Effects of subsidence on stream hydraulics
Date
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
The continuing problem of subsidence in the Houston-Galveston area has raised concern about the possible adverse effects of subsidence on the hydraulic character of local streams through changes in watershed slope. Because the Houston Ship Channel is generally the center of subsidence in the area, any losses in elevation there result in decreases in the overall slope of the Armand Bayou watershed. At the upstream boundary of the watershed, the average subsidence rate between 1964 and 1973 was 4. 7 in/yr; while at the most downstream point in the watershed, the average subsidence rate was only 2. 7 in/yr during the same period. Over the entire watershed, this 2. 0 in/yr difference represents a 0. 6%/yr change in slope. Concern has centered on possible reductions in the conveyance capacity of the watershed's major north-south drainage channels resulting from sustained losses in grade. The paper reports on an investigation undertaken to attempt to characterize the effects of subsidence on the hydraulic behavior of the Armand Bayou watershed