Candidate – Denmark
Submission by: City of Copenhagen
Project name: Karens Minde Axis
Link: https://www.kk.dk/brug-byen/byens-groenne-oaser/parker-og-groenne-omraader/karens-minde-aksen
Short description
Karens Minde Axis is a multifunctional cloudburst project in Copenhagen’s South Harbor that combines climate protection, urban space improvement with accessible new nature in a successful synthesis of function, aesthetics, sustainability, and community interests. The project spans a 600-meter green urban stretch that has been adapted and developed to handle 15,000 m³ of cloudburst water. Besides serving as a safeguard against future flooding, the project exemplifies the integration of cloudburst management with the development of urban spaces and nature. A central element is a yellow tile “riverbed” that winds between existing trees and functions both as a path and as an element to manage water flow while unifying an area that was previously divided. The water’s path can be seen in the riverbed’s design, and is directed over a percolation meadow where heavy particles are filtered out. The purified water ends up in a newly established rainwater reservoir.
Social cohesion
The municipality brought together a diversity of people in gender, age etc. from the community to be part of the development keeping the process of the design transparent. A goal was for both old and new residents in the area to know and use the place. Integrating cultural activities and social challenges in the cloudburst solution should strengthen the existing qualities around Karens Minde Culture House. As well as opening the building to the surroundings. The local ownership for both process and final result through dialogue, has been a driver for local actors to continue afterwards. The aim is keeping the spirit of the South Harbour District, while the area is in riveting development, so that the local community could still identify with what the architects introduce in the design for the place. To see that the wishes and needs have been listened to and integrated.
Biodiversity
The winding form of the cloudburst solution has ensured that most of the large trees in the area have been preserved. Around 70 new trees have been planted and native plants have been added – fruit bushes, apple trees, and butterfly bushes, herbs in the percolation meadow, as well as local herb-grass mix for the lawns. Local plants and greenery enhance the living conditions of insects, thereby increasing biodiversity.
The cloudburst solution introduces a wet basin and wetland for rainwater retention and purification. The permanent waterbody provides a new habitat for the area. The wetland is temporarily flooded and dry which provides a valuable habitat for new species. These two elements add diversity to the previous grass lawns.
Economic factors
The nature-based solution for climate adaptation is chosen on terms of being the most cost-effective solution compared to a traditional pipe-based solution for stormwater management. The economy for the entire project is combined of municipal tax for area renewal as well as water-tax. The cloudburst project is defined based on a socioeconomic calculation for a surrounding watershed consisting of approximately 10 projects.
More local inhabitants (from both ‘the old’ and ‘the new’ Sydhavnen) should know and use the area and the cultural possibilities. The Karens Minde Culture House library and café profits from the area now being a secure, green connection that offers great urban-nature experiences and more opportunities in everyday life, activities, cultural events, experiences and community. The place has become an attraction for the whole city and for international visitors.
The impact on the climate
The project holds capacity for 15.000 m3 of rainwater from the surrounding catchment. The volume is calculated based on the expected climate changes in a hundred-year perspective. The effects of climate change in the area are defined and described in the city-wide climate adaptation and cloudburst plan for Copenhagen. In addition to cloudburst management, the project receives everyday rain from roofs and surfaces of adjacent buildings around the park, whereas the number of overflows from the sewer system into natural waterbodies is reduced.
Evaporation from the pond and wetland has a cooling effect in warm and dry seasons. The new paths make it more attractive to seek shadow under the canopies of the mature trees. The light color of the tiles has an albedo effect reflecting the sun compared to a dark color such as asphalt that would heat up.
The contribution to the well-being of visitors/users
As a visitor you feel invited into the area to spend time in the green surroundings, that provides shade for warm seasons, serenity in a busy city life and meeting places for people seek to get out of the loneliness of their homes. By removing fences, the project has removed barriers of both physical, cultural and social character. The goal is ‘Copenhagen Together’ – sharing the city, and to create space for people to meet across of social and cultural divisions.
The green is made more accessible. A pond can be experienced at close hand, where the area before was inaccessible shrubs and mud. A formal path is now a more universal design, accessible for wheelchairs and other. A road for car access has been diverted, and visitors can more safely move around in the area by foot. Rearranging the place for the existing ‘dog park’ made space for a path all the way through the northern park.
The selection, origin and quality of used products and materials (greenery and constructing materials)
One aim of the project has been to add and subtract as little as possible creating a subtle landscape project that does not feel alien/out of place, building on the identity of the area. The South Harbour is known for being a bit unpolished and “wilder” while bringing you close to nature. The project builds upon this identity by, for example embracing a rougher and wilder expression, while also using “natural” materials such as wood and bricks in a colour palette that reflects the area’s 1950s yellow brick buildings.
