Soaring real estate values in the South Side quantify what many people already knew: The South Side is successfully transforming itself from a declining industrial community into a vibrant urban neighborhood.

Between 1990 and 2000, the median value of houses in the South Side Flats, the neighborhood along the Monongahela River, has risen from $30,979 to $74,959, according to census figures compiled by Laura Beres of the nonprofit South Side Local Development Co.

That's a 142 percent increase.

The median value of homes on the South Side Slopes rose from $24,842 to $42,578, a 71 percent increase, said Beres.

During the same period, Beres, a business policy specialist, said the median value of homes across the city rose from $40,500 to $59,700, a 47 percent increase.

While rising real estate values in the South Side is good news, Rick Belloli, executive director of South Side Local Development Co., said longtime residents don't want to be priced out of their own neighborhoods.

"The danger is that we don't want to displace existing South Siders because of accelerating property values," said Belloli, who heads an organization that was one of the key catalysts and early believers in the transformation of the South Side.

The impact of rising real estate values on the South Side is one of a half dozen policy issues fueling recommended changes to the South Side Neighborhood Plan, the blueprint for the neighborhood's future.

"One of the greatest things about the South Side is its diversity," Belloli said. Today's South Side is part old-timers, part college students, part young professionals looking for a hip, convenient area in which to live.

New construction in the South Side Flats is expensive; condominiums under construction are priced at more than $200,000 per unit.

As part of proposed revisions to the neighborhood plan, a committee has recommended that the plan include new language calling for developers to set aside 10 percent of any new developments of 10 housing units or more in the Flats for "affordable housing." Belloli and Beres presented those recommendations to the public at a series of recent meetings.

While Belloli acknowledged that the group can't force developers to comply, he said that it is important to spell out the community's view in the neighborhood plan, so it will help guide future decisions made about planning, zoning and overall development.

The South Side Neighborhood Plan, adopted in 1990, is updated periodically to keep it current. Final changes to the plan will be voted on by the South Side Planning Forum and the new version will be used by stakeholders to set the agenda for the future.

"It is used to make sure this is a consensus about what people want to see," Belloli said.

In addition to changing demographics, other revisions relate to parking, reuse of public facilities, such as the South Vocational-Technical High School which recently closed, new opportunities for the upper levels of retail shops on Carson Street and preservation of green space.

If the upward trend in real estate values continues, Belloli said, by the 2010 census, the South Side may not be eligible for some of the federal Community Development Block Grant money that currently comes into the area. But that's a story that will be written in future plans.

A draft of the South Side Neighborhood Plan can be found online at www.southsidepgh.com or by visiting the Carnegie Library, South Side Branch, 2205 E. Carson St.

"The community coming together and speaking with one voice through the neighborhood planning process has been a hallmark of the revitalization of the South Side," Belloli said.