1 STREAM CLASSIFICATION & STREAM CLASSIFICATION & RIVER ASSESSMENT RIVER ASSESSMENT Seneca Creek, Monongahela National Forest, West Virginia Greg Babbit Greg Babbit Graduate Research Assistant Graduate Research Assistant Dept. Forestry, Wildlife & Fisheries Dept. Forestry, Wildlife & Fisheries OBJECTIVES OBJECTIVES Introduce basic concepts of river process, Introduce basic concepts of river process, form & function form & function Introduce some common geomorphic Introduce some common geomorphic classification systems classification systems Rosgen Rosgen classification system classification system Discuss methods of morphological Discuss methods of morphological assessment assessment Fluvial Geomorphology? Fluvial Geomorphology? Geomorphology Geomorphology - The study of landscapes and their The study of landscapes and their evolution evolution Fluvial Geomorphology Fluvial Geomorphology – The study of The study of erosional erosional and and depositional processes from running water that forms depositional processes from running water that forms the landscape the landscape The term "fluvial" was derived from the Latin word The term "fluvial" was derived from the Latin word "fluvius fluvius" meaning river. " meaning river. Fluvial geomorphology examines the processes that Fluvial geomorphology examines the processes that operate in river systems and the landforms which they operate in river systems and the landforms which they ultimately create, or have created. ultimately create, or have created. - J.R. Miller J.R. Miller
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STREAM CLASSIFICATION & STREAM CLASSIFICATION & RIVER ASSESSMENTRIVER ASSESSMENT
Seneca Creek, Monongahela National Forest, West Virginia
Greg BabbitGreg BabbitGraduate Research AssistantGraduate Research AssistantDept. Forestry, Wildlife & FisheriesDept. Forestry, Wildlife & Fisheries
OBJECTIVESOBJECTIVES
Introduce basic concepts of river process, Introduce basic concepts of river process, form & functionform & functionIntroduce some common geomorphic Introduce some common geomorphic classification systemsclassification systemsRosgenRosgen classification systemclassification systemDiscuss methods of morphological Discuss methods of morphological assessmentassessment
Fluvial Geomorphology?Fluvial Geomorphology?
Geomorphology Geomorphology -- The study of landscapes and their The study of landscapes and their evolutionevolutionFluvial Geomorphology Fluvial Geomorphology –– The study of The study of erosionalerosional and and depositional processes from running water that forms depositional processes from running water that forms the landscapethe landscapeThe term "fluvial" was derived from the Latin word The term "fluvial" was derived from the Latin word ""fluviusfluvius" meaning river. " meaning river. Fluvial geomorphology examines the processes that Fluvial geomorphology examines the processes that operate in river systems and the landforms which they operate in river systems and the landforms which they ultimately create, or have created. ultimately create, or have created. -- J.R. Miller J.R. Miller
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Streams transport Streams transport water, sediment & water, sediment & energyenergy
Geographic Unit = Geographic Unit = WatershedWatershed
Physical, Biological, Physical, Biological, and Chemicaland Chemical
Stream channel shape, Stream channel shape, size, and patternsize, and pattern
Ability of a stream over time, in the present Ability of a stream over time, in the present climate, to effectively transport the flows and climate, to effectively transport the flows and sediment from its watershed while neither sediment from its watershed while neither aggrading or degrading and maintaining a stable aggrading or degrading and maintaining a stable dimension, pattern and profile. dimension, pattern and profile. –– RosgenRosgen (1996)(1996)For instance, during droughts there is an For instance, during droughts there is an increase in change to the river due to climatic increase in change to the river due to climatic change, vegetative influence, high intensity change, vegetative influence, high intensity convective thunder stormsconvective thunder storms
CONTINUITY EQUATIONCONTINUITY EQUATION
DISCHARGE (cfs) Q = V x AV = Velocity (ft/s)A = Cross-sectional Area (ft2)
V = related to slope, channel shape & boundary roughness
(FISRWG 1998)
CALCULATING DISCHARGECALCULATING DISCHARGE
MANNING’S EQUATION
Q = 1.49 R2/3 S1/2
n
R = Hydraulic RadiusS = Water Surface Slopen = Manning’s Roughness
Coefficient
(FISRWG 1998)
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GEOMORPHIC PROCESSESGEOMORPHIC PROCESSES
3 PRIMARY PROCESSES INVOLVED WITH 3 PRIMARY PROCESSES INVOLVED WITH FLOWING WATER:FLOWING WATER:
ErosionErosion –– detachment of soil particlesdetachment of soil particles
Sediment transportSediment transport –– movement of eroded particles movement of eroded particles in flowing waterin flowing water
Sediment depositionSediment deposition –– settling of eroded particles settling of eroded particles to the bottom of a to the bottom of a waterbodywaterbody or left behind in the or left behind in the stream bed as substrate or point bar stream bed as substrate or point bar ((SchummSchumm, 1977), 1977)
RIVER FORM ORRIVER FORM ORMORPHOLOGICAL CONDITIONMORPHOLOGICAL CONDITION
Fluvial Fluvial geomorphologistsgeomorphologists refer to effective discharge as therefer to effective discharge as the
