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A GIS-Based Flood A GIS-Based Flood Inundation Mapping and Inundation Mapping and

Analysis Pilot ProjectAnalysis Pilot Project

Indiana GIS ConferenceIndiana GIS ConferenceFebruary 19-20, 2008February 19-20, 2008

John Buechler, The Polis CenterJohn Buechler, The Polis CenterMoon Kim, USGS-WSCMoon Kim, USGS-WSC

Presentation OutlinePresentation Outline• Introduction Introduction

• Pilot Study OverviewPilot Study Overview

• Near Real Time AnalysisNear Real Time Analysis

• Damage AssessmentDamage Assessment

• GIS VisualizationGIS Visualization

• What’s NextWhat’s Next

Flood-Inundation Mapping Pilot Flood-Inundation Mapping Pilot ProjectProject

• Generate current and forecast flood-Generate current and forecast flood-inundation maps: USGS and NWS inundation maps: USGS and NWS datadata

• Generate maps for import to HAZUS-Generate maps for import to HAZUS-MHMH

• Serve maps visually through WebServe maps visually through Web

Collaborative effortCollaborative effort• Silver Jackets: A Natural Hazard Mitigation TeamSilver Jackets: A Natural Hazard Mitigation Team• City of Indianapolis City of Indianapolis • IMAGISIMAGIS• Indianapolis Museum of ARTIndianapolis Museum of ART• INDHSINDHS• USACEUSACE• IDNRIDNR• NWSNWS• USGSUSGS• PolisPolis

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

Study Area

• Ravenswood floods frequently and often Ravenswood floods frequently and often damage is incurreddamage is incurred

• IMA Virginia B. Fairbanks Art and Nature IMA Virginia B. Fairbanks Art and Nature Park in is partially situated in the flood Park in is partially situated in the flood plain: occasional floodingplain: occasional flooding

• Availability of high-resolution digital Availability of high-resolution digital elevation data, detailed building inventory elevation data, detailed building inventory data, USGS/NWS data and extensive historic data, USGS/NWS data and extensive historic high-water mark and flood elevation datahigh-water mark and flood elevation data

Why Ravenswood?Why Ravenswood?

ApproachApproach• Compile GIS and HAZUS-MH datasetsCompile GIS and HAZUS-MH datasets

• Calibrate, verify and implement hydraulic model Calibrate, verify and implement hydraulic model “FastMECH”“FastMECH”

• Automate data retrieval from USGS/NWS and Automate data retrieval from USGS/NWS and create input files for FastMECHcreate input files for FastMECH

• Generate a flood grid for a simulated flood and Generate a flood grid for a simulated flood and perform a HAZUS-MH analysisperform a HAZUS-MH analysis

• Install, test, and implement web and map serversInstall, test, and implement web and map servers

Data needsData needs• FastMECHFastMECH

– Observed and predicted stream-flow and Observed and predicted stream-flow and water-surface elevation data (USGS, NWS)water-surface elevation data (USGS, NWS)

– High-resolution digital elevation dataHigh-resolution digital elevation data

• HAZUS-MHHAZUS-MH– Observed and predicted flood-inundation Observed and predicted flood-inundation

maps from FastMECHmaps from FastMECH– Default hazard, inventory and damage Default hazard, inventory and damage

information for level 1 analysis and more information for level 1 analysis and more detailed local information for the level 2 detailed local information for the level 2 and 3 analysesand 3 analyses

Data FlowData Flow

• USGS provides real-time river USGS provides real-time river stagestage and and streamflowstreamflow from from streamgagesstreamgages

• NWS uses streamgage data and NWS uses streamgage data and sophisticated computer models to sophisticated computer models to generate generate forecastsforecasts of of stage/streamflowstage/streamflow

NWS dataNWS data

• Flow and water-surface elevation Flow and water-surface elevation forecasts are generated by the NWS forecasts are generated by the NWS River Forecast CentersRiver Forecast Centers

• Forecasts are based on regional Forecasts are based on regional rainfall-runoff relationsrainfall-runoff relations

• Automated program will download the Automated program will download the forecast data (XML) through the NWS forecast data (XML) through the NWS Advanced Hydrologic Prediction Service Advanced Hydrologic Prediction Service

FastMECHFastMECH• Two-dimensional hydraulic flow Two-dimensional hydraulic flow

modelmodel

• Allows simulation of long reachesAllows simulation of long reaches

• Can handle flow regime changesCan handle flow regime changes

• Output: Water surface (depths), Output: Water surface (depths), water velocity, flood arrival timeswater velocity, flood arrival times

What is HAZUS-MH? What is HAZUS-MH?

