South Philadelphia's neighborhoods and community groups are donating the people. The Phillies and the Eagles are donating "Keep FDR Park Clean" T- shirts and hats. McDonald's is donating the lunches. Coca-Cola is donating the cold drinks. Somebody or other is donating thousands of celebratory balloons.
And the 350-acre park, which has fallen upon hard times of neglect and disrepair in recent years, will supply the litter, the once-pristine fields and meadows dotted with beer cans, and the debris-strewn shores of several dirty lakes.
The junk includes old tires, beer cases, picnic litter, bottles and cans, and a landfill's worth of the usual debris of an urban park that people use but don't take care of.
"South Philadelphians have used this park for decades," said U.S. Rep. Thomas M. Foglietta. This park, noted Foglietta, is known by most South Philadelphians as simply "the lakes."
Foglietta, who came up with the cleanup idea, plans to pitch in on Saturday with everybody else.
During a tour of the park the other day, Foglietta pointed out lakes he had fished in and trails on which he had ridden his bike while growing up in South Philadelphia.
"This is the only place in South Philadelphia to get away from the city," he said. "We don't think for a second that we're going to turn this park around with a one-day cleanup, but the idea is to get everybody involved, get people thinking about the park and how nice it used to be, and get people to start bringing their families here again."
To organize the big cleanup, Foglietta chose a well-known South Philadelphia community activist, Joe Cascerceri of the Mayor's Commission on Neighborhoods and Foglietta's South Philadelphia coordinator.
And Cascerceri, an Army veteran, said he plans to approach the job with military thoroughness. "This park is the working man's recreation center," he said.
"We've got a half-dozen city sanitation trucks coming. We've got shovels, trash bags, cleaning equipment from the city. We're going to sweep the park in that old reliable Army policing technique - break up into groups, cover every inch of the ground, and if it's not growing out of the ground, pick it up."
Foglietta said he first envisioned a staff and public picnic as a way of drawing public attention to the park's current plight. But he dropped the picnic idea after seeing the park's condition.
"Remembering the way I knew it as a kid, we realized that the best thing to do was to try to involve the entire South Philadelphia community in bringing back 'the lakes.' "
The park at Broad Street and Pattison Avenue, near the current site of the sports complex, was born in 1926. A recreation area of hundreds of acres of filled-in swampland was created for the city's Sesquicentennial celebration. It was known for decades as League Island Park, and in the mid-1940s after Roosevelt's death, was renamed.
The park is now operated by the Fairmount Park Commission, which enthusiastically supports the cleanup plan because it has pumped more than $1 million into park renovation, including improvements to tennis courts and baseball and softball diamonds, commission officials said.
But until now, Foglietta said, nobody has been able to keep up with the litter.
"All the facilities for picnicking, fishing, boating, having fun are already here, and it's not that the park and its grounds and meadows are filthy, rotten or grimy - it's just full of the junk that people have left here for years.
"Here's a problem that is absolutely not the city's fault. It's just that people who use the park have to be convinced that once it's cleaned up, it can stay that way and be more enjoyable for everyone."