Big Cypress/Caddo Big Cypress/Caddo WatershedWatershed

Geomorphic ClassificationGeomorphic Classification

Ryan SmithRyan Smith

The Nature Conservancy of The Nature Conservancy of TexasTexas

Utility of River ClassificationUtility of River Classification

Understand watershed context of the Understand watershed context of the riverriver

Understand normal channel, habitat, Understand normal channel, habitat, and biological characteristicsand biological characteristics

Understand impacts on natural Understand impacts on natural characteristicscharacteristics

Selection of reaches for studies of Selection of reaches for studies of habitat, water quality, riparian, etc habitat, water quality, riparian, etc

River StylesRiver Styles

Brierly and Fryirs 2000Brierly and Fryirs 2000 Developed in AustraliaDeveloped in Australia Selected by TCEQ, TPWD, and TWDB for Selected by TCEQ, TPWD, and TWDB for

Texas Instream Flows ProgramTexas Instream Flows Program Meets recommendations of NAS reviewMeets recommendations of NAS review

Physical basisPhysical basis Channel morphologyChannel morphology Hierarchical structureHierarchical structure Physiographic/hydrologic settingPhysiographic/hydrologic setting Floodplain and riparian zoneFloodplain and riparian zone

Stage 1 Data Compilation (description and mapping) • Derive watershed boundary conditions • Determine landscape units • Assess river character

Stage 2 Data Analysis • Define and interpret River Styles • Explain contemporary character/behavior

• Assess river history

Stage 3 Predict future river structure

Stage 4 Prioritize watershed management issues

Stage 5 Identify target conditions for river

Stages of a River Styles Stages of a River Styles ProcedureProcedure

River Styles HierarchyWatershed

Watershed area determined by drainage divide. Determines the boundary conditions within which rivers operate.

Geomorphic Unit Instream and floodplain landforms (pools, bars, levees, backwaters, etc.) that reflect distinct form-process associations.

River StyleLength of channel with a characteristic assemblage of geomorphic units.

Landscape Unit Topographic unit determined on the basis of local relief, valley slope and morphology. Defines the valley-setting.

Hydraulic Unit Uniform patches of flow and substrate material within a geomorphic unit.

Microhabitat Individual elements (e.g., logs, rocks, gravel patches) within a stream.

GIS Data AtlasGIS Data Atlas TNC NFWF grantTNC NFWF grant

GIS data atlas for the Caddo Lake watershed GIS data atlas for the Caddo Lake watershed West Gulf Coastal Plain aquatic conservation West Gulf Coastal Plain aquatic conservation

prioritiespriorities Considering development of data for River Considering development of data for River

Styles Stage 1 analysis of Big Cypress Styles Stage 1 analysis of Big Cypress Bayou watershedBayou watershed

TNC aquatic ecosystems classificationTNC aquatic ecosystems classification Many river characteristics calculated in a GISMany river characteristics calculated in a GIS Consider data’s usefulness for River StylesConsider data’s usefulness for River Styles Consider developing additional data in the data Consider developing additional data in the data

atlas workatlas work

TNC Aquatic Ecosystems TNC Aquatic Ecosystems ClassificationClassification

Mapped in 1:100K Mapped in 1:100K National National Hydrography Hydrography DatasetDataset

Variables: Variables: Watershed areaWatershed area GradientGradient Contributing area Contributing area

geologygeology Longitudinal Longitudinal

connectivityconnectivity

River Styles for Big Cypress River Styles for Big Cypress Watershed?Watershed?

Undertake a River Styles analysis for Big Cypress Undertake a River Styles analysis for Big Cypress Bayou watershed?Bayou watershed? Value added?Value added? Relationship to other studies (e.g., channel cross-Relationship to other studies (e.g., channel cross-

sections)?sections)? Relationship to characterization, classification of Relationship to characterization, classification of

hydrologic regimehydrologic regime What are the most important aspects of river What are the most important aspects of river

characteristics in the area that would need to be characteristics in the area that would need to be included in the development of River Styles here?included in the development of River Styles here? Watershed characteristics?Watershed characteristics? Landscape, geomorphic unit characteristics?Landscape, geomorphic unit characteristics?

What data are needed?What data are needed? Is TNC’s data useful? What else needed?Is TNC’s data useful? What else needed? Limitation of geomorphology expertiseLimitation of geomorphology expertise

River Styles: Australian Example

Watershed Namoi River Basin, New South Wales

Kilometers0 10050 7525

Lower Namoi Sub-basin

Middle Namoi Sub-basin

Mooki Sub-basin

Peel Sub-basin

Macdonald/ManillaSub-basin

River Styles: Australian Example

Watershed

LandscapeUnit

Namoi River Basin, New South Wales

Kilometers0 1005025

Legend – Landscape Units

Rugged metasediments

Rugged volcanics

Uplands

Pillaga outwash

Pillaga

Mid to lower Peel

Lowland plains

Liverpool plains

Channel and Valley Width

Channel Slope

Valley Cross Section

Planform

Uplands Escarpment Base of the Escarpment Rounded Foothills Lowland Plain

LandscapeUnit

River StyleHead-water

GorgeFan

Cut & Fill (Incised)

Cut & Fill (Intact)

Vertically Accreated Floodplain

ThroughputFloodout

Transfer

Floodplain Accumulation

River Styles: Australian Example

Watershed

LandscapeUnit

River Style

Kilometers0 5025

Middle NamoiSub-basin

GeomorphicUnit

HydraulicUnit

Microhabitat

Riffle

Floodplain

Run

Pool

Bar

Secondary Channel

Pool

BackwaterTrailing

Vegetation

Submerged Macrophyte

Cobbles

Large Woody Debris

BouldersSand

Leaf Pack

Rippled flow on cobbles

Smooth surface flow on cobbles

Smooth surface flow on cobbles/sand

Barely perceptible flow on sand/boulders

Barely perceptible flow on sand