Land reclamation plan for Copenhagen

In 2019, the Danish government and the mayors of Greater Copenhagen announced plans to construct an artificial archipelago.

Since the 1990s, the population of Greater Copenhagen has grown from 1m to around 1.3m people and is predicted to rise by another 15 per cent in the next ten years. A large part of this expansion has been managed by transforming post-war industrial areas into residential housing.

This extensive construction activity is expected to produce 90m tonnes of surplus soil that will enable the creation of the artificial islets and natural protection of the existing coastline. It also makes the landscape resilient in the event of rising water levels in future, safeguarding the reclaimed land as well as the hinterland.

The land reclamation for Holmene offers the opportunity for innovative design rather than simply reverting to the landscape of the past. The advantages of the nine-islet design are that the project can be developed in stages without it looking unfinished, if, for instance, the economy slows into a recession and the demand for industrial sites decreases.

Furthermore, the islets can be developed thematically, each one offering the best conditions for a different purpose, such as innovative industry and research into green technology, biotechnology and life sciences as well as sectors that may emerge in future.

The potential for placemaking lies in the waterside location. Each island will have a green belt comprising wild and natural parks, with attractive transitions between land and water as well as interconnected bike paths. The diverse landscape will blend marshland, dunes, groves and scrubland, with sports and other activities taking place in some areas and recreation and nature walks in others. There are even several tiny islets and reefs, inaccessible to humans, that will provide the best conditions for nature and wildlife on land as well as in the water, to encourage biodiversity.

An essential part of the land reclamation is the green technology islet where the largest energy-generating waste-water treatment plant in northern Europe will be housed. Waste water from the region's 1.5m citizens will be processed here and turned into clean water, fertiliser and biogas mainly used for buses, household and industry. Biowaste collected from households and the industry can also be handled.

Together with heat storage, wind turbines and other green technologies, an annual reduction of at least 70,000 tonnes in carbon dioxide emissions and generation of more than 300,000MWh fossil-free energy is promised. This is equivalent to the electricity consumption of ten per cent of the population of Greater Copenhagen, and an important step towards the ambition for carbon neutrality in the city.

While the Holmene project is now in the design stages, the necessary legislation will need to pass parliament this year, and an environmental impact assessment carried out covering issues such as the effect on sea current, marine biology, infrastructure, and its synergy with other nature reserves.

Construction should start in 2022, with the first islet due to be completed by 2028. The entire archipelago is expected to be completed in 2045 or later, depending on the demand for industrial land and production of surplus soil from building sites and infrastructural projects.

Arne Cermak Nielsen is an architect at URBAN POWER architecture+urbanism  acn@urbanpower.dk

Related competencies include: Energy and renewable resources, Spatial planning policy and infrastructure