Now that the county commissioners of southwestern Pennsylvania have a defined road map for spending $33.3 billion in federal and state tax dollars for infrastructure and development between now and 2035, will they use it:

• On more urban sprawl? Since 1982, nearly half as much land in our 10-county region has been built on, paved over or otherwise developed as in the entire two centuries before -- while the population was declining by 8 percent.

• Or for "smart growth?" That is, slowing the pace of sprawl to achieve greater social equity, environmental quality and economic prosperity?

I asked these questions in an October 2003 Post-Gazette column, "The $33.3 billion question." They are still pertinent, especially in view of the rising cost of gasoline.

Fortunately, there is one big difference since then. The Southwest Planning Commission has now completed and published "Project Region," subtitled "2035 Transportation and Development Plan for Southwestern Pennsylvania" (www.spcregion.org/proj). It covers a vast array of topics beyond roads -- air quality, preservation of agricultural land, the recovering of old industrial sites, tourism, the attraction and retention of young people, etc.

Of particular significance, the plan emphasizes growth in existing town centers -- whether the region's 10 county seats or the aging milltowns in our valleys -- thereby preserving open space and agricultural areas. It also promotes transit use, ride sharing and other fuel-efficient transportation strategies, as well as initiatives to reduce air emissions.

Why is this important? Because the SPC is the federally designated "decider" of where that $33.3 billion will be spent.

The SPC is a 66-member body of representatives (including county commissioners and their appointees from Allegheny, Armstrong, Beaver, Butler, Fayette, Greene, Indiana, Lawrence, Washington and Westmoreland counties, plus the mayor of Pittsburgh and certain state appointees). But the real power rests in its 14-member executive committee -- representatives from each county, usually the county commission chair, Pittsburgh's mayor and three appointees from the Allegheny Conference on Community Development.

But the big question remains: Will these officials, especially the key county commission chairs, stick to the laudatory aims of "Project Region"? Will they stand fast against the jostling of municipalities desperate for any kind of development to enhance their tax bases, whether 1-acre housing or the malls that have eroded the commercial vitality of such county-seat towns as Greensburg, Butler, Washington and Uniontown? Will they be judicious in approving the sprawl-enhancing roads and sewer lines for which developers lobby?

James Hassinger, executive director of SPC, is optimistic about Project Region's future. He points to the unusual amount of participation that went into the plan (more than 3,000 participants from 100 citizen and governmental groups). That accomplishment won for Project Region the 2008 Public Outreach Excellence Award from the National Planning Association. There will be both support and watchfulness from these participants.

The SPC head also points to Cranberry Township's decision to revise its zoning system to what is called a form-based code, with mixed-use components designed for higher density. Describing its "sustainability" goals, the Cranberry planners declare, "Their essence is to plan as though the community is going to be around a long time. That means planning which doesn't encourage development that would hurt future generations."

Mr. Hassinger also feels that some developers are emerging who accept the concepts of "smart growth," rather than attempting to bulldoze past them.

As to older communities, Mr. Hassinger points to Greensburg's railroad station and the Piatt development in downtown Washington as examples for future activity. Turning to transit, Mr. Hassinger says SPC has added a staff person to work with a transit operators committee, with an early focus on developing a smart-fare card that could be used by patrons in any of the region's transit systems -- including those in Westmoreland, Beaver, Butler, New Castle and the Mid-Mon Valley -- something that would provide linkages to such job centers as Pittsburgh and Cranberry.

Another critical issue is managing the water and sewer services essential for suburban developments while dealing with the flooding problems they sometimes create downstream. The Institute of Politics at Pitt has just completed a comprehensive study of the subject by a Regional Water Management Task Force chaired by President Jared Cohon of Carnegie Mellon University. Mr. Hassinger said SPC may use that report for future action.

It's significant that Mr. Hassinger will be a major speaker at Sustainable Pittsburgh's 8th annual Smart Growth Conference May 16. The subject of that meeting at the Omni William Penn Hotel will be: "Revitalize the Region: Seize Market Interest to Redevelop Core Communities."

Back to the SPC commissioners. At the end of the 1787 Constitutional Convention, Benjamin Franklin said this about its signal achievement: "A republic, if you can keep it."

Applied to the SPC, "You have written a great plan. Will you keep to it?"