Green city design in Portland
Qian Tianjian   Jan 23.2019
The ecological environment policy of Portland can be traced back to 1970s. Thanks to this, Portland has preserved a large number of suburban forest resources as an ecological filtration barrier. At the same time, in the central area of the city with increasing density, Portland has retained many parks and open spaces, and a large number of vegetation has also reduced dust pollution. The transportation system of Portland is characterized by closely connected public transport system and slow running system.


Portland is located in Oregon, western United States, near the mouth of the Columbia River, and is the second largest city in the northwest of the United States. Its unique geographical location has created a special climate in Portland. Portland is known as "river city" because of its numerous rivers and streams. In such a city where rainfall is abundant and rivers are densely distributed, the efficient operation of storm water management system has become the focus of urban development. After about half a century of development, Portland has formed a unique and mature urban ecosystem.

Reason to Be Selected

In 2008, the Grey to Green project not only involved in building a new green infrastructure, but also related to sustainable rain and flood management and public education activities. Through close links between them, a set of self operating urban ecosystems is formed.


Green infrastructure constructionn  

Green Street strategyn  

Building mono and ecological roof constructionn  

Grey to Green project


Green infrastructure construction: Green infrastructure refers to facilities for collecting and managing rainwater through plants and soil,including green streets, ecological roofs and rain gardens. In Portland, the main contents of the construction are green street and building monomer rain and flood management.
Green Street strategy: In addition to the construction of street facilities, Portland is promoting the "Green Street" management group plan in the community.The plan encourages businesses or individuals to help care for street greening and beautifying the community. The environmental services bureau is responsible for monitoring infrastructure performance and improving design, and reduces maintenance costs through community and government coordination. At present, 867 Green Street management teams have been set up in Portland, and more teams are continuing to form.

Building mono and ecological roof construction: Since 2008, a total of 191 ecological roofs have been built in Portland, covering an area of about 11 acres,which is equivalent to the size of 8 football fields. Hundreds of gallons of rainwater will be absorbed by the ecological roof before reaching the ground,and then flow into the planting pool or grass ditch through the down pipe. At present, more than 300 ecological roofs are still in the design and construction in Portland, and the ecological roofs will be paired with the photo voltaic panels or designed as birds' habitats to maximize their benefits.

Grey to Green project: In the five years of the "Grey to Green"project, more than 32200 new trees and roadside trees were added in Portland.These trees will capture more than 18 million gallons of rain every year. The Portland Environmental Protection Bureau conducted a survey on the less greening communities through volunteers, and drew up the available planting space according to the residents' opinions.The promotion and publicity play an important role in the community, and the participation of the volunteers has saved a lot of funds, and the promotion of the concept of rain and flood management also makes it possible for the project to be carried out smoothly in some private gardens.


For the government, Portland's green planning is a long-term project that has been going on for 70 years. In this process, Portland's urban ecology is constantly improving. For the citizens of Portland, rain garden and urban ecological maintenance are not just newspaper headlines, but a way of life. The public participates in the maintenance and maintenance of the green infrastructure, which makes the street facilities well protected, and the management department can also monitor the effect of the rain and flood management. 



The city of Portland
TOPICS | Portland | Ecocity| Composive


Pinkbike@wild BLUE Bear

Lat: 45.5142
Lng: -121.341
Region: NorthAmerica
Scale: City
Field: Compositive
City: Portland