Methodology for Predicting Channel Migration (2004)

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i CONTENTS ABSTRACT...........................................................................................................................................ix ACKNOWLEDGMENTS ......................................................................................................................x METHODOLOGY FOR PREDICTING CHANNEL MIGRATION..............................................1 SUMMARY..............................................................................................................................1 CHAPTER 1 Introduction and Research Approach .......................................................................4 PROBLEM STATEMENT AND RESEARCH OBJECTIVES ...............................................4 SCOPE OF RESEARCH ..........................................................................................................5 RESEARCH APPROACH .......................................................................................................6 Task 1 – Literature Review...............................................................................................8 Task 2 – Document Case Histories ...................................................................................9 Task 3 – Assemble and Evaluate Existing Data................................................................9 Task 4 – First Interim Report............................................................................................9 Task 5 – Acquire Data and Develop Methodologies ........................................................9 Task 6 – Test and Evaluate Methodology.........................................................................9 Task 7 – Second Interim Report .......................................................................................9 Task 8 – State Evaluation .................................................................................................9 Task 9 – Compile and Archive Data Base ........................................................................9 Task 10 – Prepare an Aerial Photo Comparison Handbook .............................................9 Task 11 – Submit Final Report .......................................................................................10 CHAPTER 2 Findings ......................................................................................................................11 LITERATURE REVIEW .......................................................................................................11 Introduction.....................................................................................................................11 Fundamental Aspects of Meandering .............................................................................11 Flow Patterns, Velocity Distributions, and Boundary Shear Stress Distribution at Bends ......................................................................................................12 Numerical Models of Flow and Sediment Processes at Bends .......................................15 Meander Planform Characteristics..................................................................................16 Historical and Monitoring Studies of Meandering Rivers ..............................................22 Factors Affecting Rates of Meander Change ..................................................................25 Discharge...............................................................................................................26 Mobility of Bed Material........................................................................................26 Sediment Supply .....................................................................................................27 Erodibility of Bank Materials ................................................................................27 Bank Geotechnics...................................................................................................28 Riparian Vegetation and Land-Use .......................................................................29 Basal Cleanout.......................................................................................................30 Human Intervention ...............................................................................................30 Overview ................................................................................................................31

ii Styles of Meander Change ..............................................................................................34 Conceptual and Empirical Models of Meander Evolution..............................................36 Conceptual Models of Meander Migration............................................................36 Numerical Models of Meander Migration .............................................................38 Technical Problems Related to Meander Measurement, Characterization, and Monitoring ..............................................................................................................42 Summary .........................................................................................................................42 EVALUATION OF ANALYSIS OPTIONS ..........................................................................43 The Johns Hopkins Study ...............................................................................................43 Empirical Relationships.........................................................................................44 Bend-Flow Meander Migration Models ................................................................44 The Federal Emergency Management Agency Evaluation.............................................45 Riverine Erosion ....................................................................................................46 Evaluation of Channel Changes ............................................................................47 Conclusions from the FEMA Study........................................................................47 Data Needs ......................................................................................................................48 Empirical Approach...............................................................................................48 Deterministic Approach .........................................................................................49 Summary .........................................................................................................................51 CLASSIFICATION AND SCREENING PROCEDURES ....................................................51 Objective .........................................................................................................................51 Classification Concepts...................................................................................................51 Classification and Screening...........................................................................................52 REGRESSION ANALYSIS ...................................................................................................55 Introduction.....................................................................................................................55 Justification of the Classification System .......................................................................55 Comparison with Other Studies ......................................................................................58 Migration Prediction .......................................................................................................60 Frequency Analysis.........................................................................................................61 Summary .........................................................................................................................64 THE HANDBOOK.................................................................................................................64 Overview.........................................................................................................................64 Application Of Photogrammetry To Meander Migration Analysis ................................66 Map and Aerial Photography Sources ............................................................................66 Map and Aerial Photo Comparison Techniques .............................................................69 Manual Overlay Techniques .................................................................................69 Computer Supported Techniques ..........................................................................70 GIS-Based Measurement and Extrapolation Techniques .....................................71 ARCHIVE DATA BASE........................................................................................................72 Overview.........................................................................................................................72 Data Base Structure.........................................................................................................73 Summary .........................................................................................................................74 CHAPTER 3 Interpretation, Appraisal, Application ....................................................................77 OVERVIEW ...........................................................................................................................77 DATA COLLECTION ...........................................................................................................77 Brice Data Set .................................................................................................................78 Schumm Great Plains Rivers Data Set............................................................................78 Minnesota Rivers Data Set..............................................................................................78

