Philadelphia moves ahead with 25-year water-management plan

Philadelphia got the green light Wednesday for a $2 billion storm-water plan that will transform the way the city deals with rain.

The 25-year plan, which has been hailed as a national model, envisions green roofs on office buildings, porous pavement on city streets and parking lots, and plants and trees with tubs of gravel below ground to hold water and stall runoff in a storm.

All would be designed to let rainwater seep back into the ground rather than gush into an aged sewer system where it mixes with raw sewage and overflows into streams and basements.

Officials of the city Water Department and the state Department of Environmental Protection on Wednesday signed a consent agreement - constituting official approval of the plan - in the atrium of the DEP regional headquarters in Norristown. In front of a 5,000-gallon cistern that collects rainwater for flushing the building's toilets, they clinked glasses of public water in a toast.

Called "Green City, Clean Waters" and proposed in 2009, the plan "is our pledge and our investment to make our rivers and streams fishable, swimmable, and breathtaking," said Howard Neukrug, the city water commissioner.

The agreement "signals our recognition that the best way to manage storm-water runoff is to control it at its source," said Jenifer Fields, head of the DEP's regional water-quality program.

Although the plan remains controversial among some business owners for its fees, it has the mayor's support.

Officials contend the plan - because of all the trees and plants - will help beautify the city, revitalize neighborhoods, clean the air, cool the region, and save energy.

They also say the plan is cheaper and better than the route some cities have taken - building miles-long underground tunnels that act as giant reservoirs for storm water until it can be gradually pumped out and treated at a sewer plant.

"It's extremely innovative," said Robert Traver, a Villanova University professor of civil engineering and a national storm-water expert. "Other places are watching this, and they're going to be following our lead."

Some projects are already in place. Far more are coming.

The problem the plan attempts to solve is called "combined sewer overflows."

While some cities have separate systems - one for regular sewage, another for storm water - most of Philadelphia has a combined system, sending all water waste into one matrix of pipelines.