, Housing and Economic Development committee, which questioned the traffic impacts of so much growth in an area already plagued by too many vehicles.

Councilman Marc Elrich blasted the purported parallels to other walkable, transit-oriented communities.

"This is really an inward-facing development and people on the inside aren't going to be walking out," he said. "So this kind of romanticized connectivity that's been put up around this project I think is, fairly, more romantic than real."

Council President Philip M. Andrews added another dozen questions on a range of transportation and transit problems — including planners' statements that 30 percent of all trips through the area will come by foot, bicycle, car pool or mass transit; the impact of five elevated highway interchanges that would have to be built in Science City; and the ratio of jobs to housing.

Looking at a two-mile radius that includes established neighborhoods in Gaithersburg and North Potomac, the area has a jobs-to-housing ratio of 2.8. Gaithersburg West would add 40,000 jobs and 6,000 residences. The county considers 1.6 to be in balance.

"Not in any reasonable sense is it a live-work community. It's being treated as if it can handle the capacity of a metro area when it assuredly can't," said Andrews (D-Dist. 3) of Gaithersburg. "... It's an extremely unbalanced plan that would, by any stretch I can see, significantly worsen traffic in an area where traffic is the major problem, not a lack of job capacity."

Because planners want to revisit Gaithersburg West in six years — rather than the usual 15 or 20 — Elrich (D-At large) of Takoma Park said he is more inclined to approve less density now and let future councils add to it if necessary.

"I don't have to remind this council how difficult it is to take away density once given — that the expectations created around the zoning that will put there may be incredibly difficult to bring back six to 10 years from now should the money or the plans not materialize as planned," he said.

But planning board Chairman Royce Hanson advised against that.

"If you think you're having fun now, think about coming back in a few years and adding a substantial amount of density because there is new demand for it but you have not provided for the infrastructure necessary to handle it," he said.

The work sessions comes as the state evaluates the proposed realignment of the Corridor Cities Transitway to add three stops in the Life Sciences Center. Planning board members have openly and repeatedly said that the vision for Gaithersburg West cannot happen without re-routing the proposed light rail or rapid bus line.

At issue is whether the realignment will boost ridership enough to make the CCT a viable candidate for federal funding as a light rail project. It meets criteria for federal funding as a rapid-bus line. County officials expect the realignment to add 6,000 daily riders, one mile in length, six minutes in riding time and $30 million in costs.

"We're confident that's going to be a net gain for the CCT, but we're waiting for the state to basically see the same thing they see when they crunch their numbers," said Dan Hardy, the planning board's transportation chief.

The state's analysis is expected to be complete within a few weeks.

Because of the state's CCT analysis, committee chairman Michael J. Knapp will wait until the end of the month to make substantial recommendations on the would-be Science City.

"A lot of the density decisions are kind of irrelevant since this is all predicated on transit," Knapp said Tuesday.

Correction: A previous version of this story incorrectly stated the percentage of trips through the area by foot, bicycle, car pool or mass transit. The correct percentage is 30 percent.