Climate change: Copenhagen declares war on floods

Over the next 20 years the Danish capital plans to invest some € 1.5 billion to protect the city against coming cloudbursts. The planned infrastructure measures comprise 300 individual projects designed to make Copenhagen resilient against future extreme rainfall. Drees & Sommer was supporting the city to ensure safe and sure realization of the project.

In addition to rising sea levels, Copenhagen is also plagued by intense rainfall. The city was particularly hard hit in July 2011, when many streets were flooded after a three-hour downpour. According to the Danish Meteorological Institute, weather events of this kind will become increasingly common, which was the reason for initiating the ‘Cloudburst Management Plan’. With the help of numerous modifications and new construction projects, Copenhagen wants to build a cloudburst infrastructure to combat the impending floods. Some 15 projects will be completed each year.

Blue-green infrastructure: In fine weather a lawn, in heavy rain a stormwater course.

The project is very complex due to the large number of parties involved and the close relationship between the individual engineering works. For this reason, Drees & Sommer climate experts were supporting the city with a review of the project and its cost structure. The consultants also closely examined risk management measures and the innovativeness of the concept. The focus was on the positive effects of the new infrastructure on the microclimate and on the overall energy balance of urban districts. “While adaptation to climate change is very costly, intelligent measures result in an overall enhancement of the urban habitat and thus represent a holistic economic solution. The project’s high level of innovation is also making Copenhagen a model for other cities worldwide,” says Christoph Küpferle, Director at Drees & Sommer.

The new blue-green infrastructure involves key public sector services: Mobility, public space, safety, and biodiversity. For example, during fine weather, green spaces will be available to the general public as parks, but in the event of heavy rainfall they will transform into lakes or stormwater courses and capture large amounts of water. Preservation of the quality of life is paramount, with esthetic aspects and convenience being taken into account in addition to functionality in an emergency. Several architectural firms are involved in the design, including Germany’s Ramboll Studio Dreiseitl. To minimize costs, some of subprojects are being combined with previously planned road redevelopment and upgrade works. The first measures are to be implemented in 2016.