Thesis Instream Flow Methodologies: an Evaluation of the Tennant Method for Higher Gradient Streams in the National Forest System Lands in the Western U.s

................................................................................................................................................iii 1.0 Background...............................................................................................................................1 1.1 Instream Flow Requirements.............................................................................................2 1.2 Tennant Method ..................................................................................................................4 1.3 Wetted Perimeter Method..................................................................................................7 1.4 PHABSIM (Physical Habitat Simulation System)...........................................................9 1.5 Previous Instream Flow Methodology Analyses...........................................................11 2.0 Purpose and Objectives ........................................................................................................15 3.0 Data and Methodology .........................................................................................................18 3.1 Data Collection ..................................................................................................................18 3.2 Data Description ...............................................................................................................20 3.2.1 Data Sources ..............................................................................................................24 3.3 Tennant Method Calculations .........................................................................................26 3.3.1 WinXSPro: A Channel Cross-Section Analyzer ..................................................29 3.4 Methodology Comparisons..............................................................................................33 3.4.1 Wetted Perimeter Comparison................................................................................34 3.4.2 PHABSIM Comparison ...........................................................................................36 3.5 Regional Analyses ..............................................................................................................39 3.5.1 Stream Types..............................................................................................................39 3.5.2 Ecoregions..................................................................................................................40 3.5.3 States ...........................................................................................................................42 3.5.4 Hydro-Climatic Data ................................................................................................42 3.6 Nebraska Data Comparison.............................................................................................42 4.0 Results .....................................................................................................................................43 4.1 Tennant Method Calculations .........................................................................................43 4.1.1 Depth Calculations....................................................................................................44 4.1.2 Velocity Calculations.................................................................................................47 4.1.3 Width Calculations ....................................................................................................48 4.2 Methodology Comparisons..............................................................................................48 4.2.1 Wetted Perimeter Method........................................................................................48