Toward Rapid Flood Mapping Using Modeled Inundation Libraries

209 Pages·2017·6.1 MB·English

Toward Rapid Flood Mapping Using Modeled Inundation Libraries

By
© 2017
Kevin Dobbs
DPhil, The University of Kansas, 2017
M.A., The University of Kansas, 2010
B.A., The University of Kansas, 2001
Submitted to the graduate degree program in Geography and the Graduate Faculty of the
University of Kansas in partial fulfillment of the requirements for the degree of Doctor of
Philosophy.

Chair: Dr. Stephen L. Egbert

Dr. Jerome E. Dobson

Dr. William C. Johnson

Dr. Xingong Li

Dr. Alfred Parr

Dr. Jude H. Kastens
Date Defended: 20 January 2017
The dissertation committee for Kevin Dobbs certifies that this is the
approved version of the following dissertation:
Toward Rapid Flood Mapping Using Modeled Inundation Libraries

Chair: Dr. Stephen L. Egbert

Date Approved: 20 January 2017

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Abstract

New methods are needed for mapping floods in near real-time that leverage
the increasing availability of remotely sensed data during flood disasters,
availability of improved elevation data, and improvements in web-based mapping
technology. There are important, ongoing improvements in elevation data
production and availability that support new methods of flood disaster mapping.
Concurrently, there is a rapid increase in the temporal frequency of high
resolution remote sensing data that is being acquired that can also support novel
application development. This study focuses on the use of prebuilt, modeled
inundation libraries capable of using traditional and novel inputs as proxies for
water surface elevation to produce near real-time estimates of flood inundation.
Thus, the research explores potential synergies between inundation libraries and
ancillary datasets with the goal of expediting the timeline for information
extraction from remotely sensed data and the improving flood inundation map
accuracy. It also profiles the computational cost of the modeling algorithm used.
The study presents strategies for production of wide area, modeled flood
inundation libraries. Gage-based interpolation methods using the FLDPLN model
showed little difference in flood extent estimation accuracy between horizontal
and vertical interpolation methods for FLDPLN model depth-to-flood (DTF)
values. Conditioning of DTF profiles using HEC-RAS modeled water surface
elevations (WSE) showed sensitivity to reference flood levels, while conditioning
with two HEC-RAS model WSE profiles showed the best results. Simulation of
imagery-derived flood boundary points as inputs to flood extent estimation using
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interpolated DTF profiles showed very good results with a very limited number of
input points. The results showed improved, asymptotic behavior when
correspondence was measured with an increasing number of input points when
compared to reference floods. Larger magnitude floods showed better
correspondence relative to moderate magnitude floods. Baseline computational
performance measures for inundation library generation with the FLDPLN
models showed that longer stream segments show better overall computational
efficiency. Some landscape factors can influence overall computational runtime,
including proximity to reservoirs and lakes, wide floodplains, and complex
tributary geometries.

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ACKNOWLEDGMENTS
I would like to thank the members of my committee, Drs. Steve Egbert
(my advisor), Alfred (Dave) Parr (my mentor), Jude Kastens (my close
collaborator), Bill Johnson, Jerry Dobson, Xingong Li for their keen insight and
suggestions in research preparations and the writing of this document. I would
also like to thank Dr. Edward Martinko for his support over these many years.

This work is dedicated to my amazing children, Willow, Finn, Persephone,
and Jet - you are my inspiration. Thank you so much for your understanding
during my absences. Now, again, I’ll try to make it up to you. And to my parents,
Kay and Luther Dobbs, whom, from day one, have sacrificed so much for me and
provided invaluable support in every way - thank you.

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TABLE OF CONTENTS

ABSTRACT ........................................................................................................... iii

ACKNOLEDGEMENTS ....................................................................................... iv

LIST OF TABLES ................................................................................................. vi

LIST OF FIGURES .............................................................................................. vii

CHAPTER

1. INTRODUCTION .......................................................................................1

2. EVALUATION OF STREAM WATER SURFACE ELEVATION PROFILE
ADJUSTMENT APPROACHES FOR USE WITH THE FLDPLN MODEL
....................................................................................................................18

3. RAPID FLOOD MAPPING APPLICATION OF THE FLDPLN
MODEL: SENSITIVITY ANALYSIS USING SIMULATED
GEOSPATIAL ANALYST INPUT ..........................................................73

4. PROFILING FLDPLN MODEL CODE FOR INSIGHTS INTO
COMPUTATIONAL PERFORMANCE.................................................128

5. SUMMARY .............................................................................................187

REFERENCES ............................................................................................195
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LIST OF TABLES

T 2-1 HEC-RAS Manning n values ..................................................................50

T 2-2 Key FSP profile values ............................................................................50

T 2-3 4.8K cms F-statistics ................................................................................51

T 2-4 1K cms F-statistics ...................................................................................51

