Applying Hazard Maps to Urban Planning

Transcription

1 Applying Hazard Maps to Urban Planning September 10th, 2014 SAKAI Yuko Disaster Management Expert JICA Study Team for the Metro Cebu Roadmap Study on the Sustainable Urban Development 1

2 Contents 1. Outline of Metro Cebu Roadmap Study 2. Development of GIS Database 3. Methodology of Development Suitability Analysis 4. Preparation of Thematic Maps 5. Overlay Analysis 6. Necessary Actions 2

3 1.1 Roadmap Toward The Vision Vision Roadmap 1. Metropolitan Development Framework 2. Roadmap Development Plans 3. Short-term Priority Projects 3

4 1.2 Objectives of the Study 1. To draw up a roadmap and detailed action plans based on Mega Cebu Vision 2050 with timeframework of: Short-term (2016), Med-term (2020), and Long term (up to 2030 up to 2050) 2. To formulate priority projects in association with institutional and organizational options for the materialization 4

5 1.3 Study Area The study area covers Metro Cebu consisting of 13 LGUs : 7 cities (Cebu, Danao, Mandaue, Lapu-Lapu, Talisay, Naga and Carcar) and 6 municipalities (Compostela, Liloan, Consolacion, Cordova, Minglanilla and San Fernando). Danao, San Fernando and Carcar are new comers to the old Metro Cebu boundary Metro Cebu 72 km 5

6 Municipalities Cities 1.4 DEMOGRAPHIC FRAME LGUs Land Area (km 2 ) Population Population Growth Rate (%/year) Cebu , , , Lapu-Lapu , , , Mandaue , , , Talisay , , , Danao , , , Carcar , , , Naga ,189 96, , Compostela 54 31,446 39,167 42, Consolacion ,296 87, , Cordova 17 34,032 45,066 50, Liloan 46 64,970 92, , Minglanilla 66 77, , , San Fernando 69 48,235 54,932 60, Metro Cebu 1,163 1,930,096 2,314,897 2,551, Source: PS Philippines 343,448 76,506,928 88,566,732 92,337,

7 2. TECHNICAL 1.5 Roadmap APPROACHES Development Plans 4 Strategies 7 Sub-roadmaps Competitiveness 1 Metropolitan Competitiveness Enhancement 2 Urban Structure and Land Use Mobility Livability Metropolitan Management 3 Urban Transport and Highway Network 4 Water Supply and Disposal Management 5 Solid Waste Management 6 Smart SRP Development 7 Metropolitan Administration An Overall Roadmap integrating 7 sub-roadmaps 7

8 Phase Work Plan of Phase 1 Schedule Work Items Participatory Activity 11 I-1. Preparatory Works 12 I-2. Analysis of Existing Conditions and Issues 2014/1 2 I-3. Conceptual Roadmap towards 2030 and 2050 I-4. Preparation of Shortterm Priority Projects I-5. Conduct of Home Interview Survey 1 st Seminar 3 I-6. Finalization of Phase I Activities 1 st Workshop

9 Phase Work Plan of Phase 2 Schedule Work Items Training 4 II-1. Development Frameworks for Sub-roadmap Planning Works 5 6 II-2. Metropolitan Competitivenes s II-3 Urban Spatial Planning II-4 Urban Transport Network II-5. Water Supply and Disposal Management II-6 Solid Waste Management 1 st Training in Japan 7 II-7. Intermediate Wrap-up of Roadmap Works 8 9 II-8. Sub-roadmap for Smart SRP Development II-9. Sub-roadmap for Metropolitan Administration 2 nd Workshop /1 II-10. Overall Evaluation of Mega Cebu Roadmap II-11. Finalization of Phase II Activities Comments from the Philippine Side 2 nd Training in Japan 2 nd Seminar 2/3 II-12. Study Finalization

10 2. Development of GIS Database Purchase of satellite image with resolution of 0.6m Preparation of Topographic Map in 1:10,000 based on the satellite image and LIDAR with the following specification Items Specification Attribute 1 Roads Center line, road edge line Name, Width (m) 2 Water River bank line, canal line, coastal line - 3 Contour 1m interval line in coastal area and 5m Height (m) interval line in the rest areas 4 Vegetation Polygon Type (agriculture, forest, shrub and pasture, vacant land, mangrove, wetland, sand, urbanized area, and others) 5 Building Footprint in polygon, smaller buildings in Name of public facility building 6 Public Facilities point Location and area of school, hospital, government office, fire station, police, church and park Name 10

