1. FLOOD MAPPING Menaxhimi i rezikut te permbytjeve Objektivat Gjenerale

2. General Objectives 1.Protect people and goods 2.Preserve river capacity and flood plants 3.Conserve ecological equilibrium To reach these objectives, a regulation of land use in the floodplain is necessary: –Forbidding new construction in high risk areas, –Controlling urban extension in floodplain, –Limiting embankment to minimum.

3. Example of flood risk mapping Zone 1 - Little / no risk Zone 2 - Low to Medium risk (light blue) Zone 3 - High risk (dark blue)

4. Principe of flood risk analysis –Flood hazard assessment: three hydraulic parameters considered 1.Water depth, 2.Flow velocity, 3.Duration of inundation

5. Flood risks analysis Flood hazard classification Depth Velocity Low velocity (Plain flood) Medium velocity High Velocity (Flash flood) Depth < 0.5 mModerate Moderate to high 0.5m 1.0m ModerateHigh Depth >1.0mHigh

6. Flood risk assessment Vulnerability classification by distinguishing urban / non urban areas Flood risk mapping Flood plainUrban areas High flood hazardHigh risk Moderate flood hazard Low riskHigh risk  Flood hazard + vulnerability,  Vulnerability mapping

7. EXAMPLE Land use regulation Nature of time construction Type Non urban Zone Urban Zone Moderation hazard High flood hazard Habitation, Industries, activities NewXPrescriptionsX ReconstructionXXX ExtensionPrescriptions ModificationPrescriptions Public equipment All kindsPrescriptions Camping NewXXX ExtensionXXX Others NewXXX ExtensionXPrescriptionsX ModificationPrescriptions

8. Where are we now ?

9. Methodology Flood

10. Flood Hazard / Flood Risk Different scales –Preliminary flood risk assessment Drini River Basin –Local flood risk map Pilot area : Skenderaj

11. Preliminary flood risk assessment DATA GATHERING AND PROCESSING Topographical and hydrological data –SRTM 90 DEM –Contour lines (10m) –Historic floods etc. Problems and accuracy –SRTM DEM : 90m x 90m, dZ~10m –Shifting between different maps

13. DEM from contour lines SRTM DEM

14. Shifting between different maps

19. What are we going to do ?

20. Improving preliminary delineation of flood areas –Send questionnaires for the most sensitive towns –Process with available satellite imagery –For sensitive areas assess flood hazard with simplified hydraulic calculations and fields visits –Georeferencing all data

21. Remember past flooding events (2004-2008)

22. Skenderaj flooding zone

28. Local flood risk map Pilot area: Skenderaj  Work completed: Field visits Questionnaire prepared TOR for topographic survey  Next steps Hydraulic modelling Flood risk mapping Discussing about a pilot flood risk management plan

30. A quick presentation of the technology

31. Floodplain Mapping Approach Water surface profiles ArcGIS Geometric data Parameters Schematic Flow discharge Hydrology Hydraulic model ArcGIS HydraulicHydrology

32. Floodplain Mapping Approach ArcGIS Input Data DEM Hydrology Flood discharge Hydraulic Water surface profiles ArcGIS Flood plain maps Flow discharge Geometric data Parameters Schematic ArcGIS HydraulicHydrology

34. Digital Terrain Model: DTM ArcGIS HydraulicHydrology Observed points and break lines for constructing a triangular irregular network (TIN).

35. TIN components: - nodes - edges - triangles Triangular Irregular Network : TIN ArcGIS HydraulicHydrology DTM -

36. 3D display of a TIN. DTM – TIN 3 D display of topography ArcGIS HydraulicHydrology

37. DTM – TIN Display of buildings Embedding Buildings into the TIN. ArcGIS Hydraulic Hydrology

38. Topographic survey: Cross Sections Stream centerline. Banks. Flow paths. Cross sections. ArcGIS HydraulicHydrology

39. Hydraulic Modelling stream geometry. Cross-sections extracted from the TIN. ArcGIS HydraulicHydrology

40. Hydraulic Modelling Water surface elevations. ArcGIS HydraulicHydrology

41. Floodplain Mapping Floodplain ArcGIS HydraulicHydrology

42. Floodplain Mapping 2-D floodplain animation. ArcGIS HydraulicHydrology

43. Floodplain Mapping 3-D floodplain animation.