iii Ayres Associates Data Set ..............................................................................................79 Other Data Sets ...............................................................................................................79 Acquisition of Updated Aerial Photos, Maps, and Discharge Data ................................79 MEASUREMENT PROCEDURES .......................................................................................80 Measurements Using MicroStation® ..............................................................................80 Bankline Delineation ............................................................................................80 Valley Width and Orientation ...............................................................................81 Slope and Sinuosity ...............................................................................................82 Measuring Meander Migration .......................................................................................83 GIS Measurement Tool .........................................................................................85 Radius of Curvature..............................................................................................86 Meander Bend Orientation ...................................................................................86 Meander Wavelength and Amplitude....................................................................86 Channel Width .......................................................................................................87 SCREENING AND CLASSIFICATION PROCEDURES ....................................................87 Screening ........................................................................................................................87 Meander Classification ...................................................................................................87 Summary .........................................................................................................................92 AERIAL PHOTO COMPARISON METHODOLOGY.........................................................95 Manual Overlay and Prediction ......................................................................................95 Sources of Error and Limitations ..................................................................................102 Map and Aerial Photo Errors and Limitations...................................................102 Measurement Error.............................................................................................104 Limitations of Overlay Techniques .....................................................................104 GIS PREDICTOR RESULTS...............................................................................................106 REGRESSION ANALYSIS .................................................................................................111 Expansion......................................................................................................................112 Translation and Extension.............................................................................................114 EVALUATION AND TESTING OF THE METHODOLOGY...........................................116 Overview.......................................................................................................................116 Evaluation Procedure ....................................................................................................117 Simple Overlay Technique ..................................................................................117 Computer Assisted (PowerPoint) Overlay Technique ........................................120 ArcView-Based Bend Measurement and Migration Predictor Technique..........121 Testing Results..............................................................................................................121 Simple Overlay – Sacramento River Site ............................................................121 Computer Assisted –Minnesota River Site ..........................................................122 ArcView Based Measurement and Prediction.....................................................122 Statistical Analysis of Test Results......................................................................122 Summary of State DOT Comments ..............................................................................125 Alabama ........................................................................................................................125 Alaska ...........................................................................................................................126 California ......................................................................................................................126 Maryland.......................................................................................................................128 Nevada ..........................................................................................................................129 Texas(City of Austin) ...................................................................................................129 Wyoming ......................................................................................................................130 Summary and Planned Response to State Evaluation...................................................131 APPLICATIONS AND IMPLEMENTATION....................................................................132 The Handbook...............................................................................................................132

iv The Archive Data Base .................................................................................................133 Implementation .............................................................................................................134 The Audience.......................................................................................................134 Impediments to Implementation ..........................................................................134 Leadership in Application...................................................................................134 Activities for Implementation ..............................................................................135 Criteria for Success.............................................................................................136 CHAPTER 4 Conclusions and Suggested Research ....................................................................137 CONCLUSIONS...................................................................................................................137 The Problem..................................................................................................................137 The Methodology..........................................................................................................138 Literature Review................................................................................................138 Analysis Options .................................................................................................139 The Handbook .....................................................................................................140 The Archive Data Base .................................................................................................143 SUGGESTED RESEARCH .................................................................................................143 REFERENCES..................................................................................................................................145 APPENDIX A – Bibliography......................................................................................................... A-1 APPENDIX B – Data Base Index ....................................................................................................B-1 APPENDIX C – Beta Testing Results .............................................................................................C-1

v LIST OF FIGURES Figure 1. Summary diagram for flow pattern and cross-sectional morphology at a bend apex.......13 Figure 2. Generalized sketch of flow patterns and separation at very tight bends...........................14 Figure 3. Definition of key planform parameters.............................................................................16 Figure 4. Simple mathematical functions used to represent meander shape....................................17 Figure 5. Brice classification of single-thread rivers based on the degree and character of sinuosity ........................................................................................................21 Figure 6. Schematic diagram showing in planform features and geomorphic surfaces associated with meander bends .........................................................................................23 Figure 7. Erosion rate as a function of bend curvature for data from Hickin and Nanson and other authors...............................................................................................................24 Figure 8. Controls on river patterns .................................................................................................32 Figure 9. Styles of change displayed by meander bends .................................................................34 Figure 10. Channel pattern classification devised by Brice...............................................................53 Figure 11. Modified Brice classification............................................................................................54 Figure 12. Modes of meander bend movement..................................................................................56 Figure 13. Cumulative percentage of Apex Bend Movement in ft/yr................................................57 Figure 14. Cumulative percentage of Apex Bend Movement in channel widths/yr ..........................57 Figure 15. Migration Rate (MR/W) versus Radius of Curvature/Width ...........................................59 Figure 16. Apex Movement versus Radius of Curvature/Width........................................................59 Figure 17. Apex Movement versus Channel Width...........................................................................60 Figure 18. Change in Radius of Curvature versus Radius of Curvature/Width (C Sites)..................61 Figure 19. Cumulative percentage of extension in channel widths per year......................................61 Figure 20. Cumulative percentage of translation in channel widths per year ....................................62 Figure 21. Example movement frequencies.......................................................................................63 Figure 22. Hierarchy for Archive Data Base .....................................................................................73 Figure 23. Example directory for the Archive Data Base..................................................................74

