Southbank Bratislava - Development for a major mixed-use area (SK)

'Gardens on the Danube' Project is Awarded Second Place in Competition for Bratislava's Southbank

KCAP's design for a major urban extension of Bratislava on the south bank of the Danube river was awarded second place in an international competition organised by Penta Developments. Six international teams were shortlisted to compete in the second stage of the competition from 52 first round submissions. The other finalists included OMA, Bjarke Ingels Group, Zaha Hadid Architects William Matthews Associates + Mikhail Riches and the winner Snøhetta + Studio Egret West.

The project called for a 210,000 sqm mixed use development over 6.8 ha on three plots along the riverfront. KCAP's proposal integrated architectural, urban and landscape design to create a coherent and open city district that seamlessly connects to the existing city and the larger masterplan of the area. The project takes the opportunity to counter the trend of insular, fragmented developments with Bratislava that could be excellent architecturally but fail to engage with their urban context. KCAP took a different approach, establishing clear urban design guidelines to bring a coherence to the whole Southbank district.

Given its position at the river banks, adjacent to significant areas of biodiversity, the design team took the approach of merging city and nature to create a habitat in the city for all, fauna and flora included. The approach could be characterized by an integrated system thinking that prioritizes the inclusiveness of both water and nature, giving the district a strong identity as a neighbourhood integrated with the river landscape.

KCAP's partner, Jeroen Dirckx, commented: "Our design for Southbank is an innovative living and working environment where city and nature are not seen as opposites, but as a total system where they come together."

The urban design introduces an open block typology which creates a well-defined transition between public and private space and frames the streets and squares. The open structure pulls the landscape into the neighbourhood, establishing an ecological and recreational connection to the riverbank and adjacent green structure. The openness also allows for optimum sun exposure for all the residential buildings, meeting Bratislava's strict requirements for direct sunlight. The plan locates office buildings closer to the highway, helping shield the residential areas from noise and pollution. Clear height datums provide a consistent building levels across the plan and give an overall coherence to the urban form. The building volumes step up from the riverfront to 110m tall towers creating a new urban skyline for the city and providing views towards the river and historic centre. The section introduces layers of landscape to bring nature close to people on all levels of the plan and break down the overall scale of the development to make it more human and approachable.

The landscape and placemaking strategy is centred around water management and supporting biodiversity. Central to the scheme was the idea of working with the river and its natural cycles and flows in order to develop and ecologically sound and inherently contextual scheme. The tributaries and historic river landscape situation was used as a guide to create a riparian and alluvial forest landscape, strengthening the natural habitats of protected target species. The landscape within the dike is designed to be climate adaptive, collecting and buffering stormwater to infiltrate it in the aquifer. These integrated natural solutions go hand in hand with making a liveable and vibrant neighbourhood, fostering community building.

In the design of the buildings, KCAP's aim was to bring a diversity to the architectural expressions across the plan yet avoid an anything goes approach. Clear guidelines were established to ensure a certain amount of coherence within the individual expressions of building. Strong horizontality, which integrates shading and energy generation into the facades, was chosen as a commonality in the architecture as was the use of an earthy palette of light materials that were bio-based and circular in their nature. The integration of landscape as open levels in the towers is combined with pentagonal volumes to introduce a slenderness and play in the architectural forms. Work and meeting spaces are embedded in layers of landscape on terraces and connecting bridges to create a multi-level network of spaces supporting knowledge exchange and opening up a typically closed building type to the wider city.

Sustainability and environmentally conscious design is considered as an integral part of the plan. The project has the ambition to be completely electrified making it completely net-zero ready. The amount of renewable energy produced on-site is maximised through integrated energy production in the architecture and the landscape. The scheme is naturally adapted to climate change with extensive green areas help to combat the urban heat island effect, open blocks provide cross ventilation and buffering of storm water on green roofs and in the landscape help with drought tolerance. The project integrated circular design principles from the start. Cradle-to-Cradle processes will be used to ensure all materials are part of a holistic plan for re-use and re-cycling. The design goes beyond only thinking about the physical elements in the plan to encourage a sustainable and healthy lifestyle and help cut energy use in everyone's daily life. The dense, mixed use neighbourhood is designed for the pedestrian, encouraging people to shop, work and play locally. Electric mobility solutions are prioritized and public transport connections are optimally located to encourage their use in daily life.

KCAP developed several computational processes for the competition that aided in the design of highly sustainable, comfortable and socially engaging living environments. These data-driven methods are integrated into the design process in the form of algorithms that optimize the shape of the buildings to guarantee continuous sunlight into every apartment, going beyond the minimum requirements set by regulations. An additional computational process was also used to determine optimum floor plan angles to maximize the number of spaces with views to the river banks and historical landmarks.

While not selected to develop its scheme further, KCAP has been privileged to be part of the conversation as to what the Southbank can become. Jeroen Dirckx: "We congratulate the winning team of; Snøhetta, Studio Egret West and gro architekti, and wish them all success in implementing this ambitious and important project for the city of Bratislava."