| Most green roofs are high above the street and out of sight. The Philadelphia Water Department's green roof bus shelter gives people on the street a chance to see and experience green roofs. Green roofs offer many benefits—they help to ease the summer heat and reduce the amount of rainwater that makes its way to the sewer. When we capture rainwater or slow the flow to storm drains, we can reduce the pollution and flooding that impacts our streams and rivers. Green Roofs are just one of many green infrastructure tools PWD is using to transform the health of our city and our waters. From proper vehicle maintenance to installing a rain barrel, there are many ways that you can contribute to these efforts, too. The goal of this project is to inspire individuals to take on their own green stormwater management project at home and in their community. Find out what you can do with our online guide to green stormwater tools. Download a fact sheet on the Green Roof Bus Shelter. |
The Philadelphia Water Department wants to acknowledge its partners for making this project possible: Mayor's Office of Transportation and Utilities, Mayor's Office of Sustainability, Titan, the Pennsylvania Department of Environmental Protection (Coastal Zone Management Program) and Roofmeadow, Inc. Roofmeadow is a leader in the green roof industry and generously donated their time to design, install and maintain this lightweight and durable green roof. The following companies also donated materials for the bus shelter's living roof: Huesker Inc., GSE Lining Technology, SkyGarden and Sempergreen.
This demonstration project represents the vision of Green City, Clean Waters and the efforts of Greenworks Philadelphia. Green City, Clean Waters is PWD’s plan for managing stormwater through primarily green infrastructure to meet water quality standards while creating economic, social and environmental benefits. Greenworks Philadelphia is Mayor Nutter’s plan for improving our city's environment, reducing energy use, creating jobs and enhancing our quality of life.
Each layer of a green roof system plays a critical role in managing rain water and protecting the building beneath it.
Vegetation layer - the vegetation layer is made up of a variety of sedum species and plugs of perennial plants. This layer is pre-grown. To protect the young green roof plants and media from blowing in the wind, a photodegradable wind net is placed over the newly planted roof.
Growing medium - the lightweight soil (media) supports robust plant growth. Media is deeper in the corners above the bus shelter steel legs, where more weight can be supported.
Capillary fabric - to enhance water retention, we've added an engineered fabric that holds and evenly distributes water.
Root barrier - base green roof layers protect the roofing from roots and mechanical damage.
Reinforcement layer - water-resistant corrugated steel roof to both protect from the elements and facilitate drainage of excess water from the back of the shelter. A rigid mat above the metal roof creates a flat surface to support the rest of the green roof layers and a plastic sheet above the rigid mat holds the majority of rain water in the soil.