flood damage reduction analysis - behind the scenes

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!