Like any other city located by the sea, Copenhagen will face particular threats as sea levels rise and heavy downpours hit the city with greater frequency and strength. The overall project is specifically designed to overcome cloudbursts previously understood to be extraordinary events ("100 year rain"), as well as a 30% increase in everyday rain.
Enlarging the sewer system would be an expensive solution, therefore the city opted for a natural rain infrastructure, such as green streets and pocket parks. However, this initiative will face three main challenges: securing funding, working in cooperation with stakeholders and engaging with neighbouring municipalities.
Copenhagen is taking a lead in addressing climate change by minimising its potential impacts, creating systems to deal with abnormal weather conditions and installing infrastructure to cope with damage, loss and traffic disruption.
Instead of choosing “grey” infrastructure as the main adaptation strategy (walls, barriers and underground tunnels), Copenhagen has opted for a city-wide layer of green climate adaptation solutions. If torrential rain hits the city, the integrated system of green streets and pocket parks will function as retention areas and water basins. Thanks to a new system, the squares will be able to collect water locally and direct it to the harbour. The infrastructure will also increase the city's resilience to the Urban Heat Island Effect as well as reduce the level of CO2 emissions.
Several projects have already been implemented, but the big construction projects are yet to come. The cloudburst plan was successfully tested through a pilot project in Skt. Kjelds neighbourhood. Here, the green surface solutions have prevented damage, loss and traffic disruption during recent heavy downpours. Other projects implemented have secured a large part of the city from damage during cloudbursts in recent years.
Copenhagen can expect an overall benefit from implementing the cloudburst strategy. The 300 projects it is pursuing will increase the level of flood protection across the city, while also taking urban planning projects, maintenance activities and resilience strategies into account.
Moreover, the green adaptation infrastructure will turn the city into a leader of sustainable solutions for the cities around the world, contributing to a greater green global economy.
The plan will bring important environmental and economic co-benefits. The long-term goals of the project are to improve water quality in the city’s harbour; to mitigate the Urban Heat Island Effect; to increase recreational opportunities for citizens; and to decrease air pollution. The plan is also a way to create growth, employment and a method of attracting new knowledge and businesses to the city.