The project also supports and enhances the existing nature in the area – great value has been put on preserving areas with special natural value, such as a small pond with amphibians. Also exiting greenery, plants and the large old trees have been preserved and adapted to the new project – e.g. by lifting the crowns of the trees through pruning to create visibility and coherence in the park. On the slopes of the new rainwater reservoir native trees, bushes and grasses were planted while varying sized rocks and stones were installed to help create habitats for insects, small animals and amphibians. The few individual felled trees were reused as thickets and insect hotels, as well as agility equipment in the new dog park. The area around the rainwater reservoir is free of benches and artificial lightning to avoid disturbing wildlife.
The yellow brick tiles at the heart of the construction are inspired by the many existing yellow brick buildings and brickworks in South Harbor. The tiles are from Germany as Danish bricks are porous and not suitable for paving.
The overall design (landscape and optional associated buildings)
The large tree canopies in the area, and the organically shaped yellow riverbed, create a space where the existing trees act as a natural roof over visitors, providing a safe, pleasant, and sensory space to move through. At the same time, the yellow color and fine materiality of the bricks are highlighted – inspired by the many brickworks in the area. The overall design concept allows the project the serve both as a path, a watercourse, and a new, safe and welcoming green urban space.
The overall design element, and the central element of the project, is a beautiful yellow brick-paved “riverbed” that winds its way in and out between the site’s existing, large trees of the green park. The path of the water is traced in the riverbed’s highly organic longitudinal and cross-sectional profiles, and the riverbed functions both as a path and a water-directing element. The water gathers in a central marked channel and flows down through the landscape over a percolation meadow, where it is filtered for heavy particles, eventually ending in a newly established rainwater reservoir/pond. In this way the overall design element: “the yellow riverbed” constitutes a watercourse that literally connects an area that was previously very divided.
A new activity area, an “extension” of the yellow tile riverbed, ties the space together surrounding the Karens Minde Cultural Center, creating greater cohesion in the areas surrounding the cultural center, the dance pavilion and other buildings located here. Now, accessibility to and visibility of the cultural center has been significantly improved, and life is enjoyed in good weather, and playful souls delight in the flow of water when the rain takes over, filling the water channels and streams.
The impact on the environment (holistic, circular approach)
The aim has been to use existing qualities of the area to create a solution leading cloudburst water through the city in a sensible way. A cloudburst solution where water flows on the surface, rather than underground, saves resources in materials, labour, transport and reduces CO2 emissions. The project follows the ‘design for assembly’ principle, as all bricks can be reused. The yellow riverbed winds in and out between the existing trees to ensure their preservation. While a straighter cloudburst solution with deeper water channels would have been easier to create, it would also have required the felling of trees and damaging of the root system of many trees.
Biodiversity is enhanced through the percolation meadow, the new rainwater pond, shrub and bulb plantings, and the trunks from the few trees that were felled, which have been reused as insect hotels and agility equipment. With the new percolation meadow, the project creates a large natural “sponge” that filters and purifies the water before it flows into the new rainwater reservoir and is directed into the harbour. The already cleansed water relieves official wastewater treatment plants – reducing CO2-emmissions.
Socially the impact on the environment is interesting and life-giving as the residents have truly embraced the project. They now report being more satisfied with the area than before. This is partly the result of a very thorough community engagement process, which has given residents a strong sense of ownership. They actively use the area, which has become a significantly improved green gathering and meeting place. Additionally, the project has enhanced the conditions and facilities for animal care at the Children’s Animal Farm. Having animals nearby plays an important social and emotional role in children’s development.
The innovation value of the project
The project is innovative for several reasons. All the technical water management solutions have been transformed into architecture that aesthetically enhances the public spaces and green path systems. The water management solutions are integrated into the design of the yellow “riverbed”. An example is the spillways, where surface water from the surrounding streets, and from a large catchment area in Valby (north of the project) flows out onto the riverbed itself. The spillways have been shaped into large, soft forms that invite people to linger and play, becoming a part of the new, aesthetic urban space.
The innovation value is also evident in the project’s scale – Karens Minde Axis is a unique large-scale project where public spaces, landscapes and urban nature are developed alongside rain and stormwater management in a green urban park. Large volumes of rainwater – not only from the surrounding streets but also from a significant catchment area to the north of the axis – are managed within an existing urban area. The cohesive riverbed, which is the central element of the entire water management solution, connects and creates new pathways in a green area that was previously very fragmented, inaccessible, and in some places, unsafe to navigate.
Cleansing the water by directing it through a percolation meadow represents innovation, as nature-based treatment processes for rainwater purification are new – and according to monitoring, they perform on par with conventional rainwater systems and reservoirs. Additionally, the pumping solution adds value to innovation, as the design has not only minimized pumping requirements for surface water but has also turned it into a visible feature, positively contributing to residents’ experiences of the public space.