Case Study extracted from Salat, Serge. 2021. Integrated Guidelines for Sustainable Neighbourhood Design. Urban Morphology and Complex Systems Institute 2021. © UMCSII.

Stockholm is at the forefront of eco-neighbourhood progress. In 1996, the City decided to redevelop the 160-ha area (40 ha water excluded) of Hammarby Sjöstad in the south-east of Stockholm as part of its bid for the 2004 Olympic Games. Hammarby was a former highly polluted industrial and port area. The project targeted housing more than 25,000 inhabitants in 11,000 apartments by 2017. The objective was to create a neighbourhood with half the environmental impact of other districts built in the 1990s. Hammarby Sjöstad implemented an integrated approach that incorporates human-scale design, sustainable resource use, ecology, and low-carbon transport. Its strong environmental goals shaped the integrated plan, which covers land use, urban form, transport, building materials, energy, water, and sewage. Articulated density, access to multiple modes of transit, an emphasis on reduced car commuting, preservation and restoration of existing natural systems, and progressive construction and housing policies make Hammarby Sjöstad an effective demonstration of comprehensive planning. Through the city’s forethought in land acquisition, the planning department could efficiently coordinate mobility, land use, and development.

Key partners and actors

The planning and design of Hammarby-Sjöstad was made easier because the City had acquired most of the land. The local authority took leadership at every stage from development of the master plan to construction, spurred on by the City’s sustainability programme. Since all planning applications in Stockholm are based on life-cycle cost analysis, it was easier for the development to justify higher initial investments in better performing building design and transportation infrastructure.

The first step in the planning process was the development of the strategic master plan, led by architect Jan Inghe-Hagström, at the Stockholm City Planning Bureau. The plan is divided into 12 sub-neighbourhoods, which are being developed in phases. A process called ‘parallel sketches’ is being used in which the City selects three to four architects/planners in the private sector to draw up detailed proposals for a sub-neighbourhood. The city evaluates each of the sketches and combines the best features to create the master plan.

To provide architectural diversity, and to inspire higher standards of design through competition, a consortium of developers and architects are then invited by the City. They develop each plot or building within the sub-neighbourhood, according to the design code. Over 30 different developers and more than 30 architects have been identified. Key developers are JM, Skanska, Family Housing, Swedish Housing, HSB, SKB and Borätt.

Development and financing strategies

The first step in planning was the strategic master plan, led by architect Jan Inghe-Hagström, at the Stockholm City Planning Bureau. The plan is divided into 12 sub-neighbourhoods built in phases. In a process called ‘parallel sketches’ the city selected three to four private sector architects/planners to draw up detailed proposals for each sub-neighbourhood. The city evaluated each of the schemes and combined the best features to create a master plan. The city planning and design team then prepared a design code for each sub-neighbourhood in partnership with the developers and architects. The local authority used the design code to grant planning permission. The code provided an overview of the layout, form, and structure of each block, with key landmarks, public spaces, and pedestrian routes.

To foster variety, and inspire higher standards of design through competition, a consortium of developers and architects were invited to design each plot or building inside the sub-neighbourhood, according to the code. More than 60 developers and 30 architects were involved in the process (Foletta, 2011). The project achieved a high level of diversity and complexity within a coherent master plan. The city of Stockholm joined forces with twenty-five construction companies to construct the neighbourhood, with the latter contributing 80% of local cost. Another financing approach comes from two government agencies – the Swedish Rail Administration (rail transport) and the Swedish Road Administration (routing of the Southern Link ring road). Several features ensured an efficient development process with a good balance between planning and market. 

1. Single ownership: Almost the entire site was in a single proprietorship from the start. This meant that no competing interest unsettled the plan. 

2. Long-term vision of the master plan. 

3. Massive early infrastructure: Major public funding was key to delivery – with power, water, recycling – all put in place initially. 

4. Collaborative method: Developers and architects looked at how they could achieve a workable solution for each development area. Many different developers produced each zone with variations and changes to the design, while remaining under the same wider master plan. 

5. Clear delivery mechanisms: Developers had to pay for each site on a per-square-meter-of – development basis. This narrowed down the range of bidding, because of the restrictions enforced by the master plan – enabling a greater focus on the design to meet end-user needs. 

6. Flexible mix of uses: The master plan envisaged a blend of non-residential uses but didn’t impose constraints on them. Ground floor areas in certain key frontage zones had to be active, while being flexible for the end tenant.

