Green Urban design for Can Tho city: Where to start?

Transcription

1 GREEN DESIGNS FOR INTEGRATED URBAN WATER CYCLE MANAGEMENT SOLUTIONS FOR SECONDARY CITIES IN GLOBAL SOUTH TO COPE WITH CLIMATE CHANGE Can Tho city, 8 10th December, 2015 Green Urban design for Can Tho city: Where to start? Nguyen Hong Quan (IER, VNU HCM), William Veerbeek (UNESCO-IHE)

2 CONTENTS GREEN URBAN DESIGN WHERE TO START: WHAT? WHERE? WHEN? HOW?

3 1. GREEN URBAN DESIGN

4 1. GREEN URBAN DESIGN Water Sensitive Urban Design The integration of management of the urban water cycle with urban planning and design is known as Water Sensitive Urban Design (WSUD). WSUD has multiple environmental benefits including improving urban landscape, reducing pollutant export, retarding storm flows and reducing irrigation requirements (Melbourne Water, 2005)

5 1. GREEN URBAN DESIGN What is Green Infrastructure? The region s life support system; a network of natural environment components and green & blue spaces that lies within and between the cities, towns and villages, and which provides multiple social, economic and environmental benefits (P. Wilmer, 2007)

6 1. GREEN URBAN DESIGN (Lloyd S D. et al, 2002)

7 1. GREEN URBAN DESIGN Four major inter-related issues are identified as essential elements in advancing the concept of WSUD in Australia. These include (i) Regulatory Framework; (ii) Assessment & Costing; (iii) Technology & Design; and (iv) Community Acceptance and Governance (T. H. F. Wong, 2006)

8 1. GREEN URBAN DESIGN The implementation of WSUD can be enabled through the effective interplay between the two variables discussed below (Brown R., Clarke J., 2007)

9 1. GREEN URBAN DESIGN Longer concentration times More infiltration Re-greening: Planting trees Peak storage Macro-scale (Catchment, region) Benefits SUDS: Retention & detention areas Damage reduction Increase infiltration Damage reduction Increase infiltration Bad urban form: substantial urbanization in upper catchment Pressures Poor drainage: Insufficient pipe drainage capacity on neighborhood level Meso-scale (Neighbourhood, city) Benefits Flood proof building: Elevating homes Increased Surface Runoff Pressures Local Flooding Flood sensitive design: Even leveled access to shops (i.e. no doorsteps) Micro-scale Damages (Building, Road, etc.) (Zevenbergen et al, 2008)

10 1. GREEN URBAN DESIGN Scales of applications Building Scale (T. H. F. Wong, 2006)

11 1. GREEN URBAN DESIGN Various scales of stormwater bioretention systems recently constructed in Australia (T. H. F. Wong, 2006)

12 2. WHAT - TECHNIQUES

13 2. WHAT Adaptation options Rain water tank, Rain gardens/green roots Bio-retention Swales/basin Constructed Wet lands Pond.

14 2. WHAT WSUD: Restoring the normal water balance in the city

15 2. WHAT - TECHNIQUES Rain tank (Kim et al, 2012)

16 Small scale, Cottage roof Medium & Large scale, Concrete roof 2. WHAT - TECHNIQUES ( Phu, V.L, 2015)

17 2. WHAT - TECHNIQUES Constructed wetlands

18 2. WHAT - TECHNIQUES Green roofs/rain garden SNU, Korea Kindergarten, Vietnam

19 2. WHAT - TECHNIQUES Bio-filtration system 60% reduction in Total Suspended Solids (TSS) 47% reduction in Total Phosphorus (TP) 66% reduction in soluble phosphorus 29% reduction in soluble nitrogen

20 2. WHAT - TECHNIQUES Retention pond

21 3. WHERE

22 3. WHERE International Workshop for Practitioners Can Tho City, Viet Nam, July, 2014 Source: Summary report (Assela, 2014)

23 3. WHERE (Lloyd S. D. et al, 2002)

24 3. WHERE

25 3. WHERE Case-study areas (might) serve an important role in local flood mitigation as well as other water related pressures (e.g. quality). Furthermore, cases could provide additional benefits: liveability

26 3. WHERE Can we participate in the on-going Bun Xang project?

27 3. WHERE Can we participate in the on-going Bun Xang project? KẾT CẤU ÁO ĐƯỜNG KẾT CẤU VỈA HÈ

28 3. WHERE Can we participate in the on-going Bun Xang project?

29 3. WHERE Can we make use of big institutional space?

30 3. WHERE Interventions at household level?

31 3. WHERE Can something be done on Roads?

32 3. WHERE Multi-purpose public places Detention basin

33 3. WHERE Multi-purpose public places Detention basin

34 3. WHERE Other possible locations?