stream flow that most efficiently moves sediment through a stream flow that most efficiently moves sediment through a
stream channelstream channel
(Rosgen 1996)
BANKFULL DISCHARGEBANKFULL DISCHARGE
““Bankfull stage corresponds to the discharge at Bankfull stage corresponds to the discharge at which channel maintenance is the most effective, which channel maintenance is the most effective, that is, the discharge at which moving sediment, that is, the discharge at which moving sediment, forming or removing bars, forming or changing forming or removing bars, forming or changing bends and meanders, and generally doing work bends and meanders, and generally doing work that results in the average morphological that results in the average morphological characteristics of channels.characteristics of channels.”” –– Dunne & LeopoldDunne & Leopold
The flow that fills the active channel and begins to The flow that fills the active channel and begins to spread onto the floodplainspread onto the floodplain
BANKFULL FLOW CONTINUEDBANKFULL FLOW CONTINUED
Represents the break between channel processes and Represents the break between channel processes and floodplain processesfloodplain processesAverage bankfull discharge recurrence interval 1.5Average bankfull discharge recurrence interval 1.5--yearsyearsAssumed to equal the dominant discharge and effective Assumed to equal the dominant discharge and effective dischargedischargeBankfull stage is identified from geomorphic features in the Bankfull stage is identified from geomorphic features in the fieldfieldBankfull discharge is the stream flow that is found to Bankfull discharge is the stream flow that is found to govern channel shape and formgovern channel shape and formEffective discharge of sediment is highly correlated with Effective discharge of sediment is highly correlated with bankfull dischargebankfull discharge
Davis (1899) youthful, mature and old age stage of adjustmentDavis (1899) youthful, mature and old age stage of adjustmentStrahlerStrahler’’ss (1957) Stream order(1957) Stream orderLeopold & WolmanLeopold & Wolman’’s (1957) early work on natural alluvial channel s (1957) early work on natural alluvial channel patternspatternsSchummSchumm’’ss (1977) Fluvial System(1977) Fluvial SystemKellerhalsKellerhals et al. et al. (1976)(1976) channel pattern, islands, bars, channel pattern, islands, bars, bedformbedform & & lateral activity lateral activity Simon & Simon & HuppHupp (1986) channel evolution model in W. TN(1986) channel evolution model in W. TNMontgomery & BuffingtonMontgomery & Buffington’’s (1997) expansion in mountainous s (1997) expansion in mountainous regionsregionsRosgenRosgen (1994) classification of natural rivers(1994) classification of natural rivers
STRAHLERSTRAHLER’’S STREAM ORDERS STREAM ORDER
(Strahler 1957; FISRWG 1998)
SCHUMMSCHUMM’’S FLUVIAL SYSTEMS FLUVIAL SYSTEM
(Schumm 1977; FISRWG 1998)
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CHANNEL EVOLUTION CHANNEL EVOLUTION MODEL (CEM)MODEL (CEM)
(Simon 1989; FISRWG 1998)
SIMONSIMON’’S CHANNEL S CHANNEL EVOLUTION STAGESEVOLUTION STAGES
Purpose: predict river behavior from Purpose: predict river behavior from morphological descriptionmorphological descriptionExtrapolate relationships between different Extrapolate relationships between different stream typesstream typesOrganize and stratify various empirical relationsOrganize and stratify various empirical relationsProvide a morphological stratification for Provide a morphological stratification for companion inventoriescompanion inventoriesProvide a consistent frame of reference for Provide a consistent frame of reference for communicationcommunication
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EXAMPLES OF VALLEY TYPEEXAMPLES OF VALLEY TYPE
(Rosgen 1996)
BROAD LEVEL OF STREAM BROAD LEVEL OF STREAM TYPE DELINEATIONTYPE DELINEATION
(Rosgen 1996)
ROSGEN STREAM TYPESROSGEN STREAM TYPES
(Rosgen 1996)
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CROSS SECTION OF STREAM CROSS SECTION OF STREAM TYPESTYPES
(Rosgen 1996)
CLASSIFICATION KEY FOR CLASSIFICATION KEY FOR NATURAL RIVERSNATURAL RIVERS
A graphical method of illustrating a stream A graphical method of illustrating a stream channelchannel’’s bankfull hydraulic geometry as a s bankfull hydraulic geometry as a function of basin drainage area within a specific function of basin drainage area within a specific ecoregionecoregion and/or hydroand/or hydro--physiographic provincephysiographic provinceBreakdown of regions provides a more accurate Breakdown of regions provides a more accurate depiction of the basin variables affecting stream depiction of the basin variables affecting stream morphology morphology
Depth = 1.76(DA)Depth = 1.76(DA) .256.256
Width = 18.51(DA)Width = 18.51(DA).444.444
Area = 32.48(DA)Area = 32.48(DA) .701.701
Q = 150.06(DA)Q = 150.06(DA) .75.75
SOUTHWESTERN APPALACHIANS OF SOUTHWESTERN APPALACHIANS OF TENNESSEE REGIONAL CURVESTENNESSEE REGIONAL CURVES
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BANKFULL DISCHARGE VS DABANKFULL DISCHARGE VS DA
Rock Creek Riffle Cross SectionGround Points Bankfull
River Name: CLINCH RIVERRiver Name: CLINCH RIVERReach Name: Beaver Creek Reach Name: Beaver Creek TribTrib <<---- This is not a Reference ReachThis is not a Reference ReachDrainage Area: 0.43 sq miDrainage Area: 0.43 sq miState: TennesseeState: TennesseeCounty: KnoxCounty: KnoxLatitude: 0Latitude: 0Longitude: 0Longitude: 0Survey Date: 04/20/05Survey Date: 04/20/05