WHEN the National Road reached the Monongahela River and Brownsville, Pa., in the early 1800s, the town thrived as a gateway to the frontier. When the railroads came in the 1850s, the traffic moved to Pittsburgh and that city boomed.
Now, southwest Pennsylvania is hoping transportation will work its economic magic again as the area revamps Pittsburgh's old and crowded airport.
The $600 million Midfield Terminal Complex is the biggest public-works project in western Pennsylvania history. Except for the new Denver airport under construction, it is the largest airport project in the country. The October 1992 opening promises to bring growth for local business as well as air traffic, Pittsburgh development officials say.
``The potential of this airport is virtually unlimited,'' says Stephen George, head of the Allegheny County Department of Airport Area Development.
``The focal point of economic activity is going to move to that part of the county,'' says Jake Haulk, senior economist with Mellon Bank in Pittsburgh.
The current airport looks like a relic from a bygone era. Its small, U-shaped drive may have been elegant when it opened in 1952. Today, it is jammed with traffic at peak periods. The number of passengers using the Greater Pittsburgh International Airport has doubled since 1979.
Strictly speaking, the project is a renovation instead of a new airport. Two terminals will replace the current facility. Passengers will arrive by a brand-new highway to the land-side terminal. An underground people-mover will then whisk them to the air-side terminal. The facility will have 78 gates, expandable to 100 gates.
The ability to expand is a vital selling point at a time when airport space is at a premium in the United States. The last airport to come on line was Dallas-Ft. Worth in 1974. Only one new airport - at Denver - is under construction. It is expected to open in 1993 or 1994.
Meanwhile, traffic continues to grow. In 1988, 21 airports saw aircraft delays of 20,000 hours or more. The Federal Aviation Administration (FAA) projects that 41 sites will have that dubious distinction by 1998. Many hubs, already bursting at the seams, have little room to expand.
The Pittsburgh airport, by contrast, has the land to add two runways to its current four. It can extend its people-mover and build a second midfield terminal. Development officials here hope this will help them lure foreign airlines and make Pittsburgh a tourist's alternative to the more crowded East Coast airports. In 1988, Pittsburgh was the nation's 12th busiest airport. By 2005, the FAA expects it to rank 6th.
That kind of growth would mean lots of new jobs. A new Midfield Terminal would double airport-related employment from 10,000 to 20,000 and indirectly boost area jobs from 20,000 to 40,000, says Scott O'Donnell, Allegheny County's aviation director.
The region could use the economic boost. While Pittsburgh and some of its suburbs blossomed during the 1980s, the metropolitan area as a whole suffered from the loss of steel and manufacturing jobs. The five-county region lost 195,556 people, 8 percent of its population, during the 1980s, according to preliminary 1990 census figures. The metropolitan area slipped from 13th largest in the US in 1980 to 19th in 1988, the Census Bureau finds.
A new airport will not automatically turn things around. Some hubs, such as Atlanta-Hartsfield, have spurred tremendous growth; others, such as Kansas City, have had less success, says Andrew Goetz, a University of Denver geography professor who has studied airports and development. To succeed, cities need a strong airline that will make the airport its hub, Professor Goetz says. Pittsburgh, with USAir, seems in better shape than Kansas City, which had ailing Eastern Airlines. Highway access, another key factor, will be improved by projects such as the expansion of the Beaver Valley Expressway, officials say.
``In the long run, having that airport larger, more accessible, and more full-service is something that small companies in western Pennsylvania are going to be able to use,'' says Leo Spaeder Jr., of Penn's Southwest Association, a nonprofit economic development corporation. Development around the airport is still in its infancy. Of Pittsburgh's 351 new or planned construction or renovation projects since 1987, only 78 are within the 100-square-mile airport area, Mr. George says.
Some communities worry that the airport project will draw development away from them, says Mame Bradley, assistant manager of Allegheny County's economic development division. ``We have to be very, very concerned that the benefits of the airport get as far as the [Monongahela] valley.'' The river communities are still recovering from the steel mill closings.
``It's not an absolute thing,'' Goetz says about transportation-based development. ``There are lots of other things that are important to city growth.''
``This could be the greatest thing since marmalade on toast,'' adds Mr. Haulk. ``Or it could end up with people saying: `Why did we spend so much money on this thing?' ''