*Evacuation Safety PlannersEvacuation Safety Planners*

Jason Haycock Robert Broussard Colleen Grentz Project Manager Analyst & Webmaster Analyst &

Project Designer

Floodplain and Evacuation Floodplain and Evacuation Network Analysis of the Network Analysis of the

San Marcos, Texas San Marcos, Texas Extraterritorial JurisdictionExtraterritorial Jurisdiction

Presentation Summary

• Introduction & Objectives• Data• Software• Methodology & Results• Timeline• Budget• Final Deliverables• Participation• Conclusion• Proposed Research

IntroductionIntroduction::

• Objectives for this project were arrived upon through correspondence with the City of San Marcos, Texas

• Two floods in the past 10 years caused water levels to surpass the 500 year floodplain

• Flood management used to reduce damage and sustain life in at-risk communities

ESP’s ObjectivesESP’s Objectives:

• Determine low water crossings

• Locate potential flood risk areas

• Designate various emergency shelters

• Determine evacuation service areas coupled with emergency shelters

• Evaluate population vulnerability

Scope:

• This study covered the City of San Marcos, Texas and the associated Extraterritorial Jurisdiction.

Data Sources

• City of San Marcos, Texas• FEMA• Texas Hazard Mitigation Package• US Census Bureau

Data Files

• FEMA 100 Year & 500 Year Floodplains

• October 1998 Flood Line• October 1998 Damage Assessment

Table• Centerline Road Network• Extraterritorial Jurisdiction• Land Parcels

Data Files

• One Way Roads • Current Infrastructure• Rivers• Major Streams• US Census Data• Population Vulnerability

Data Description• Projection:

– Texas State Plane Coordinate System– NAD 1983 Texas South Central Zone

• Metadata:– Compiled using Federal Geographic

Data Committee Standards

Software

• Microsoft Excel– Tabular data formation

• ESRI ArcGIS 9– ArcMap 9.1

• Network Analyst• Spatial Analyst

– ArcCatolog 9.1• Data Management• Metadata

Methodology & Results• Low water crossings determined by

where the floodway crossed a street or highway

• Damage assessment from the 1998 flood done by assigning damages to parcels

• Proposed emergency shelters for each designated service area- used a 12 square foot plan per person for

each shelter to figure out the capacity for

each building

San Marcos Low Water Crossing

Methodology & Results

• Identify potential flood areas using overlay analysis

• Assess flood vulnerability based on Texas Hazard Mitigation Package data

• Developed network service areas which lead evacuees to emergency shelters

Methodology & Results

Vulnerability Assessment• Texas Hazard Mitigation Package

– Population vulnerability to floods• V_FACTOR was created using the Risk Zone

values for floods from the Flood Risk Zones dataset.

• V_SCORE was calculated as [POP2000 / V_FACTOR]

Service Areas• The primary shelters in the entire region

could house around 78,035 people without taking into account items inside the buildings such as chairs, desks, tables or pews in churches.

• The two proposed shelters have no designated amount of square footage since they do not yet exist so they are not incorporated in the estimates.

Hazardous Zones

• We found a problem with two areas of the ETJ being potential hazard zones.

• These are the areas that are bound by low water crossings that do not contain a proposed emergency shelter.

Timeline

Week 1 2 3 4 5 6 7 8 9 10

DatesSept.25th

Oct.2nd

Oct.9th

Oct.16th

Oct.23rd

Oct.30th

Nov.6th

Nov.13th

Nov.20th

Nov.27th

Data Collection

Data Processing

Data Analysis

Interpretation

Deliverables andReview

Budget:

Data Collection ‘$570Data Analysis $10,650 Systems Management ‘

$3,000Equipment $10,756 Software License $1,750 ------------Total $26,726

Deliverables:

• Website http://geosites.evans.txstate.edu/~g4427f06-01/

• Multiple copies of CD’s containing:– All data & maps developed for this

project– Metadata for all layers– Written reports– Professional poster

ConclusionConclusion:

• Discovery of valuable information that will allow the City of San Marcos, Texas to understand more thoroughly potential flood areas, sustain emergency preparedness, reduce damage to infrastructure, and save lives.

Participation

• Jason Haycock -- Team Management and Analysis– Evacuation network analysis– Floodplain and flood line analysis– Population vulnerability assessment

• Colleen Grentz -- Project Design and Analysis– Risk assessment analysis– Determination of emergency shelters– Determination of low water crossings

• Robert Broussard – Website Management and Analysis– Metadata formation– Data management – Cooperative website development

Proposed Research:

• Development of an interactive online evacuation network that instantly illustrates least cost pathways from specific geographic locations.

Proposed Research:

• Application of additional location analysis and population assessment– ESRI’s Business Analyst Online

Questions?