As little as a tenth of an inch of rainfall can be enough to overload sewers in some Pittsburgh neighborhoods, leading to the potential for untreated sewage to flow into area streams and rivers, according to James Stitt, Pittsburgh Water and Sewer Authority sustainability manager.
The PWSA has awarded 17 grants totaling $250,000 to local businesses and community organizations for various projects which aims to reduce the amount of yearly storm water runoff throughout the city by more than 3.5 million gallons.
“The storm water enters our combined sewer system,” Stitt said. “It mixes with sanitary sewage that’s already in that system, and then during heavier rainfall events, it actually overloads that system and flows into the rivers and streams as a release point.”
The grants cover a variety of approaches, said PWSA executive director Jim Good.
“There’s rain gardens, there’s bioswales, which looks like a little hill and it’s used to slow down and capture water, and then another big approach we see is the use of pervious pavement that allows water to percolate into the ground, rather than wash off into streams,” Good said.
He said homeowners can also
manage storm water by collecting rain in barrels and constructing rain gardens of their own.
Megan Zeigler, PWSA green infrastructure technical coordinator, said an effective rain garden includes drought resistant plants such as day lilies along a raised outer edge, and a sunken section in the middle with plants such as switch grass, magnolias and sedges, which are all effective at absorbing larger quantities of water.
Some grant recipients include Pittsburgh Housing Development Corporation for rain gardens and barrels, Phipps Conservatory for installation of a storm water reuse system and Tree Pittsburgh for a 2,000 gallon rain water collection cistern.
Stitt said these projects are important because there is no such thing as “taking storm water away.”
“When we put it in a pipe and take it away, it doesn’t go away,” he said. “It goes somewhere else and someone else has to deal with it.”
Joel Perkovich is working with grant-recipient Start Uptown to transform the roof of the Paramount Film Exchange building into a rain garden that he said will manage at least 60,000 gallons of water per year.
“The roof is going to be a highly visible and accessible demonstration of how to provide source control with storm water in a densely developed urban area, but also to harvest it as a resource and use it to support native plant communities, pollinators (and) food production,” Perkovich said. “So it’s really going to be a potent example in a small space.”
Grant Ervin, City of Pittsburgh sustainability manager, said he wants to see Pittsburgh at the forefront of storm water management.
“Other cities are out in front in terms of the policy and the practice of using green infrastructure,” Ervin said. “Whether it’s cities in northern Europe like Rotterdam, or just across the state in Philadelphia … we see the opportunity as the city to really not just learn from them, but to leapfrog them.”