Planning and design features

The integration of transport and land-use planning enhanced the project sustainability. The district spine is a 37.5-meter wide boulevard and transit corridor, which connects key transport nodes and public landmarks. It creates a natural concentration for activity and commerce. Arrangement of infrastructure was essential to connect the neighbourhood to the existing Stockholm networks. A comprehensive movement network includes trams, bike lanes, ferry links and pedestrian routes. It was put in place before development. Alongside this, the provision of a carpool with a priority parking has reduced car dependency. These policies and design measures have proven effective and are aligned with the common vision for green and thriving neighbourhoods. Transport-related emissions for inhabitants of Hammarby Sjöstad are less than half those of an average Stockholm citizen. They are less than a third those on average in Sweden. In 2007, 79% of Hammarby Sjöstad residents walked, cycled or used public transport for commuting (Iverot and Brandt 2011).

From an architectural point of view, an Innovative Green and Open Inner-City Block Typology is used. The subtle implementation of Stockholm urban morphology, sizing, and scaling establishes a unique place in Hammarby Sjöstad. The dense settlement structure comprises four- to five-story constructions around spacious green courtyards. The design follows Stockholm’s centre city morphology in terms of street width (18 metres), block size (70 × 100 metres), density, and land use. This human scaled urban fabric is integrated with openness, waterfront views, parks, and sunlight. The design allows for both wind-shielded and sunny inner quadrangles, with ample possibilities to develop inviting entrance and common courtyard greens and facilitate small-scale cultivation in micro-garden plots and greenhouses. The traditional Stockholm city fabric is transposed with a green architectural style. It responds to Hammarby Sjöstad’s waterside context.

It follows bioclimatic principles and maximises light and views of the water and green spaces. The integration of green and nature-based solutions is also part of the vision for Green and Thriving Neighbourhoods.

Compared with the closed blocks of the historic centre, the Hammarby types are open and discontinuous. This design allows more natural light to reach the courtyard-oriented parts of apartment buildings and optimises real estate values by maximising the number of lake views. The end outcome is an innovative urban green block between the traditional block model and a uniquely local and new type that offers larger floor plates and more exterior spaces.

Integration of neighbourhoods’ systems

The ‘Hammarby model’ is a unique eco-cycle system that seeks out opportunities to reuse energy, solid waste, water, and wastewater from homes, offices, and other structures in the area in an integrated manner. It is a balanced ‘closed-loop urban metabolism’. Among other strategies, the reuse of waste is particularly interesting. Indeed, the Hammarby model uses neighbourhood waste streams for generating energy and recovering heat. Energy is captured from three waste flows:

• The first burns combustible garbage to power a local district heating and electric plant.

• The second recovers heat from the sewage treatment system

• The third converts sludge to biogas for cooking (1000 units) and to power local buses.

The first step is diminishing the initial flow of waste. Hammarby Sjöstad set the goal of reducing solid waste by 15% by weight, and, further, has taken the most comprehensive approach by recycling or reclaiming all the remaining flows. Actions taken are:

• Use recycled materials where environmentally and economically feasible. 

• Deposit no more than 20% of construction waste in landfills.

• Sort and gather all solid waste (glass, plastic, metals, and paper) using a vacuum system at locations around the site, and recycle it. The system eliminates the transportation energy and pollution caused by garbage trucks. 

• Collect combustible waste and convert it into district heating and electricity. 

• Collect and compost garbage (organic waste).

The energy supply goals are:

• Supply 50% of the energy demand on-site. 

• Supply district heating by a heat recovery plant using purified wastewater from the site 

• Provide district heating and electricity by a cogeneration plant that burns combustible waste from the site, with additional biofuels obtained off-site.

• Incorporate limited arrays of solar photovoltaic cells and solar hot-water panels to demonstrate and test new technology.

• Generate biogas from wastewater sludge for city vehicles.

These solutions are well aligned with the common vision for Green and Thriving Neighbourhoods, indicating the pressing need to move to net zero emissions neighbourhoods via clean construction and green buildings. 

Lessons Learnt

The Hammarby-Sjöstad regeneration case study provides an example of how to redevelop and create value in dismissed areas within cities. The municipality holistic approach follows sustainable city planning principles with compact areas of medium-sized city blocks. The transit-oriented development approach, together with the integration of the neighbourhood’s systems, allowed the city to regenerate the former industrial area into a new vibrant settlement. To achieve architectural coherence and a high level of complexity and diversity, a participatory method that involves all stakeholders in the process was required. Ultimately, the design code elaborated by the municipality, conceived upon the principles detailed above, provides a general framework within which design proposals can be placed and coherently related to one another. Hammarby Sjöstad is an example of the design strategies presented in the guidelines in several aspects, featuring a comprehensive approach to neighbourhoods’ design.

References

Foletta, N. 2011. Hammarby Sjöstad, Stockholm, Sweden in Europe’s Vibrant New Low Car(bon) Communities. ITDP Europe.

Iverot, S. P., & Brandt, N. 2011. ‘The development of a sustainable urban district in Hammarby Sjöstad, Stockholm, Sweden’ in Environment, Development and Sustainability, 13(6), 1043–1064.