San Marcos FloodingSan Marcos Flooding

EAGLEEAGLE

Project ManagerProject ManagerJustine WilliamsJustine Williams

Assistant ManagerAssistant ManagerJoshua BridgesJoshua BridgesWeb MasterWeb Master

Alexander NankervisAlexander NankervisGIS AnalystsGIS Analysts David SmithDavid Smith

Clayton HolbrookClayton Holbrook

San Marcos Flood AnalysisSan Marcos Flood Analysis

• Introduction: San Marcos has a Introduction: San Marcos has a potential for flash flooding due to its potential for flash flooding due to its unique geological aspects.unique geological aspects.

• Scope: San Marcos City LimitsScope: San Marcos City Limits

San Marcos Flood AnalysisSan Marcos Flood Analysis

• Purpose: Identify low-water crossings, Purpose: Identify low-water crossings, floodplains, potentially dangerous floodplains, potentially dangerous road segments, locations for new fire road segments, locations for new fire rescue stations, new shelter rescue stations, new shelter locations, and determine if there is locations, and determine if there is any correlation between the Hispanic any correlation between the Hispanic population and flood damages.population and flood damages.

Literature ReviewLiterature Review

• October 1998 flood reportOctober 1998 flood report– Four phases of the disastersFour phases of the disasters

•Planning, Response, Recovery, MitigationPlanning, Response, Recovery, Mitigation

– Damage assessmentDamage assessment– Evacuation operationsEvacuation operations– Rescue OperationsRescue Operations– Time-lineTime-line– Rain gauge readingsRain gauge readings– San Marcos Road Improvement PlanSan Marcos Road Improvement Plan

DataData• San Marcos DOQQs (Digital Ortho Quarter Quadrangles) and San Marcos DOQQs (Digital Ortho Quarter Quadrangles) and

city limitcity limit

• Census 2000 Hays County TIGER/Line data (census blocks, Census 2000 Hays County TIGER/Line data (census blocks, roads network)roads network)

• Census 2000 block group dataCensus 2000 block group data

• San Marcos 100 and 500 year floodplains, 1998 flood San Marcos 100 and 500 year floodplains, 1998 flood damage, neighborhoods, and Hays County streamsdamage, neighborhoods, and Hays County streams

• Low water crossingsLow water crossings

• San Marcos schools, fire stations, hospital, and shelter San Marcos schools, fire stations, hospital, and shelter locationslocations

MethodologyMethodology

• Determine safe road areasDetermine safe road areas• Identify regions through network Identify regions through network

analysisanalysis• Locate major intersections of roads Locate major intersections of roads

and floodplainand floodplain• Propose new fire service and shelter Propose new fire service and shelter

locationslocations• Find correlation between Hispanic Find correlation between Hispanic

population and flood damagepopulation and flood damage

#0#0

#0

#0

#0

San Marcos Flood Analysis: the 1998 Flood Damages

±

Legend

Rivers/Streams

Roads/Streets

City Boundaries

1998 Flood Damage

Affected

Minor

Major

Destroyed

#0 Low Water Crossings

100 Year Floodplain

500 Year Floodplain0 0.5 10.25 Miles

EAGLEGeo. 442712-2005

Óñ

Óñ

ÓñÓñ

Óñ

San Marcos Fire Station Coverage

Legend

Fire Service Areas

Northwest

South

Southwest

Northeast

Óñ Fire Station

Óñ Proposed Station

100yr Floodplain

Road

City Limit

±0 0.5 10.25 MilesEAGLE

Geo. 442712-2005

nn

nn

n

nn

n

D

D

D

D

D

DD D

D

D

!H

®v

!H

!H

San Marcos Evacuation Shelter Coverage and Flood Crossings

Legend

n School

®v Hospital

!H Shelter

!H Proposed Shelter

D Flood Crossing

Shelter Coverage

Northwest

South

Northeast

100yr Floodplain

Road

City Limit

±0 0.5 10.25 MilesEAGLE

Geo. 442712-2005

San Marcos Hispanic Population and Flood Damage Correlation

Legend

Damage Correlation

Higher is More

0 - 14

15 - 45

46 - 79

80 - 142

143 - 212

100yr Floodplain

City Limit

±0 0.5 10.25 MilesEAGLE

Geo. 442712-2005

Final DeliverablesFinal Deliverables

• ReportReport

• PosterPoster

• Web SiteWeb Site

• CDCD