As outlined in the City’s Green City, Clean Water Plan, Philadelphia is investing $1.6 billion over the next several decades to significantly reduce Combined Sewer Overflows (CSOs)—a combination of sewage and stormwater that overflows into rivers and streams when it rains—in order to meet obligations required by the Federal Clean Water Act. Much of this effort will focus on reducing the amount of paved impervious cover in the City and replacing it with vegetated and pervious features.
Green Streets are streets that mimic natural processes so that less stormwater enters the combined sewer system, ultimately reducing CSOs. Landscape, paving, and engineered materials are used to capture, slowdown, filter, and reduce stormwater run-off. Because streets and sidewalks account for approximately 38 percent of the City’s total impervious cover, the creation of a Green Streets Design Manaual was a significant component of Philadelphia Water Department’s Green Stormwater Infrastructure Program.
HOW WE HELPED
McCormick Taylor served as the Steering Committee Facilitator for the Manual. The Manual details the main design elements used in creating Green Streets that are readily accepted by city agencies.
In addition to identifying ready-to-use reproducible design details of green stormwater infrastructure, the Manual outlines the regulatory process for streetscape designers that should be followed with the city for both conventional and innovative approaches.
A public outreach process with both technical and stakeholder committees was designed to shape the outcome of that manual, so it is supported by relevant agencies, organizations, and innovative approaches.
The Green Streets Design Manual outlines what types of green stormwater infrastructure practices are appropriate on various street typologies, provides standardized design details, and lays out the necessary design review and construction inspection processes. Moving forward, design professionals, engineers, planners, and developers can utilize the approved design standards and procedures therein to expedite green street development in Philadelphia.