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<br />Executive Summary ""." ".,.......'.............., ...,....,'.............,..,.....,."....".,...,.".,...,., ,."., ".,.,..., i
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<br />I. Introduction..,...,..."."..........""..""..,....,."...."....".,...""...,.",."..,..."......".."...,."."",...3
<br />A, Purposes of Forest Service's Claims........................................................................5
<br />1. Securing Favorable Conditions of Water Flows......................................................5
<br />B. Concept of Channel Maintenance................................................,...........................6
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<br />I. Principle "".,.',......... ...'. ...............,.,.... .'.....,..........,....,....,.., ...... ...,.".... .,....".,.,.....,.,.6
<br />2. Adverse Consequences ,..............,.,...........,."...,...,.........."....,...,." '" ".." ,., ",., ".,..,...7
<br />C. Alluvial River Behavior: Concepts and Illustrations..............................................,9
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<br />I. Self-formed Channels ...,.....,....., ......,....,.....", ,................"....,.......................,..,...,... 9
<br />2. Channel Processes.........,..,......., ...............,.. ..........., ,..............,.,.,.....,...,.,..".,...,...,,1 0
<br />3, Features of Alluvial Channels,............................................................................... 12
<br />II, Channel Maintenance Claim Sites and Fluvial Process Study Sites.......................... 15
<br />A. Claim Site Selection and Criteria........................................................................... 15
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<br />I, Claim Sites.................................................................,...........................................15
<br />2. Claim Site Selection.....................................................,...........................,.............16
<br />3, Fluvial Process Study Sites.................................................................................... 16
<br />B, Geologic and Hydrologic Setting of the Claim Sites and Study Sites...................18
<br />III. Information Used to Develop and Support the Channel Maintenance Claims..........21
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<br />A. Streamflow Records ......,....,..,..,..,."..........,.................,'........ .........".,..............."...21
<br />I. Sources of Data ....,........,.......,..,..,..........,...."................,..............,.,..,...,.,.........,....23
<br />2, Flow Extension ,. .....,.....,.,...,.,...,.................". .............,...".............".,....................25
<br />B. Sediment Data and Analysis ..................................................................................27
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<br />I. Sediment Data ,.".,..' ...............,........." .............,.,..............,.,..............,.,..............,...27
<br />2. Sampling Equipment and Procedures ....................................................................27
<br />3, Laboratory Analysis ...,......................, .......,.......,..............,.................,......,..........,,30
<br />C. Development of Bedload vs, Streamflow Relationships .......................................36
<br />I. Alternative Models Investigated ........ .............,......,.,.........,...'.,........., ,..,...........,.,.40
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<br />a) Transformations ,.... ..............,..,...................,........,...'............,.,.,............,.........,.40
<br />b) Subtractive Constant ("initiation of motion") ................................................40 '
<br />c) Separation by Conditions ...................................................................................41
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<br />(I) By year: ......., ".,.... ........... ..,.,............ ."......................,................,.......,........41
<br />(2) Other categories:..................,.,.....,.....,..........,.,............,....,.....,..,........,.,...... 4 5
<br />2. Extrapolation...."..,......,.........,................,......,....,.,........""...........",..,...........,.,.,....4 5
<br />D, Channel Geometry Data and Analysis...................................................................48
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<br />E. Channel Substrate ..........................,............ ,..................................".............,.,..,...51
<br />1. Other Site Data and Analysis......................................................,..........,................55
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<br />(I) Painted Rocks ........................,...............................,.........,..........,.......,........55
<br />b) Coarsest Particles on Bars...,....,...............................,.,...............,.................,.57
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<br />IV. Site Characteristics,........................... ...................... .,...,.....,..........,.,........,.,.............,.57
<br />A. Hydrology .....".,.......................,..................................................,......................,...57
<br />B. Hydraulic Geometry ................... .........,.....................,.................,..,.....,................,60
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<br />C. Bed Materials .................................,..........,............,...............................................64
<br />D. Sediment Transport...............,.. ....,.,..........,............,..................,..........,.................66
<br />V. Channel Maintenance Claims ............,..........,...........................................................,71
<br />A. Components of the Claims....,........,....,......, ...........,.......,..........,.,........,...........,..... 71
<br />B, Procedure for Determining the Claim Initiation Discharge ................................... 72
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<br />United Slates' Expert Report DiscIosU1g MeIl1odologies for Quantification of Organic Ad Claims ConsoIidaI8d Subcase No. 63-25243
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