• FEMA created tool that helps FEMA created tool that helps communities reduce loss to property communities reduce loss to property and life that may result from natural and life that may result from natural disasters.disasters.

• ArcGIS 9.2 extension. Requires ArcGIS 9.2 extension. Requires installation of Spatial Analyst 9.x (for installation of Spatial Analyst 9.x (for flood modeling)flood modeling)

• Available from FEMA free of chargeAvailable from FEMA free of charge

MethodologyMethodology

Earthquake Flood Hurricane

1 - 18

Damage FunctionsDamage Functions

Depth of water

Dam

ag

e a

s %

of

rep

lace

men

t co

st

0 ft 5 ft 10 ft 15 ft

0%

5

0%

10

0%

• Damage curves are assigned to each Damage curves are assigned to each building specific occupancy class and building specific occupancy class and each facilityeach facility

Curves vary by hazard. This example represents a flood hazard.

Over 800 curves – and you can create your own as well!

Levels of AnalysisLevels of Analysis

Level 3

Level 2

Level 1

Combinations of local and

default hazard, building, and damage data

Default hazard, inventory, and damage information

Inputdata hazard

specificRequired

User Effort and Sophistication

20FEMA Presentation – August 2007

User Defined Flood Depth User Defined Flood Depth GridGrid

• HAZUS-MH allows users HAZUS-MH allows users to point to one or more to point to one or more existing flood depth existing flood depth grids.grids.

• USGS provided web-USGS provided web-based delivery of GIS based delivery of GIS maps and downloadable maps and downloadable flood grids for HAZUS-MH flood grids for HAZUS-MH analysisanalysis

User Defined Depth GridUser Defined Depth Grid

• Assign the Assign the depth grid, depth grid, along withalong with

• All analysis All analysis output output options are options are available.available.

HAZUS-MH Ravenswood HAZUS-MH Ravenswood AnalysisAnalysis

• USGS provided web-based delivery of USGS provided web-based delivery of GIS maps and downloadable flood GIS maps and downloadable flood grids for HAZUS-MH analysisgrids for HAZUS-MH analysis

• HAZUS-MH, a mitigation tool, could HAZUS-MH, a mitigation tool, could then also be used as a response and then also be used as a response and recovery toolrecovery tool

Data FlowData Flow

ProductsProducts• Web-based near-real-time flood-Web-based near-real-time flood-

inundation maps updated hourly.inundation maps updated hourly.• Web-based forecast maps updated Web-based forecast maps updated

every 6 hrs per NWSevery 6 hrs per NWS• Downloadable flood grids for HAZUS-MHDownloadable flood grids for HAZUS-MH• Results from the HAZUS-MH analysisResults from the HAZUS-MH analysis• USGS ReportUSGS Report• Evaluation of models/techniquesEvaluation of models/techniques

What’s Next?What’s Next?

SummarySummary• Products will come with disclaimers and Products will come with disclaimers and

error estimateserror estimates

• Highly expandable on a geographic basisHighly expandable on a geographic basis

• Many possibilities for future enhancements Many possibilities for future enhancements e.g. depth/velocity data for damage e.g. depth/velocity data for damage estimatesestimates

• Expands HAZUS-MH from a mitigation-only Expands HAZUS-MH from a mitigation-only to a response toolto a response tool

• Web and map server maintenance may be Web and map server maintenance may be transferred to NWS and/or FEMAtransferred to NWS and/or FEMA

Questions?Questions?

• Contact InformationContact Information– John Buechler: John Buechler: jobuechl@iupui.edujobuechl@iupui.edu– Moon Kim: Moon Kim: mkim@usgs.gov