Developers and economic development officials in suburban Maryland say the 18-mile intercounty connector highway that would stretch from Gaithersburg to Laurel is likely to speed several commercial projects planned along the corridor, intensify growth in underdeveloped areas and spur new growth farther out.

The announcement by Maryland officials on Monday that they plan to proceed with the $2.4 billion road came as welcome news to those in the business community who, as part of a long-standing debate, have argued that an east-west thoroughfare is needed to ease commuting and open development in northern Montgomery, Howard and parts of Prince George's counties.

Construction of the road would not prompt a land rush, developers and officials said, as much as it would cement and accelerate plans that are already in place and allow owners of existing buildings to push for denser redevelopment.

"You're not necessarily going to see tons more development right along the route of the intercounty connector," said John Shooshan, a major developer of office buildings in the area. "But it's going to free up the spokes to go forward in other areas."

Transportation ranks alongside the high cost of housing as one of the major problems cited by regional business leaders. But major projects such as the intercounty connector are inevitably divisive. While addressing a pressing need, they also generate more growth, more traffic and a push for even larger roads in the future. The connector, indeed, would serve in part as a sort of outer Beltway, relieving pressure on that older road near one of its more congested sections.

The biggest impact of building the new corridor, land-use lawyers and developers said, would probably come as property owners push for more intense uses of already developed land, particularly near the proposed highway's interchanges with major roads such as Georgia Avenue, New Hampshire Avenue and Shady Grove Road in Montgomery County.

"You'll see development happen at a faster pace once the ICC actually happens, and it's going to happen around the exits," said Stewart J. Greenebaum, president of Greenebaum & Rose Associates, a large office and housing developer in the area.

For the few swaths of undeveloped land that remain along the proposed highway, development officials say that they expect building to follow right alongside road construction. The project must still pass a federal review and is likely to meet opposition from local residents and environmental groups. State officials want to begin construction next year.

Along the intercounty highway in Montgomery, "there are some 10- or 15-acre parcels where there are development plans in place, and the road could help some of them get started because now they'll be able to say there's adequate [roads to handle] more development," said Robert R. Harris, a land-use lawyer for Holland & Knight LLP who represents several landowners with parcels along the corridor.

Other development hot spots are expected along Route 29, a major thoroughfare through Montgomery County into Howard County, and along the portions of Interstate 95 that run through Prince George's and Howard counties.

The connector "brings the high-tech communities in Howard County 30 minutes closer to the major economic engines of Bethesda and Montgomery County," said Richard W. Story, chief executive of the Howard County Economic Development Authority. He expects more companies will want to locate in the cheaper areas of western Prince George's and southern Howard. For instance, "if a company wants to be close to [the National Institutes of Health] but also close to Johns Hopkins, now it can be central to the two and get back and forth," he said.

One big winner with the highway project would be District-based developer Kingdon Gould III and his family, who own roughly 2,000 acres of land where the proposed highway intersects I-95 in Calverton. Gould's property is likely to have a major interchange on it or leading into it, although he stressed that he has come to no deal with state or county officials to sell parts of his land.

The property is oddly shaped. It runs roughly on both sides of I-95, from Route 198 in the north to Route 212 in the south. The intercounty connector would run through part of the southern portion of his property

Gould said he has owned the land for 20 years and plans to turn it from mostly sand and gravel pits into a mixed development called Konterra. It will become houses and retail and office space over the next two decades. Gould said he has developed about half a million square feet of office buildings, which he has leased to a range of tenants over the past few years, including small Internet-based businesses, engineering firms, and heating and air-conditioning contractors.

"The [intercounty roadway] will make it more attractive to certain tenants who want road access," said Gould, who also owns a site in the District near the Convention Center, where the city is considering building a mega hotel. "The ICC will change the market. It will make it easier for people to come and go and relieve all kinds of regional transportation problems."

North of Gould's Konterra project in Howard, planners and developers said, they are expecting quicker construction of an estimated 3 million square feet of commercial space at two large projects off I-95.

Housing is already being developed at Emerson, a major housing project that straddles I-95 at Route 216, and a nearby 600-acre development called Maple Lawn at Route 216 and Route 29. Emerson is being developed by General Growth Properties Inc. of Chicago, which bought out Columbia-based Rouse Co., and Maple Lawn is constructed by Greenebaum's firm.

Though Greenebaum's project is closer to a rejected northern route for the intercounty connector, he said the proposed road "will certainly benefit" his Maple Lawn project, along with other projects farther north. His company is building two office buildings -- about the size of four football fields -- for such tenants as law firms and government contractors, and he expects to start construction of an additional million square feet of office space.

In Montgomery, developers are expecting that some redevelopment will occur along Route 29 in White Oak, where a major new facility has been constructed for the Food and Drug Administration. And the intercounty road is likely to spur new development north around Interstate 270 in Germantown, Urbana and Clarksburg and as far north as Frederick.

"Upper Montgomery County is really going to be a force to be reckoned with," said Lawrence E. Thau, the managing director of the Bethesda office of CB Richard Ellis Group Inc. Companies will want to locate even farther north, Thau said, because the area will be easier to get to, with plenty of new amenities and a somewhat lower cost of living than lower Montgomery County.

"The workforce will change," he said. "You will have a number of highly skilled people looking at upcounty as a great place to work."

C. Robert Eaton, president of a nonprofit group that tries to attract biotech companies to Montgomery, said the county's high real estate prices and traffic problems at Interstates 270 and 495 have made it somewhat prohibitive to attract biotech employees from other counties. Now the new highway could make it easier.

"The potential employee pool is really going to broaden beyond Montgomery County," Eaton said.

Maryland Gov. Robert L. Ehrlich Jr., with state Secretary of Transportation Robert L. Flanagan, left, announced plans for the intercounty connector Monday. Local residents and environmental groups protested the road.