Portland’s Green Streets Project
In the early 2000s, Portland launched a program called the Green Streets Program. Hoping to better manage the stormwater that cycles throughout this immense urban area, they began implementing infrastructure that would capture as much water as possible. But what are Green Streets?
Green streets are streets that use soil, plants, and other natural systems to captures runoff. They are typically placed between the sidewalk and the street, which are angled to make water flow to such plants. Then, this water slows the flow of the water, and filters it before it enters the stormwater system.
One of the major benefits of this is that it prevents storm drain blockage. By slowing the flow of the water, it reduces the strain on the storm system pipes. Also, by filtering out large debris, it mitigates the clogging of these same systems.
Also, it helps reduce the work of filtration systems when turning runoff into potable water. It was found that these systems remove up to 90 percent of pollutants from the stormwater, and removing large amounts of trash from the water.
One major example of these green streets in Portland is the NE Siskiyou Green Street. Using Oregon grape, sword ferns, and other plants, this project transformed about 1000 square feet of land into a vegetation-based storm drain. It was calculated that this Green Street saved around 85% of the water that landed on the area, and saved around $250,000 since its installation. This is a great deal of savings when compared to the general cost of a green street, which is valued at $20,000. Also, during a recent storm, the system saved 9,400 gallons of water during that storm alone.
The many Green Streets in Portland represent a minor shift that can greatly improve the sustainability of a city. With the use of standard retrofit technology, any street can be turned into a Green Street. And especially in areas facing water-shortages, this simple form of infrastructure can save not only thousands of dollars, but it can also help water management professionals avoid uncertainty pertaining to water safety and security.
