Water management system
5.2 Bench marking study - Melbourne water management
Sewage system
Water supply system Treatment system
Collection and transportation
of waste water Purification of
waste water Production Distribution
Groundwater
Surfacewater Precipitation
Drainage Leakage
Monitoring of water quality Monitoring of water quality
Drinking Water Company
City West Water, South East Water, Yarra Valley Water Water authority Melbourne Water Board
Recycle wa-ter system Stormwater
system
Sewer pipes Trunk sewers
Fig.24 Water management system in Melbourne
Wastewater
Fig.25 Relationship between water quality and urban demands
cities in the world that harvest water from protected catchments. Then water flows to storage places which is called reservoirs with some limited human activities. Finally water is extracted by water companies to make sure that is clean and safe for drinking. And they transfer the water to homes and business. Different from Eindhoven, part of the sewage system are in the charge of water companies. When the sewage flows to larger sewers, Melbourne water board are responsible to those pipes which is called trunk sewers.
However, what makes Melbourne water management system so unique and successful to achieve sustainable goals are recycle water management system and stormwater management system. Recycled water is used for a range of non-drinking purpose and is one of the ways to improve the resilience of water supply system.
Water board is the wholesaler producer of recycled water, supplying to the retail water companies. Actually, Melbourne water board proposed a concept called “ fit-for-purpose”, which means alternative sourcing of water should be linked to water use. As it is shown in
the diagram, this is a very cost-effective and sustainable approach, since the closer the match in terms of source of quality and quality required by demand, the less treatment is required in overall system. (Fig.25)
Before the explanation of Melbourne’s stormwater management strategies, WSUD (water sensitive urban design) principles should be stated here, which is adopted by Melbourne Water. In relation to “water sensitive cities”, a recent definition is: “a water sensitive city is a city which integrate water supply, sewerage, stormwater and built environment. A city that respects the value of urban waterways and a city whose citizens value water and the role it plays in sustaining the environment and society” ( Water Sensitive Cities Tour 2009). So the management and projects followed five principles below:
(1). Protect natural system: protect and enhance natural water system within urban developments.
(2). Protect water quality: protect the quality of water draining from urban development
Fig.26 A water sensitive city scheme Green roofs
Insulate buildings slow runoff and remove pollutants
Water harvesting and re-use Harvested rain water and stormwater can supply many of our water needs
Water play
Harvested water can provide opportunities for water features in public parks and activity centers
Wetland and rain gardens Slow down stormwater runoff and remove pollutant before excess run-off drains to water ways
Permeable surfaces Rain water infiltrates the soil for vegetation health and groundwater stores
(3). Integrate the stormwater treatment into the landscape: use stormwater treatment into the landscape by incorporating multiple use corridors that maximize the visual and recreational amenity of developments
(4). Reduce runoff and peak flows:
reduce peak flows from urban development by local detention measures and minimizing impervious areas
(5). Add value while minimizing development cost: minimize the drainage infrastructure cost of the development
The use of WSUD principles and tools allows it to restore and preserve the natural water cycle and to integrate with urban design and construction.
According to WSUD, some strategies have been proposed by Melbourne Water. First of all, they make rules for new developed projects. All of the new projects which area is more than two hectares must follow water sensitive urban design principles. The quantity of the streams should be controlled, the quality of the water should be protected.
Rainwater harvest is a compulsory approach added into developed site. And rainwater is regarded as an element of landscape, trying to emerge rainwater management into city landscape, combining function and aesthetic in a effective way. In the end, after rainwater harvest, reuse of rainwater is also a topic should be considered.
Melbourne water board is also a good organizer to facilitate the collaboration between different institutions. The water board not only work with the local government, but also work with business groups and stakeholders. For example, for Melbourne Water, a key part of the move to encourage a range of organizations to take up sustainable stormwater management, has been ensure the provision of a wide range of relevant training and education programs. The training program is called
‘Clean water” which is funded by water board in 2006. “Clean water” is now housed in Melbourne Water’s office, operating an information exchange and also developing training and education for industry or local government to help deliver best practice stormwater management and water sensitive
Fig. 29 Rain garden in a park in Melbourne
Fig. 30 Educational and collective rain garden
Fig. 31 Rain garden and new public space
Fig. 32 Rain garden and new public space Fig. 28 “Cloud shape structure” rain gardens scheme
“The design represents the three states of water as well as the water cycles, encouraging visitors to consider Fig. 27 “MUSIC” rain water
caculator
Melbourne
Water sensitive city In Melbourne, water management is integrated in design and strategies, and in the meantime, water landscappe and stormwater management are combined together in design. A lot of rain gardens are built here. These raingardens are not only technical tools for water management, but also several different public spaces, such as educational, meeting or recreational spaces etc.
urban design. A computer model called MUSIC ( Model for Urban Stormwater Improvement Conceptualization ) is used, which is a conceptual design tool that estimate both stormwater pollutant generation and the performance of stormwater treatment measures (Fig.27). Working with universities and other research institutions is another key part of Melbourne Water’s approach to sustainable stormwater management.
Water management is not only the issue related to government and companies, but also a topic related to every citizen’s life. The water board try to encourage public participation, involve relevant stakeholders and even provide support for community groups. They provided a platform on the internet which is called Storm calculator. It is designed very user friendly and could be used by general public. Typical users will be consultants, developers, architects, builders and local government staff.
STORM is used to assess whether best practice water quality objectives have been achieved for your site.
Furthermore, through education and incentive programs, water board encourage the community to install rain gardens and other filtration and reuse
options.
Actually, rain garden is the most efficient way to move towards water sensitive city. Rain gardens are one example of the range of biofilter systems that have been widely implemented in the last few years as a source control technique to manage stormwater runoff in urban areas (Le Coustumer et al 2009). As the University of Melbourne has noted:
“the solution to protecting creeks from the ravages of stormwater runoff is to retain as much of it as possible in the catchment to allow it to filter through the soils, to get to the creek slowly, to provide a more natural, clean base flow. Rain gardens are the perfect tools for achieving this.” (University of Melbourne, 2009). So from 2008 to 2013, Melbourne Water proposed to build community and local government capacity by providing support for the construction of 10,000 rain gardens across Melbourne (Fig.28-32). Part of this program involves working with local governments to ensure rain gardens are installed with regular street upgrades. The main objective of this 10,000 Rain gardens program is to inspire collaboration and community involvement in simple stormwater management measures.
C
omparing with these two water management system mentioned above, some aspects need to be improved in Eindhoven’ s water system.Eindhoven now still has the traditional water management system. There is no enough attention on stormwater and recycle water management which can be integrated into water sensitive urban design. However, in Melbourne, the diagram shows the obvious difference, they have these two kinds of management systems. And it is really an effective approach to optimize the whole system even to achieve sustainable and livable goals. To sum up, water sensitive urban design and integrated water management can tackle the challenges that Eindhoven face. Strategies, designs and infrastructure constructions should be combined together to fix the water issue problems in Eindhoven in the future.