Copenhagen, the capital of Denmark situated on the coast of the Øresunds region that connects the North Sea with the Baltic Sea, is vulnerable to sea level rise, warmer weather and more weather extremes in the future, including heavy rain events. Spurred by a series of highly damaging cloudburst events, including the July 2011 cloudburst that caused damages worth close to €1 billion, Copenhagen needed a better way to manage the water inundating the city during these downpours. In 2011 the City of Copenhagen adopted the Copenhagen Climate Adaptation Planxxvii, complemented by the Cloudburst Management Planxxviii (2012) detailing the methods, priorities, and measures related to adaptation to extreme rainfall events.


Copenhagen was able to work with water utility on a comprehensive restructuring of the Copenhagen drainage system (including separation of rainwater from waste water) and streetscape, in order to turn roads into rivers in the case of extreme rain (part of Copenhagen’s “storm water plan”) and direct water to outlets and retention basins. This is complemented by greenscaping, in particular through implementation of the Sustainable Urban Drainage System – building of green gardens, rooftops and bioswales to prevent rainwater from flowing directly into sewers.

Reasons for success

There are three main reasons for Copenhagen’s success. First, the city had experienced repeated extreme weather events, which created political buy-in for change. Second, the Copenhagen government showed budget creativity by pushing for a change in national level legislation to allow the use of revenues from a water-use fee combined with private financing and revenues from taxes for investment in the water management system. Finally, presenting the adaptation measures under the “improved city green space” frame stimulated great enthusiasm and acceptance of major city infrastructure overhaul. 

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  • Environmental
  • Health
Key Impact
Presenting the adaptation measures under the “improved city green space” frame stimulated great enthusiasm and acceptance of major city infrastructure overhaul
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