T 3-1 HEC-RAS Manning n values ................................................................106

T 4-1 Segment processing times .....................................................................162

T 4-2 Normalized segment processing times ..................................................162

T 4-3 Overall runtimes ....................................................................................163

T 4-4 Computation cost ...................................................................................163

T 4-5 Continental scale computation costs estimates ......................................163

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LIST OF FIGURES

1-1: FLDPLN/SLIE Conceptual Framework ....................................................13

1-2: Pilot study area along the Marais des Cygnes ...........................................14

1-3: Study area for objectives 1 and 2 ...............................................................15

1-4: Study area for objective 3 ..........................................................................16

2-1: Aerial photographs taken during the peak flooding in Montgomery
County in July of 2007 ...............................................................................52

2-2: ASTER Flood image from 2007 SE Kansas Flood ...................................53

2-3: FLDPLN/SLIE Conceptual Framework ....................................................54

2-4: USGS Independence Gage Map ................................................................55

2-5: NWS Coffeyville Gage Map ......................................................................55

2-6: USGS Coffeyville Gage Map ....................................................................55

2-7: Study area LULC and Terrain Data ...........................................................56

2-8: HEC-RAS Flood Depth Maps ...................................................................56

2-9: HEC-RAS 4.8K WSE Map ........................................................................57

2-10: HEC-RAS 1K WSE Map ...........................................................................58

2-11: FPP links to FSP plots series 1 ..................................................................59

2-12: FPP links to FSP plots series 2 ..................................................................60

2-13: FPP links to FSP plots series 3 ..................................................................61

2-14: Unique FSP by DTF interval plot ..............................................................62

2-15: FPP by DTF interval plot ...........................................................................63

2-16: FAC profile ................................................................................................64

2-17: DTF interpolation plot ...............................................................................64

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2-18: DTF interpolation difference profile ..........................................................65

2-19: Single DTF inundation maps .....................................................................66

2-20: 4.8K WSE profiles .....................................................................................67

2-21: 1K WSE profiles ........................................................................................67

2-22: 4.8K conditioned DTF profile....................................................................68

2-23: 1K conditioned DTF profile.......................................................................68

2-24: Bound-conditioned DTF profile ................................................................69

2-25: Bound-conditioned WSE profile................................................................69

3-1: FLDPLN/SLIE Conceptual Framework ..................................................107

3-2: F-statistic vs. stage for all model pairings and between all models .........108

3-3: Total area flooded with each model vs. stage ..........................................108

3-4: ASTER Flood image from 2007 SE Kansas Flood .................................109

3-5: Study area LULC and Terrain Data .........................................................110

3-6: HEC-RAS terrain with 20m grid .............................................................111

3-7: HEC-RAS terrain with 10m grid and breaklines .....................................111

3-8: HEC-RAS 1K cms depth detail ...............................................................112

3-9: HEC-RAS 4.8K cms depth detail ............................................................112

3-10: HEC-RAS 1K cms velocity detail ...........................................................113

3-11: HEC-RAS 4.8K cms velocity detail ........................................................113

3-12: HEC-RAS Flood Depth Maps .................................................................114

3-13: SBP map...................................................................................................115

3-14: SBP detail map .........................................................................................116

3-15: 2m vs 5m DEM elevation plot ................................................................117

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3-16: 2m vs 5m slope plot .................................................................................118

3-17: Right / Left bank profile plot ...................................................................119

3-18: 5-100 SBP F-statistic plot ........................................................................120

3-19: 5-1000 SBP F-statistic plot ......................................................................121

3-20: 5-10,000 SBP F-statistic plot ...................................................................122

3-21: 5-100 SBP vs unique SBS plot ................................................................122

3-22: 5-1000 SBP vs unique SBS plot ..............................................................123

3-23: 5-10,000 SBP vs unique SBS plot ...........................................................123

3-24: Unique FSP by DTF interval plot ............................................................124

3-25: DTF distributions .....................................................................................125

4-1: FLDPLN/SLIE Conceptual Framework ..................................................164

4-2: US gaged stream network ........................................................................165

4-3: Southeast Kansas study area ....................................................................166

4-4: ACF node specifications ..........................................................................166

4-5: 15m DTF composite map.........................................................................167

4-6: Distribution of segment lengths, 195 segs ...............................................168

4-7: Distribution of segment runtimes, 195 segs .............................................168

4-8: Runtimes per Segments vs Segment Length, 195 segs ............................169

4-9: Segment Starting FAC vs Runtimes, 195 segs ........................................169

4-10: Distribution of Runtimes/Length, 194 segs .............................................170

4-11: Runtimes per FSP vs Segment Length, 194 segs .....................................170

4-12: Semilog Runtimes per FSP vs Segment Length, 194 segs ......................171

4-13: Segment Total Runtimes vs FPP Area, 195 segs .....................................171

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