Water Sensitive Urban Design (WSUD)
Introduction
WSUD represents a new paradigm in the planning and design of urban development that aims to minimise impacts on the natural water cycle and protect the health of aquatic ecosystems. WSUD promotes an approach to urban development that responds to a site’s natural features, protect natural ecosystems on site and downstream, and optimise the use of water as a precious resource. WSUD aims to deliver sustainable water cycle solutions in urban areas.
Additionally, WSUD aims to integrate these urban water cycle solutions into the planning and design of the layout (buildings and landscapes) of an urban development, towards an overall goal of ecologically sustainable development as shown below.
Relationship between water sensitive urban design, ecologically sustainable development and integrated water cycle management
What is WSUD?
WSUD seeks to minimise the negative impacts of urbanisation on the natural water balance. Urbanisation modifies the natural water balance by reducing infiltration and recharge of groundwater and increasing the export of large quantities of poor quality runoff into aquatic environments. Urbanisation also normally depends on the import of potable water from catchments beyond the footprint of the urban area and the export of wastewater into aquatic receiving environments. The WSUD water balance reduces the impact of urbanisation on the natural water balance by minimising potable water consumption and wastewater discharge, increasing infiltration and evapotranspiration, and improving the quality of runoff by treatment before discharge. These concepts are illustrated in the figure below.
The guiding principles of WSUD are to:
- Protect existing natural features and ecological processes;
- Maintain natural hydrologic behaviour of catchments;
- Protect water quality of surface and ground waters;
- Minimise demand on the reticulated water supply system;
- Minimise wastewater discharges to the natural environment; and
- Integrate water into the landscape to enhance visual, social, cultural and ecological values.
These guiding principles are being adopted in the Darwin region to reduce the impacts of urban development on receiving aquatic ecosystems, including Darwin Harbour. The principles are also consistent with the goals of the Darwin Harbour Regional Plan of Management.
