Overview of HAZUS Flood Loss Estimation Model

1. Overview of HAZUS Flood Loss Estimation Model The HAZUS Flood Model is being developed for FEMA under contract with the National Institute of Building Sciences (NIBS). EQE International and project partner Michael Baker Jr. Inc. are the flood model subcontractors to NIBS. The flood model has an oversight committee composed of floodplain management practitioners from across the nation. NIBS has also created a software oversight committee to help guide the integration of the three loss estimation tools (Earthquake, Wind, and Flood). The Flood and a preview version of the Wind model will be incorporated with the earthquake model in HAZUS03 scheduled for release near the end of 2002.The HAZUS Flood Model is being developed for FEMA under contract with the National Institute of Building Sciences (NIBS). EQE International and project partner Michael Baker Jr. Inc. are the flood model subcontractors to NIBS. The flood model has an oversight committee composed of floodplain management practitioners from across the nation. NIBS has also created a software oversight committee to help guide the integration of the three loss estimation tools (Earthquake, Wind, and Flood). The Flood and a preview version of the Wind model will be incorporated with the earthquake model in HAZUS03 scheduled for release near the end of 2002.

2. HAZUS Flood Loss Estimation Model Model Development Approach Identify User Requirements Evaluate Alternative Methods Perform �Proof-of-Concept Exercises� Develop Software Requirements with User Input Develop Software Pilot Test Release From the beginning, the flood model has attempted to identify and incorporate key features that will enable flood model users to resolve issues and problems of importance to them. The flood model is the only HAZUS model authorized to seek user input through every phase of development. The methodology has undergone Proof-of-Concept analysis and acceptance by the flood committee. Furthermore, the project team has tested the methodology in actual applications with select users.From the beginning, the flood model has attempted to identify and incorporate key features that will enable flood model users to resolve issues and problems of importance to them. The flood model is the only HAZUS model authorized to seek user input through every phase of development. The methodology has undergone Proof-of-Concept analysis and acceptance by the flood committee. Furthermore, the project team has tested the methodology in actual applications with select users.

3. HAZUS Flood Loss Estimation Model User Requested Applications  Development and enforcement of building standards Analyzing benefits of flood warnings Benefit/cost analysis for selection of mitigation alternatives Identification of areas for building acquisition / relocation Information dissemination / public relations Disaster declaration assistance Prioritizing watersheds (Austin, TX) Analyzing impacts of new mapping (Mecklenberg, NC) Forecasting impacts of new development (Mecklenberg, NC) A listing of key user applications highlighted during user interviews.A listing of key user applications highlighted during user interviews.

4. Overview of flood methodology: From the bottom up, the basic structure of the methodology is: 1. Define Hazard, by combining the flood surface and the land surface. 2. Define and overlay the Inventory (ie, the numbers and patterns of buildings, people and other facilities). 3. Determine the Damage, by determining the depth of water at each building or facility, referring to a depth-damage curve to determine % damage, 4. Estimate losses, by multiplying the % damage by the monetary value of the building, or by referring to other curves, tables and data to determine for example the required duration of vacancy of a building, as a function of the % damage. Overview of flood methodology: From the bottom up, the basic structure of the methodology is: 1. Define Hazard, by combining the flood surface and the land surface. 2. Define and overlay the Inventory (ie, the numbers and patterns of buildings, people and other facilities). 3. Determine the Damage, by determining the depth of water at each building or facility, referring to a depth-damage curve to determine % damage, 4. Estimate losses, by multiplying the % damage by the monetary value of the building, or by referring to other curves, tables and data to determine for example the required duration of vacancy of a building, as a function of the % damage.

5. To provide flexibility, the model estimates losses at three levels. For each level, the several hazards and the various types of input data can be selectively used as appropriate, to meet the needs of the user. User effort and data is the least in Level 1, and increases with levels 2 and 3. To provide flexibility, the model estimates losses at three levels. For each level, the several hazards and the various types of input data can be selectively used as appropriate, to meet the needs of the user. User effort and data is the least in Level 1, and increases with levels 2 and 3.

7. Flood Information Tool Floodplain Boundary Self-explanatorySelf-explanatory

8. Flood Information Tool Riverine Centerline The centerline is developed by determining which grid cells are closer to the left boundary line or right boundary line of the floodplain boundary discussed in the previous slide. Those cells that fall between the two boundaries are connected to form the centerline. The centerline is developed by determining which grid cells are closer to the left boundary line or right boundary line of the floodplain boundary discussed in the previous slide. Those cells that fall between the two boundaries are connected to form the centerline.

9. Flood Information Tool Riverine Bounding Polygon The FIT assists the user in the development of the bounding polygon. The user can easily expand and contract the polygon to meet their needs. Wizard driven, the last few screens require a minimum of user interaction, but maximizes the users capabilities to modify the parameters.The FIT assists the user in the development of the bounding polygon. The user can easily expand and contract the polygon to meet their needs. Wizard driven, the last few screens require a minimum of user interaction, but maximizes the users capabilities to modify the parameters.

10. Flood Information Tool Riverine BFE Lines The user will supply the flood elevation information. Typically this will be done with cross-section lines attributed with flood elevations. Cross sections with three flood elevations attributed will allow the user to create three depth grids and interpolate to find other depths they may not have attribute information for.The user will supply the flood elevation information. Typically this will be done with cross-section lines attributed with flood elevations. Cross sections with three flood elevations attributed will allow the user to create three depth grids and interpolate to find other depths they may not have attribute information for.

11. Flood Information Tool Riverine Flood Elevation Interpolation

12. Flood Information ToolRiverine Depth Grid & Backwater Analysis After the completing the depth grid wizard, potential backwater areas are identified. The user can draw backwater polygons in these areas and assign a flood elevation to them. These areas are then appended to the flood depth grid. The user can repeat the process for other return periods and (if the user creates 3 diverse return periods) interpolate for other return periods. After the completing the depth grid wizard, potential backwater areas are identified. The user can draw backwater polygons in these areas and assign a flood elevation to them. These areas are then appended to the flood depth grid. The user can repeat the process for other return periods and (if the user creates 3 diverse return periods) interpolate for other return periods.

13. HAZUS Flood Loss Estimation Model Flood Depth Determination

14. Preview Model - Valuation Both full replacement value and depreciated replacement value estimation is supported The need for shelter is calculated using default functions relating building damage to habitability and restoration timePreview Model - Valuation Both full replacement value and depreciated replacement value estimation is supported The need for shelter is calculated using default functions relating building damage to habitability and restoration time

15. HAZUS Flood Loss Estimation Model Basement-Modified FIA Depth-Damage Curve for Structure Damage

16. Crystal Reports is included in the flood model and can be used to produce a wide range of output reports.Crystal Reports is included in the flood model and can be used to produce a wide range of output reports.