Award Date

2009

Degree Type

Thesis

Degree Name

Master of Science in Water Resources Management

Department

Water Resource Management

Advisor 1

Zhongbo Yu, Committee Chair

Advisor 2

Mark Stone, Committee Co-Chair

First Committee Member

Kumud Acharya

Graduate Faculty Representative

Robert Futrell

Number of Pages

89

Abstract

Vegetation encroachment reduces channel conveyance capacity below design objectives and greatly increases the risk for loss of life and property damage in the case of large flood events. Given minimal knowledge of hydraulic roughness for shrubs and woody vegetation, accurate estimation of channel capacity and water surface elevation is difficult. The ability to predict a tree's bent, reduced height in the presence of flow permits more accurate prediction of hydraulic roughness and water surface elevation.

In this study, field tests were performed to elucidate tree bending properties, which in turn served as input parameters for a numerical algorithm designed to predict tree bending for water velocities likely to be encountered during high flow events. Bending simulations reveal appreciable variability in bent tree heights, likely a manifestation of the extensive variance of plant characteristics and properties inherent in biological specimens. However, no trees were expected to bend to a height lower than approximately 30% of their nonstreamlined height, even in water moving at 2.5 m/s (~ 8 ft/s).

Keywords

Flooding; Hydraulic roughness; Hydraulics; Hydrology; Tree bending; Vegetation and flood channels; Water surface elevation

Disciplines

Earth Sciences | Environmental Sciences | Fresh Water Studies

Language

English


Share

COinS