Analysis of equivalent widths of alluvial channels and application for instream habitat in the Rio Grande

Abstract

Rivers are natural systems that adjust to variable water and sediment discharges. Channels with spatial variability in width that are managed to maintain constant widths over a period of time are able to transport the same water and sediment discharges by adjusting the bed slope. Methods developed to de ne equilibrium hydraulic geometry characteristics of alluvial channels are limited to steady state input variables.This dissertation examines how the channel slopes adjust in sequential reaches with different widths to achieve continuity of steady and unsteady water and sediment discharges. The four objectives of this dissertation are: 1) to develop analytical relationships between equilibrium slope and width or width-depth ratio under steady water and sediment discharges; 2) to develop a transient numerical model for constant input variables to simulate the changes in channel slope with time; (3) to develop a transient numerical model for unsteady water and sediment discharges to simulate the transient solution of channel slope; and (4) to apply the model to the middle Rio Grande and integrate the results in the evaluation of potential fish habitat restoration activities.

Citation

Leon, Claudia A. 2003. Analysis of equivalent widths of alluvial channels and application for instream habitat in the Rio Grande. Fort Collins, CO: Colorado State University. 283 p. Dissertation.