Green and blue climate corridor in Kamen: A corridor for climate protection and adaptation to the impacts of climate change

Natural watercourses can act as communal climate control systems. By ecologically restoring the Heerener Mühlbach in Kamen, the Lippeverband water association created a “green and blue climate corridor.” Numerous measures ensure an improved natural water management, micro-climate, biodiversity and an increased quality of life in the immediate vicinity for the inhabitants.

Until recently, the Heerener Mühlbach was deemed by the EU Water Framework Directive to be a “heavily modified water body”, which meant that it was in poor condition with negative environmental and social effects. The natural aquatic ecosystem was only barely still in existence. In extreme summer heat, the stream dried up and its cooling effect evaporated, while under heavy rains, the risk of flooding was significantly increased. Citizens largely avoided the stream, and direct access was prevented through fencing for safety reasons.

Engine for progress:

  • Pioneer project for renaturalisation with adaptation to the impacts of climate change
  • Reduced hazards caused by heavy precipitation
  • Improved micro-climate
  • The body of water has been re-integrated into residents’ lives

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Heerener Mühlbach before: not much of a functional ecosystem remained here ...

The new green-blue climate corridor in Kamen

During the ecological restoration concluding in 2013, over a distance of two kilometres along the Mühlbach stream, the concrete bed was removed and near-natural banks were laid. This ecological restoration slows down the water drainage, strengthens the decentralised retention of precipitation and increases seepage. At the same time, with about 80 private properties in an area measuring 11,000 square metres of roofs and paved surfaces, the rainwater was separated from the sewage system. All this reduces the risk of flooding posed by heavy precipitation. As a result of the water and plant combination which has been established, there is now a green and blue corridor which benefits all sides – the climate, the town and the people.

For optimised climate and flood protection

The direct diversion of the rainwater from the properties into the course of the stream leads to a more even flow of water here. The danger of backflooding from the canal network is also reduced, thanks to the lowered intake of rainwater. Through the vegetation, the new course of the stream helps absorb CO2 and counteracts a further heating of the water, desiccation and the generation of heat islands in the town.

For enhanced quality of life and lower costs

Moreover, the renaturalised body of water – with the addition of a new walking and cycling path – also improves the living environment and quality of life for the residents, who were intensively involved in the restoration process. They also benefit financially: on the one hand, through the avoidance of flooding damages, on the other hand, through lower sewerage charges. All these factors combined also increase the value of adjacent plots.

Significant role model for adaptation to the impacts of climate change

In addition, the Kamen “green and blue climate corridor” project performed important pioneering work. At the start of the project, the link between river renaturalisation and issues concerning adaptation to the impacts of climate change was still very new, so the project enabled easily transferable ideas and practical experience to be gathered.

Photo: Lippeverband

“When ‘adaptation to the foreseeable impacts of climate change’ was initially discussed in 2007, it was not clear what this could mean. Larger drainage channels or higher dikes could not have been the right solutions even for climate protection reasons. The development of "no-regret” measures was something totally new: measures which have positive effects on our urban districts while conserving resources and at reasonable costs, irrespective of the actual scale of the impacts of climate change.

Applying this principle at Heerener Mühlbach in Kamen with the practical participation of the residents raised the citizens’ awareness of the impacts of climate change. They found out how they could themselves contribute to adapting to the impacts of climate change. The passive expectation of all-round protection provided by the public services was transformed into an active role enabling them to contribute something themselves.”

Dr Uli Paetzel, Emschergenossenschaft/ Lippeverband Chairman

Partners and sponsors

  • Lippeverband
  • Stadt Kamen
  • EU-Förderung

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