Abstract:
This thesis explores radical protection strategies for extreme weather events in Christchurch based on future climate change predictions with a central focus on mitigating flood and improving water usage efficiency. Climate change is increasing the frequency of extreme weather events. Going forward Christchurch is expected to have more floods and droughts causing extensive damage to the city. Historically, Christchurch was essentially a swamp that was rich in bio-diversity, and floods were mitigated naturally by wetlands, but urban intensification have drained much of these wetlands to make room for new urban developments, in the process, polluting waterways and destroying natural habitats. To highlight the potential severity of the future flood and drought problems and to enable unconstrained thinking on possible solutions, the year 2061 was chosen as the time when a solution would be proposed. Christchurch’s population is estimated to reach 1.5 million by 2061. This means that there will be further increases in urban development and associated resource demands. The city will require ground breaking novel strategic planning to accommodate the increased population. Water systems will need to meet the 2061 demand, as well as to prepare for extreme weather events. This thesis proposes a radical solution involving “water resilient” strategies in Christchurch City based on in-depth investigations into the causes of flooding and drought. The solution aims to create an environment for people and natural habitats to coexist with intensified urban development to accommodate future population. Specifically, the design approach adopts and refines proven mechanisms from precedent successful projects, assessing how these mechanisms can work together, and proposes a Sponge City Concept and suggests an architectural frame work for implementation. It is proposed that in 2061, Christchurch become a city of urban wetlands interweaved with intensive human development. The wetlands will provide flood protection, mitigate the impact from climate change, and stabilize the local rain cycle. The natural environment will attract wildlife back into the city. Water will be reused and the wetlands will provided more than enough water for the whole city. By harnessing the power from the different wetland systems and intensive urban development Christchurch will become a giant water machine, transforming the city into a resilient Sponge City.