Kallang Riverside Master Plan
Landscape Architect : Wraight + Associates
Architecture : Woodhead
Engineering: Tony Wong Strategies; E2 Design Lab
Client : Singapore Urban Development Authority
Project Status: Competition 2012
Wā led one of four international teams shortlisted to submit a landscape and hydrological master plan for this significant 25ha+ development that flanks the Singapore CBD. The entry proposed a unique, holistic typology of high-density, water sensitive living. Water management was integrated at every scale amongst a settlement pattern that closely considered diverse social needs and existing site conditions.
This design offered a fully integrated ecological urban system, in which landscape and hydrology defined the urban form. Water flow through the precinct was to be made visible and, once filtered, would also be accessible.
The broad parks proposed would support new tributary streams that convey water collected in the built environment to the wetlands and on to the rivers. Runoff would thus be treated within the development before discharge into the river. The river reservoir is effectively storage, providing a major freshwater resource for the development. Water was proposed to be extracted from the river during dry weather periods, treated in the proposed stormwater treatment wetlands, and reticulated as an alternative water source for toilet flushing and irrigation of green building infrastructure, with overflow to feed back into the river.
The stream tributaries were proposed to be crafted with interactive elements that would also facilitate play. The existing statuesque trees formed the initial backbone of the planting in the tributary parks. New planting of native swamp forest species was overlaid. The tributary stream, large scale trees, lush native plantings with integrated passive and active recreation were to be key features of the parks to provide a particular identity to the precinct.
The conceptual drainage system for this site was guided by the site conditions and the unique opportunities provided by its location. The coincidence of drainage lines and mature trees influenced our decision to maintain a passive water supply for these trees while optimising the benefit of trees in terms of landscape and aesthetics, microclimate and heat island management, and stormwater treatment and flow management. The design incorporated elements of conventional drainage with WSUD elements such as bioretention systems and constructed wetlands. Our site analysis identified wetlands as a desirable option because of the overall hydrological conditions: space outside the development envelope, opportunity for river water harvest and treatment via wetlands during the inter-event period, and the river as a major resource of freshwater.