1 A GIS-Based Flood Inundation Mapping and Analysis Pilot Project Indiana GIS Conference February 19-20, 2008 John Buechler, The Polis Center Moon Kim, USGS-WSC

Presentation Outline Introduction Introduction Pilot Study Overview Pilot Study Overview Near Real Time Analysis Near Real Time Analysis Damage Assessment Damage Assessment GIS Visualization GIS Visualization What’s Next What’s Next

Flood-Inundation Mapping Pilot Project Generate current and forecast flood- inundation maps: USGS and NWS data Generate current and forecast flood- inundation maps: USGS and NWS data Generate maps for import to HAZUS-MH Generate maps for import to HAZUS-MH Serve maps visually through Web Serve maps visually through Web

Collaborative effort Silver Jackets: A Natural Hazard Mitigation Team Silver Jackets: A Natural Hazard Mitigation Team City of Indianapolis City of Indianapolis IMAGIS IMAGIS Indianapolis Museum of ART Indianapolis Museum of ART INDHS INDHS USACE USACE IDNR IDNR NWS NWS USGS USGS Polis Polis

Observed and Predicted Flood-Inundation Mapping and HAZUS-MH Analysis Using the Ravenswood Area of Indianapolis as a Pilot Study Study Area

Ravenswood floods frequently and often damage is incurred Ravenswood floods frequently and often damage is incurred IMA Virginia B. Fairbanks Art and Nature Park in is partially situated in the flood plain: occasional flooding IMA Virginia B. Fairbanks Art and Nature Park in is partially situated in the flood plain: occasional flooding Availability of high-resolution digital elevation data, detailed building inventory data, USGS/NWS data and extensive historic high-water mark and flood elevation data Availability of high-resolution digital elevation data, detailed building inventory data, USGS/NWS data and extensive historic high-water mark and flood elevation data Why Ravenswood?

Approach Compile GIS and HAZUS-MH datasets Compile GIS and HAZUS-MH datasets Calibrate, verify and implement hydraulic model “FastMECH” Calibrate, verify and implement hydraulic model “FastMECH” Automate data retrieval from USGS/NWS and create input files for FastMECH Automate data retrieval from USGS/NWS and create input files for FastMECH Generate a flood grid for a simulated flood and perform a HAZUS-MH analysis Generate a flood grid for a simulated flood and perform a HAZUS-MH analysis Install, test, and implement web and map servers Install, test, and implement web and map servers

Data needs FastMECH FastMECH –Observed and predicted stream-flow and water-surface elevation data (USGS, NWS) –High-resolution digital elevation data HAZUS-MH HAZUS-MH –Observed and predicted flood-inundation maps from FastMECH –Default hazard, inventory and damage information for level 1 analysis and more detailed local information for the level 2 and 3 analyses

Data Flow

USGS provides real-time river stage and streamflow from streamgages USGS provides real-time river stage and streamflow from streamgages NWS uses streamgage data and sophisticated computer models to generate forecasts of stage/streamflow NWS uses streamgage data and sophisticated computer models to generate forecasts of stage/streamflow

NWS data Flow and water-surface elevation forecasts are generated by the NWS River Forecast Centers Flow and water-surface elevation forecasts are generated by the NWS River Forecast Centers Forecasts are based on regional rainfall- runoff relations Forecasts are based on regional rainfall- runoff relations Automated program will download the forecast data (XML) through the NWS Advanced Hydrologic Prediction Service Automated program will download the forecast data (XML) through the NWS Advanced Hydrologic Prediction Service

FastMECH Two-dimensional hydraulic flow model Two-dimensional hydraulic flow model Allows simulation of long reaches Allows simulation of long reaches Can handle flow regime changes Can handle flow regime changes Output: Water surface (depths), water velocity, flood arrival times Output: Water surface (depths), water velocity, flood arrival times

What is HAZUS-MH? FEMA created tool that helps communities reduce loss to property and life that may result from natural disasters. FEMA created tool that helps communities reduce loss to property and life that may result from natural disasters. ArcGIS 9.2 extension. Requires installation of Spatial Analyst 9.x (for flood modeling) ArcGIS 9.2 extension. Requires installation of Spatial Analyst 9.x (for flood modeling) Available from FEMA free of charge Available from FEMA free of charge

Methodology EarthquakeFlood Hurricane

Damage Functions Depth of water Damage as % of replacement cost 0 ft 5 ft10 ft15 ft 0% 50% 100% Damage curves are assigned to each building specific occupancy class and each facility Damage curves are assigned to each building specific occupancy class and each facility Curves vary by hazard. This example represents a flood hazard. Over 800 curves – and you can create your own as well!

Levels of Analysis Level 3 Level 2 Level 1 Combinations of local and default hazard, building, and damage data Default hazard, inventory, and damage information Input data hazard specific Required User Effort and Sophistication

20FEMA Presentation – August 2007 User Defined Flood Depth Grid HAZUS-MH allows users to point to one or more existing flood depth grids. HAZUS-MH allows users to point to one or more existing flood depth grids. USGS provided web-based delivery of GIS maps and downloadable flood grids for HAZUS-MH analysis USGS provided web-based delivery of GIS maps and downloadable flood grids for HAZUS-MH analysis

User Defined Depth Grid Assign the depth grid, along with Assign the depth grid, along with All analysis output options are available. All analysis output options are available.

HAZUS-MH Ravenswood Analysis USGS provided web-based delivery of GIS maps and downloadable flood grids for HAZUS-MH analysis USGS provided web-based delivery of GIS maps and downloadable flood grids for HAZUS-MH analysis HAZUS-MH, a mitigation tool, could then also be used as a response and recovery tool HAZUS-MH, a mitigation tool, could then also be used as a response and recovery tool

Data Flow

Products Web-based near-real-time flood- inundation maps updated hourly. Web-based near-real-time flood- inundation maps updated hourly. Web-based forecast maps updated every 6 hrs per NWS Web-based forecast maps updated every 6 hrs per NWS Downloadable flood grids for HAZUS-MH Downloadable flood grids for HAZUS-MH Results from the HAZUS-MH analysis Results from the HAZUS-MH analysis USGS Report USGS Report Evaluation of models/techniques Evaluation of models/techniques

What’s Next?

Summary Products will come with disclaimers and error estimates Products will come with disclaimers and error estimates Highly expandable on a geographic basis Highly expandable on a geographic basis Many possibilities for future enhancements e.g. depth/velocity data for damage estimates Many possibilities for future enhancements e.g. depth/velocity data for damage estimates Expands HAZUS-MH from a mitigation-only to a response tool Expands HAZUS-MH from a mitigation-only to a response tool Web and map server maintenance may be transferred to NWS and/or FEMA Web and map server maintenance may be transferred to NWS and/or FEMA

Questions? Contact Information Contact Information –John Buechler: –John Buechler: –Moon Kim: