As urbanization continues, natural landscape is removed and covered with imperious surfaces, which constrains rainwater infiltration to the ground. During rain events, the water could flood low-lying area in the urban area, also the flood could pick up the surface pollutant then directly goes into the nearby water streams. With the help of the grey infrastructure, i created by modern engineering, has reduce the possibility of flooding, however, at a cost of eliminating the natural inhabit for wildlife and preventing natural water circulation.
Rotating the approach to increase the resilience of urban environment, we have adapted more sustainable green infrastructure to encounter heavy rain events, like green roofs, bioswales, and rain gardens, etc. The most interesting green infrastructure design I have ever seen was the one in St. Kjeld neighborhood of Copenhagen. The city has experienced extreme flooding before, so citizens understood how important resilience means to them now. The bicycle infrastructure design shows the structure could be used as a water trench during the rain event when the water outflows the bio-stream along the street. It would be a little challenging to pedal through the water, anyhow, cyclists wouldn’t mind, I think, since they probably be wet already.
Imagine 1-St. Kjeld Neighborhood Bike Infrastructure Conceptual Design
(Source:http://www.dezeen.com/2012/08/18/saint-kjelds-climate-adapted-neighborhood-by-tredje-natur/, dezeen Magazine)
Another idea for the bicycle infrastructure in Copenhagen-the conceptual design is integrated with the stormwater trench beneath the pervious pavement, and the trench could redirect rainwater out of the neighborhood through the slope. The idea is great to reduce the local flooding efficiently, however, it could exacerbate flooding in other low-lying part of the city or downstream. We will definitely experience more severe rain events, so keep exploring new green infrastructure and create more resilient cities would be inevitable. And I think green and grey infrastructure should work together to better adapt to climate challenges.
Imagine 2-Conceptual Bicycle Trench Design
i. Watershed Management Group, Green Infrastructure for Southwestern Neighborhoods, Version 1.2, Revised Oct, 2012. P4.