Most members of a panel of land-use experts concluded last night that widening Route 32 in western Howard would spur development throughout the region.
Their estimates on how much varied from no additional houses to as many as 7,300.
State Highway Administration officials asked the nine-member group to determine the impact improvements to Route 32 would have on Howard, Frederick, Carroll and Montgomery counties.
The highway agency is considering three options for the section between Route 108 and Interstate 70: widening it from two lanes to four lanes and putting in interchanges, adding interchanges only, or leaving the road as it is.
County officials and some residents are worried about safety on the road, which has become more congested with population increases in the region. But some West Friendship residents think widening Route 32 would bring more houses and cars instead of solving the problem.
Most members of the land-use panel said they don't think widening would have a tremendous impact.
With a few exceptions, they predicted that a four-lane Route 32 would bring fewer than 3,500 additional homes to the region in the next 20 years.
"It seems we have relatively good consensus as a group that there's going to be some impact, but it's going to be minor," said Joseph M. Cronyn, a Columbia real estate consultant.
A few members of the panel said the impact of a wider Route 32 might seem huge to residents who end up with several hundred additional neighbors as a result.
"If you're living in that area, these could be significant changes," said Nancy Lefenfeld, a Columbia market analyst.
Planners project 29,500 new houses by 2020 in the vicinity of Route 32 in parts of Howard, Frederick, Carroll and Montgomery counties.
The panel members differed widely in some cases. Dan Pontious, who leads the Baltimore Regional Partnership, forecast 24,400 additional houses if the road isn't changed. Growth-management expert Douglas R. Porter predicted 31,200 additional houses.
Panel members' predictions for development with a four-lane highway ranged from 29,500 additional houses to 34,100.
The estimates for western Howard and nearby parts of the county also varied. Some forecast an additional 8,900 houses by 2020. Others estimated 6,300.
Joseph W. Rutter Jr., Howard County's planning director, said 6,300 houses can be built on the land under current zoning regulations. The county expects all developable land to have been used by 2020.
Some panel members said development pressure can prompt zoning changes.
Panel members agreed that the number of lanes on Route 32 will be one of many factors affecting development decisions.
"There are plenty of pressures out there for land development in the study area," Lefenfeld said. "The road is irrelevant, almost."
Panel members, who met in Columbia last night, said they don't expect to gather again.
Their next step is shaping a report - probably by the end of June - that highway officials will consider when deciding the fate of Route 32.
Noting the lack of consensus on some points, Pontious said he is not sure what state officials will get out of the panel's work.
"I think that's the main question," he said. "I'm unclear how it will be used."
Rutter, who has not supported any of the proposals, said the panel's development predictions told a clear story.
"The margin was so small that that's not what should drive the decision," he said. "They were very close."