Flood Damage Reduction Analysis:
Behind the Scenes
C. Brian Patnode, PEBrown and Caldwell
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Swannanoa River Watershed– Western NC, Buncombe County– Town of Black Mountain, NC to City of Asheville, NC– 132 Sq. Mi.
Project Location
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Hurricanes Frances and Ivan– September 2004– Major flooding in Biltmore Village Flood Reduction Task Force– Flood Risk Management Project
Data collection & analysis – HEC-FDA
Project Overview
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Hydrologic Engineering Center –Flood Damage Reduction Analysis (HEC-FDA)
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HEC-FDA Development
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Quantify Flood Damages– Flood Inundation
– Economic Impact
– Appraisals
Structure Inventory Database (SID)
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ArcGIS Application– Building Identification
– Field Survey Data
– Stationing of SID
Building Identification
– FEMA Floodplain
– Impervious Polygons
– Aerial Photography
Application of ArcGIS
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Field Survey Data
– Structure Data– First Floor Elevation (FFE)– Nonstructural Screening
Application of ArcGIS
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Building Valuation
– Tax Parcels– Appraisals– Replacement Costs
Less Depreciation
Application of ArcGIS
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SID Stationing
– Convert Polygons to Points
Application of ArcGIS
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SID StationingLinear Referencing– Create Routes
Application of ArcGIS
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SID StationingLinear Referencing– Locate Features Along Route
Application of ArcGIS
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SID StationingGenerate Near Table– Assign to XS using Script
Application of ArcGIS
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Assign Damage Reaches
– Group SID by Riverand Reach Area
Application of ArcGIS
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Interface - Importing– Configure– HydEng– Economics
Data Output– Results
Damage ReachStorm EventCategory
HEC-FDA Model Inputs
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Flood Damage Reduction Analysis– Source Data Intensive
– Added Value of GISStructure Inventory DatabaseRiver StationingEconomic Damage Reaches
– Visualize Results
Summary
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Questions?
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Project Team and Partners – Thank You!