35 4. HOW

36 4. HOW HOW TO ADAPT MEASURES IN DEVELOPING COUNTRIES Ensure proper implementation According to specs; Complete instead of partial; Ensure operation Performance monitoring, reporting; Maintenance, budget, Organization, etc. Flexibility Future renewal, upgrading;

37 4. HOW How where successful projects acquired, arranged and executed in other countries? How was the involvement of the national, regional and local government? Which other local stakeholders were involved? Where there public-private partnerships developed? Was there a clear business-case? Where there innovative financing arrangements developed? How is operation, monitoring, maintenance and upgrading arranged? Was there involvement of donor organizations for financing? VINHOMES CENTRAL PARK

38 4. HOW

39 4. HOW Household Housing Project Public area Sewer Street flow Drainage system Retention basin Permeable land covers De-/Retention facility Retention facility Connectivity to retention pond 39 (Sources: Ho. L. P.)

40 5. WHEN

41 5. WHEN Measures IS IT TOO LATE? Dyke, sluice, pumping stations Green management Retention basin Dyke, sluice, pumping stations Improving drainage system Retrofitting Improving drainage system Retrofitting Improving drainage system Retrofitting Time, river levels, rainfall

42 Thank you for your attention

43 43 (Brown R., Clarke J., 2007)

44 44 (Brown R., Clarke J., 2007)

45 1. GREEN URBAN DESIGN Flood alleviation and water management BENEFIT VALUE Investment in Green Infrastructure Improvement in the quality of environment within urban and semi-urban locations Reduction in flood risk for highly populated areas Increase in Land and House Prices Reduction in Insurance Premiums Lower clean up costs for local and central government Encouragement of inward investment Increase in economic activity, jobs and growth Lower costs to Environment Agency of SUDS vs. Hard engineering solutions (P. Wilmer, 2007)

46 1. GREEN URBAN DESIGN Quality of Place BENEFIT VALUE Improved quality of life for residents Reduction in poor health Investment in Green Infrastructure Increased involvement of local communities in ownership and management Reduced maintenance costs through community ownership and management of green space Improved attractiveness of place for investment Increased house and land prices New employment opportunities from Inward Investment (P. Wilmer, 2007)

47 1. GREEN URBAN DESIGN Improved Health and Well Being BENEFIT VALUE Investment in Green Infrastructure New opportunities for formal and informal recreation Increase in local air quality - reduced ozone, CO 2 Reduction in obesity levels Reduction in stress related illness Reduction in Coronary Heart Disease and related illnesses Reduction in costs to the NHS and waiting lists Increase in economic activity and job productivity Reduction of illness associated with poor air quality e.g. Asthma (P. Wilmer, 2007)

48 1. GREEN URBAN DESIGN Land and property prices BENEFIT VALUE Higher demand for neighbourhoods with good access to green space Increase in House Prices Investment in Green Infrastructure Improved natural environments within urban and urban fringe locations Uplift in land values Improvement to the public realm and urban design New employment opportunities (P. Wilmer, 2007)

49 1. GREEN URBAN DESIGN Creating a setting for inward investment BENEFIT VALUE Improved quality of life and environment, encouraging property developers and investors. Increased Land/ Property Prices Investment in Green Infrastructure Revitalisation of DUN land on permanent and temporary basis Growth in the occupancy of vacant units within Market Towns/Key Service Centres Green Business Parks attracting knowledge economy businesses Increase in economic activity (P. Wilmer, 2007)

50 1. GREEN URBAN DESIGN Tourism, recreation and leisure BENEFIT VALUE Increased numbers of people accessing new woodlands and greenspace for new recreation opportunities Safeguarding and creating jobs for those employed in Tourism sector Investment in Green Infrastructure Growth in Natural Tourism New urban employment from new visitor economy Green Cities - more attractive to investors and visitors Increased economic output through Natural Tourism (P. Wilmer, 2007)

51 1. GREEN URBAN DESIGN Land management and biodiversity BENEFIT VALUE Growth in rural diversification opportunities for the Land Based Sector Safeguarding and creating jobs for those employed in the Landbased sector Investment in Green Infrastructure Improved management of the countryside through Stewardship Schemes Increased economic growth through local procurement for agricultural sector Increased economic output through Natural Tourism and Niche Markets (P. Wilmer, 2007)

52 1. GREEN URBAN DESIGN Climate change alleviation BENEFIT VALUE Investment in Green Infrastructure Providing Adaption - microclimate control - water management Enabling Mitigation - carbon sink - carbon sequestration - O 2 production Improved Local Air Quality Reduced Carbon Emissions Local Energy Solutions Reduced costs to industry and households Delivering Climate Change Levy Targets (P. Wilmer, 2007)

53 1. GREEN URBAN DESIGN Different urban typologies for the same density (75 units/ ha) (W. Veerbeek, 2014)