Green- infrastructure

The Economist wrote an article 11 nov how sewage water overflow regularly in big cities like New York, and how the city can solve the problem, not by invest into pipes but to plant trees,

New York recently unveiled a grand plan to clean up its waterways. Instead of spending billions on new tanks and pipes (ie, “grey infrastructure”), which take years to build and never quite address the problem, the city intends to invest in “green infrastructure”, such as roofs covered with vegetation, porous pavements and kerbside gardens.
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David Beckman at the National Resources Defence Council is optimistic. “Usually we’re plaintiffs,” he says, “but here we’re collaborators, working with the city.” Finally cities are finding ways to handle storm-water that needn’t involve holding one’s nose.

Read the full article, Trees grow in Brooklyn- A natural form of relief for overworked city sewers