11 3. Methodology of Development Suitability Analysis Topographic Maps and Data from Relevant Agencies 1 st Processing: Thematic Maps Slope Mountain Area Sea Level Rise Flood Landslide Earthquake 2 nd Processing: Overlay and Grid Analysis Land Use Constraints Natural Disaster Hazards 3 rd Processing: Grid Analysis Development Suitable Area 11

12 Thematic maps: Those are prepared using topographic map in 1:10,000 and data from relevant agencies. Overlay analysis: That is implemented to clarify the critical areas for development caused by constraints and natural disaster hazards. Grid analysis: That is implemented to accumulate the assessment scores of constraints and natural disaster hazards. Development suitable area shall be provided for future urban development. Those areas should be defined in urban planning map accurately. 12

13 4. Preparation of Thematic Maps and Hazard Maps 1) Existing Land Use 2) Slope and Mountain Areas 3) Sea-level Rise Hazard - 1m, 3m: Caused by Expected Climate Change by NAMRIA 4) Flood Hazard 5) Landslide Hazard 6) Earthquake Hazard 13

14 1) Existing Land Use 15% of Metro Cebu s land has been urbanized. 14

15 2) Slope and Mountain Areas Construction in steep slope area more than 18% is restricted. These areas and mountain areas are covering 72% of the Study Area. 15

16 3) Sea-level Rise 1m, 3m: Caused by expected climate change scenario, covering 0.04%, 0.3% of the Study Area 16

17 4) Geo-Hazard MGB provided the Geohazard map in 1:50,000 only because they are still compiling the results of field survey of 1:10,000 map. Therefore, JICA Study Team conducted hazard mapping using our GIS database and assessed flood and landslide hazards in 3 levels. 17

18 5) Flood Hazard Flood hazard level was assessed based on river flow simulation targeting 14 rivers of which river basin spreads more than 10km 2 and covered the expected flood scale over once a 50 years return period. Hazard Level Low (blue) Moderate (yellow) High (red) Definition Flood is expected to be occurred (Alluvial Plain) Sheet flood and drainage-caused flood Flash flood and road embankment-caused flood (possible to take a long flood duration) 18

19 5) Landslide Hazard Landslide hazard area was assessed based on interpretation of remotely sensed data from satellite image, digital terrain model (DTM) and contours. This work followed the MGB criteria for landslide susceptibility. Hazard Level Low Moderate High and Very High Typical Areas Slope gradients are below 18 degrees Slope gradients are degrees Steep to very steep slopes (>35 degrees) and evident active landslides, where inactive landslides are evident (old landslide debris deposits, collapsed sinkholes, old landslide complexes), actively worked mining areas, high erosion along the riverbanks 19

20 6) Earthquake Hazard Original maps comes from responsible agencies and digitized by JICA Study Team. Earthquake hazard will be assessed using grid analysis methodology which gives scores for each grid according to hazard level and accumulate the scores in same cell and reclassified. The grid size will be 250m x 250m. 20

21 5. Overlay Analysis 1) Existing Land Use and Hazard Map Urbanized area which is overlaid by hazard area amount to 1.9% of the Study Area. 21

22 2) Public Facilities and Hazard Map Location of public facilities can be assessed using hazard map by overlaying several layers. Those facilities located in hazardous areas should be prioritized for disaster resistant construction. 22

23 6. Necessary Actions Development Control System should be achieved by laws and enforcement system. Disaster Management Master Plan should be prepared based on risk assessment using detailed and accurate maps. It should include identification of shelters and emergency transport road network. Securement of Public Facilities should be implemented based on development of strategy for site and structural safety of public facilities, including existing facilities. Integrated Data Sharing System should be developed to share outputs of hazard maps and GIS analysis within government agencies and relevant organizations. It should be updated and maintenance periodically. Further assessment will be implemented in the following phase, applying population density and infrastructure & social service level indicators. At last, a future land use plan will be proposed. 23

24 Thank you 24