vi Figure 24. General Data spreadsheet containing the existing data and aerial photograph with bend locations for a site on the Brazos River, Texas ...............................................75 Figure 25. Bend spreadsheet containing measured and existing data for a bend on the Brazos River, Texas .........................................................................................................76 Figure 26. Simple and compound channel orientations used in valley slope determinations............83 Figure 27. Measuring meander migration..........................................................................................84 Figure 28. Some of the bend measurements made using the Data Logger ........................................86 Figure 29. Channel classification and relative stability as hydraulic factors are varied ....................89 Figure 30. The range of alluvial channel patterns..............................................................................91 Figure 31. Idealized long profile from hillslopes and unchanneled hollows downslope through the channel network showing the general distribution of alluvial channel types ............92 Figure 32. Key to classification of rivers in Rosgen's method...........................................................94 Figure 33. Longitudinal, cross-sectional, and planform views of major stream types in Rosgen's method ..............................................................................................................95 Figure 34. Aerial photograph of a site on the White River in Indiana showing four registration points (circles designated a through d) common to the 1966 aerial photo ......................................................................................................................96 Figure 35. Aerial photo of a site on the White River in Indiana showing four registration points common to the 1937 aerial photo in Figure 34 .....................................................97 Figure 36. The 1966 aerial photo of the White River in Indiana with the 1937 bankline tracing and registration points..........................................................................................97 Figure 37. Meander loop evolution and classification scheme proposed by Brice............................98 Figure 38. Circles that define the average outer banklines from the 1937 aerial photo of the White River site in Indiana ..........................................................................99 Figure 39. Depiction of the bends from 1937 (dotted line) and 1966 (dashed line) outer banklines as defined by best-fit circles ............................................................................99 Figure 40. Depiction of the bends from the 1937 (dotted line) and 1966 (dashed line) outer banklines, as defined by best-fit circles, and the predicted location and radius of the 1998 outer bankline circle (solid line) .................................................................100 Figure 41. Aerial photo of the White River in 1966 showing the actual 1937 banklines (white) and the predicted 1998 bankline positions (black) ............................................101

vii Figure 42. Aerial photograph of the White River site in Indiana in 1998 comparing the predicted bankline positions with the actual banklines..................................................102 Figure 43. Channel migration comparison for the Tombigbee River near Amory, MS ..................108 Figure 44. Predicted versus actual bank migration direction...........................................................109 Figure 45. Predicted versus actual bend radius and bank migration magnitude ..............................110 Figure 46. Error in bank migration as a percent of channel width (incremental percent)................111 Figure 47. Error in bank migration relative to channel width (cumulative percent)........................112 Figure 48. Change in Radius of Curvature versus Radius of Curvature/Width (C Sites)................113 Figure 49. Change in Radius of Curvature versus Radius of Curvature/Width (C Sites grouped data).....................................................................................................114 Figure 50. Bank Erosion Rate versus Channel Width .....................................................................115 Figure 51. Change in Channel Width at C Sites ..............................................................................116 Figure 52. Beta test site on the Sacramento River at Sidds Landing, California .............................118 Figure 53. Banklines and circles inscribed on outer bankline positions for a hypothetical channel at 3 different years ............................................................................................119 Figure 54. Diagram defining the outer bank radius of curvature in Years 1, 2, and 3.....................119 Figure 55. Beta test site on the Minnesota River at Judson, Minnesota ..........................................120 Figure 56. Comparison of bend radius measurements .....................................................................123 Figure 57. Comparison of migration distance measurements ..........................................................123 Figure 58. Comparison of ArcView and manual techniques for radius and migration....................124

viii LIST OF TABLES Table 1. Controls on Meander Morphology and Variability of Change............................................31 Table 2. Apex Movement Statistical Characteristics .........................................................................58 Table 3. Rates of Extension and Translation .....................................................................................62 Table 4. Years to Migrate One Channel Width .................................................................................63 Table 5. Sources of Contemporary and Historical Aerial Photographs and Maps ............................67 Table 6. Classification of Alluvial Channels .....................................................................................88 Table 7. Classification of Channel-Reach Morphology in Mountain Drainage Basins of the Pacific Northwest................................................................................................................93 Table 8. Task 8 State Beta Test Participants....................................................................................117