Plan calls for Liberty Bridge stormwater to flow into rain garden near Downtown courts building
The Pennsylvania Department of Transportation plans to pipe stormwater from the Liberty Bridge into a rain garden near the Pittsburgh Municipal Courts Building as part of a department initiative to control runoff, officials said.
Similar plans are under way in Philadelphia and the Carlisle area, and soon will include construction projects across the state, according to PennDOT spokesman Rich Kirkpatrick. The Liberty Bridge rain garden is the first of its kind in Western Pennsylvania.
“Philadelphia got started a little earlier because the city came under some prior regulatory mandates, but now, it's coming statewide,” Kirkpatrick said.
Three Rivers Wet Weather, a nonprofit environmental group established to address the region's stormwater problems, pitched the idea of a rain garden to PennDOT's District 11, spokesman Steve Cowan said. Officials agreed to include it in an $84 million Liberty Bridge reconstruction starting this year, he said.
PennDOT won't know how much water will flow into the garden until it finishes the design, he said.
The garden is expected to cost $45,000 and is subject to approval by Pittsburgh City Council and the Pittsburgh Parking Authority, which owns the property. It's planned for a grassy area bordered by the bridge between the courts building and Three Rivers Heritage Trail and will be visible to trail users.
Beth Dutton, program manager for Three Rivers Wet Weather, said the rain garden would filter salts, oils and pollutants deposited on the bridge. Water would be absorbed by plants and drain naturally into the ground, she said.
“Rather than all of that going directly into the river, it will be captured by the mulch and soil in the rain garden,” Dutton said. “What was so great about that location is it's a very public location, and it's right along the trail.”
A federal mandate requires municipalities to cut amounts of sewer and rainwater flowing into streams and rivers.
The Allegheny County Sanitary Authority is planning $2 billion to $3 billion in infrastructure improvements to reduce 9 billion gallons of runoff annually by about 50 percent during the next 10 years.
Pittsburgh and Allegheny County officials and community activists have lobbied Alcosan and the Pittsburgh Water and Sewer Authority to include environmentally friendly infrastructure to reduce runoff before it reaches sewers.
Bob Bauder is Tribune-Review staff writer.