Sustainable Urban Drainage Systems - Ecosystem Services beyond Flood Mitigation

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1 Sustainable Urban Drainage Systems - Ecosystem Services beyond Flood Mitigation Professor Tony Wong Chief Executive & Director Centre for Water Sensitive Cities Monash University

2 Effective Drainage & Flood Mitigation Future cities would incorporate into its urban planning and design of appropriate land uses in accordance to the three-tiered approach of retreat, adapt and defend against future flood vulnerability. A water sensitive city would establish a network of blue and green open spaces and corridors to serve as an integral element of the city s drainage infrastructure and floodway for flood conveyance during rare (low probability) storm occurrences. Linking Water Sensitive Urbanism to Urban Liveability

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4 Stormwater Quality

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7 Streetscape Lynbrook Boulevard 1999

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15 Saturated zone with carbon

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18 Clean & healthy water environment. Waterways are valued as an integral part of a liveable city, and its ecological integrity actively protected. Urban waterways in a water sensitive city are managed with the underpinning knowledge that healthy waterways provide important ecosystem services that make a city more liveable and mitigate the impact of the city on the environmental values of aquatic systems within and downstream of the city. Linking Water Sensitive Urbanism to Urban Liveability

19 Access to secured and clean water supply With the exception of temperature, predictions of future trends in climatic conditions, particularly seasonal rainfalls, remains highly uncertain. Future liveable cities would secure its water supply through investment in a diversity of water sources underpinned by a range of centralised and decentralised infrastructure providing cities with the flexibility to access a portfolio of water sources at optimal value and with least impact on rural and environmental water needs. Linking Water Sensitive Urbanism to Urban Liveability

20 Mitigating urban heat Climate responsive designs will have a positive effect on human health. Urban heat mitigating design responses should place particular emphasis on the strategic implementation of WSUD technologies and green infrastructure. Green infrastructure supported by such design principles of keeping water in the landscapes and promoting lush and well-irrigated vegetation can provide microclimate benefits by reducing excess urban heating (through shading, and cooling by evapotranspiration) and limit human exposure to extreme heat. Linking Water Sensitive Urbanism to Urban Liveability

21 Source: Ishida (1993)

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24 The quality of public spaces Urban water systems could be designed in urban environments to incorporate means of enhancing social engagement and cultural expression Public spaces to include the celebration of water in urban environments with art features that respond to water availability and seasonality, and the establishment of biodiversity terrestrial and aquatic corridors. Linking Water Sensitive Urbanism to Urban Liveability

25 Urban design strategy Parklands, green waterways, structures and buildings are green infrastructure that emphasise the important role that vegetation (and therefore water and irrigation) plays in urban environments. Access to alternative fit-for-purpose water sources provides an additional and abundant source of water to allow the greening of cities. Linking Water Sensitive Urbanism to Urban Liveability

26 The way we manage urban water influences almost every aspect of our urban environment and quality of life.

27 roadmap for urban water reform to support a more liveable, sustainable and productive city.

28 Water extremes & vulnerabilities Population growth & urban densities Key challenges to urban liveability Urban heat Degrading environments

29 Water Sensitive Urban Design for:- Access to secured and clean water supply Water Clean & healthy water environments extremes & Effective Drainage vulnerabilities & Flood Mitigation Mitigating urban heat Delivering quality public spaces Population growth & urban densities Urban heat Key urban water reform agenda A new economic valuation model Science-policy partnerships Degrading environments

30 Measuring the full impact of any (urban water) investment option.requires a shift to value-based decision making across both space and time.

31 Understanding The Enabling Context 1. Socio-political Capital 2. Bridging Organisations 3. Trusted & Reliable Science 4. Binding Targets 5. Accountability 6. Strategic Funding Points 7. Demonstration Projects & Training 8. Market Receptivity Designing the Stormwater Quality Management Framework for Singapore

32 Understanding The Enabling Context 1. Socio-political Capital 2. Bridging Organisations 3. Trusted & Reliable Science 4. Binding Targets 5. Accountability 6. Strategic Funding Points 7. Demonstration Projects & Training 8. Market Receptivity Designing the Stormwater Quality Management Framework for Singapore

33 ABC Waters Implementation Framework for Stormwater Management in Singapore Regulatory and Administrative Framework Technology Development & Implementation Building Industry Capacity Linked to broader sustainability policies Protection of Marina Reservoir Catchment Planning Policies Precinct & regional stormwater management plans Performance Targets Rating Tool & Compliance Validation Singapore Stormwater Quality Research Initiative Research & Development Field Experiments & Monitoring Local catchment characterisation Demonstration Projects Engagement with other professionals Design Guidelines & Standards Operation & Maintenance Technical Tours Training Tertiary Education 4. Binding Targets; 5. Accountability; 3. Trusted & Reliable Science 7. Demonstration Projects & Training 6. Strategic Funding Point; 8. Market Receptivity

34 SUDS transitioning to Ecological Landscapes Green Infrastructure for: drainage and flood mitigation a network of green and blue corridors for flood conveyance and fostering biodiversity in urban environments water quality improvement to protect and enhance ecological values of aquatic environments stormwater as a resource to build water supply resilience through diversity of sources buffering aquatic ecosystems from the effects of catchment urbanisation and climate change Influencing urban micro climates promoting climate responsive design in urban environments The changing role of Urban Landscapes

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