Philadelphia
Big pipes to drain off stormwater aren’t necessarily your friend. They may even be the reason the stream or river near your home isn’t fit for swimming.
The message may sound strange to communities recently hit by torrential rains, or threatened by oncoming tropical storms. But the green revolutionaries of Philadelphia’s Office of Watersheds are expounding a new philosophy of sustainable water management – to adapt city parks, roadways, school sites, lawns and yards so that they absorb and slowly filter out as much rainfall and stormwater as feasible.
Why? First, to stop stormwater from flooding drainage systems and sending untreated sewage into local rivers and streams. Second, to minimize the fast, storm-induced runoff by pollutants that gather on a city’s concrete and asphalt surfaces – litter, oil and antifreeze leaked from cars, pesticides, corroding metals from junkyards, bacteria from pet waste. All these are top sources for the generalized, “non-point” pollution that makes so many local beaches dangerous for swimming.Finally, heavy storms choke off streams and pollute the waterways with sediment from scraped-off land, construction sites and improperly protected farm fields.
Cities’ usual way of dealing with stormwater has been to collect and move it off-site as rapidly as possible, often with big, expensive tanks and tunnels to hold the overflow and its sediments as long as is feasible. Several major U.S. cities are building precisely such facilities right now. But the Philadelphians are aiming instead to make their entire city into a kind of great green sponge, an urban ecosystem that can handle its stormwaters and wastes far more naturally and, in the process, ensure clean water for fishing, swimming and drinking.
The holistic thinking has been spearheaded since 1998 by Howard Neukrug, founding director of the city’s Office of Watersheds. Rather than focusing on new pipes, for example, Neukrug’s office puts a priority on cleanup, preservation and easy public access to the parks.
Why? The Schuylkill River and several of its tributary streams, source of Philadelphia’s water supply, run through massive Fairmount Park and other city parks. Parklands, says Philadelphia watersheds planner Glen Abrams, are like kidneys, performing natural restorative work for a city’s water systems. But if streambeds are degraded and trash-filled, if citizens can’t enjoy the waters, who’ll fight to keep the parks’ waterways clean, fishable and swimmable? Across the city, the watersheds office pushes its green, natural agenda. It advocates “stream daylighting,” for example – bringing old streams, buried in culverts, back to the surface and recreating their banks and natural habitat. It encourages environmental stewardship of Philadelphia’s large supply of vacant land, pushing for introduction of little swales and bowls and berms to make the sites better short-term repositories of stormwater. There’s a “campus parks” initiative to help the public schools redeem ugly asphalt-paved schoolyards with greenery and renew basketball courts with newly developed asphalt that rather amazingly absorbs rather than repels water.
The agency is also working with the street department to redesign traffic triangles, street medians and right-of-way land to minimize runoff and absorb water more naturally. It’s advocating “rainwater harvesting” – rainspout barrels homeowners can attach to water downspouts and use later for garden watering. It’s pushing urban gardening, advocating green roofs, creating nature-friendly master plans for former industrial riverfronts. And when the watershed crew discovered a huge colony of geese flocking onto land above a water intake and dropping as much as 36 tons of waste there annually, it repelled the unwelcome feathered visitors by planting high meadow grasses that geese studiously avoid.
Philadelphia’s quandary is that the Schuylkill flows over 100 miles, draining portions of 10 counties and 2,000 square miles before it reaches the city. So the Philadelphia Water Department conducted a source assessment, including analysis of water quality at 52 intake points up and down the entire river. Then the Philadelphians formed a Schuylkill Action Network with federal and state agencies and upstream communities.
The network is pinpointing issues from abandoned mine discharges to agricultural abuses. Neukrug also warns against suburban sprawl that destroys buffering landscapes and increases stormwater runoff.
The effort is new, its challenges immense. But here’s an exciting national model: how a city enhances its environment, safeguards its water lifelines, engages federal and state agencies, and leads a region.
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Correction: The tripling of coal prices in the last eight years, reported in my Aug. 6 column on coal burning plants, was in error; the actual increase has been 36 percent.
