Sediments and sedimentary processes in Lake Houston, Texas
Matty, Jane Miller
Anderson, John B.
Master of Arts
Lake Houston is a man-made reservoir located northeast of Houston, Texas. The purpose of this investigation was to determine the nature of sediments and sedimentary processes in the lake. Cores were collected throughout the lake and sediment traps placed in strategic locations to collect suspended sediments. Samples were analyzed for grain-size, organic carbon, and a number of trace elements. The volume of the lake has been reduced by 7.8% during its first 28.5 years, with most of the sediment accumulating near the mouths of inflowing rivers. Sediment input depends primarily on the intensity of rainfall in the watershed. Sediment movement within the lake is strongly influenced by wave activity which resuspends sediments from shallow areas. The increased residence time due to resuspension allows greater decomposition of organic matter and the release of several trace elements. The principal source of both organic material and trace elements appears to be effluent from sewage treatment plants. Fluctuations in current velocities and the subsequent suspension/deposition of particles may explain variations in coliform bacteria, which occasionally pollute Lake Houston.