Just Add Water

Billy Penn's dream of a green country town comes true, simply by adding blue.

by Bruce Schimmel

P icture an urban neighborhood blighted by abandonment. A row of homes that looks like it's missing some teeth. Vacant lots that breed weeds, attract garbage and foster violence.

Now imagine that same neighborhood. Only this time, add some water. A small waterfall, washing over a bed of stones. A shallow pool with a burbling fountain. A tiny creek that meanders down the street, filled with fresh rainwater.

Billy Penn's dream of a green country town comes true, simply by adding blue.

Such is the vision of "Philadelphia: Waterwork," the winner of an urban design competition called "Urban Voids: Grounds for Change." Architects worldwide were asked to solve one of Philadelphia's most perplexing problems: what to do with this city's 40,000 vacant properties. Sponsored by the City Parks Association and the Van Alen Institute, the yearlong contest attracted 220 entries from more than 25 countries.

Four Philadelphia architects, Charles Loomis, Chariss McAfee, Juliet Geldi and Gavin Riggall, took the grand prize for a plan that envisions using storm water to rehabilitate urban wastelands. Their work is now on display at the University of the Arts, along with panels from all the finalists. (On the Web: Vanalen.org/urbanvoids, but try to see these in person.)

Most of the finalists propose fighting blight by filling the city's odd lots with lawns, gardens, even tree farms. And the Waterwork vision fits in nicely with this grander plan of greening. But it is especially elegant, because it uses one ecological problem to solve another.

Right now, Philadelphia has too many vacant lots and way too much storm water.

When an average summer storm slams our old sewer system, the sudden downpour overwhelms the city's wastewater treatment plants. During storms, oily street sewage is mixed with human sludge, and dumped into the Delaware River. That's bad for a river where bass, shad and other marine life are finally returning to this city's shores.

To deal with these deluges, the Loomis crew designed local urban waterworks to contain the excess rainwater, based on simple principles now used in large-scale projects in Germany and America.

The Waterwork plan can work in Philly for the same reason that Billy Penn originally choose this place. This city is a natural watershed. On its earliest maps, the land is crisscrossed by dozens of streams and creeks, which would capture, purify and return the water to the rivers.

These original streams also attracted awesome sewage. Early Philadelphians routinely tossed human and animal waste into creeks, which, along with the occasional dead horse, created periodic epidemics. By the 19th century, the city started filling most of those old streambeds with sewer pipes, which make up the main arteries of our wastewater system today.

As team architect Juliet Geldi puts it, their plan is to re-create that original ecology with a "new urban watershed" that would follow "the path of the water from the rooftop, through local cleaning and storage devices, eventually returning the water to the aquifer or to the Schuylkill and Delaware rivers in a clean state."

The plan uses waterworks like pebbled ponds and grassy swales to hold the overflow and purify the downpour. Their sketches of the neighborhood around Parkside Avenue and 51st Street show how canals and streams would carry clean water from neighborhood to neighborhood.

Waterwork would displace no one, because the new, man-made waterways respect the existing grid of streets. It's expandable and scaleable, because one-by-one, households would divert water from their roofs into neighborhood waterworks.

And since Philly is a natural watershed, the entire system of waterfalls, spray parks and streams would be powered by gravity. And, yes, they say, the moving water could also be used to generate power, just as it did up until the 20th century.

"Philadelphia: Waterwork" is a genius work of liquid beauty, and it's come just in time to enrich both the emerging Delaware waterfront plan and the city's "Greenplan" for sustainable open space. It's a vision of urban renewal that's as natural and lovely as the water that flows to the rivers, and the rivers that flow to the sea.

(bruce@schimmel.com)