This paper presents a study on sediment in Texas reservoirs and its effect on reservoir firm yield. This study examined the geographical variation of reservoir sedimentation across the state of Texas as well as the sediment distribution inside a reservoir at all depths from streambed to the top of conservation pool. Results indicate that sediment accumulates faster in lower elevations than in higher elevations in most Texas reservoirs but the opposite is true in others where significant deltaic formations exist. Reservoir capacity loss rates are estimated incrementally at different elevation levels to develop reservoir rating curves according to the vertical distribution of sediment, using the data from hydrographic surveys. Reservoir rating curves for the next 50 years are predicted, assuming a constant sedimentation rate for the prediction period. Based on the predicted rating curves, reservoir firm yields for the predicting periods can be estimated and a relationship between predicted reservoir capacity and firm yield is derived. This provides useful information for the water planning in Texas.
John Zhu– Senior Hydrologist, Texas Water Development Board, Austin, Texas
Texas Water Development Board
John Zhu is a Hydrologist at the Texas Water Development Board (TWDB) responsible for data processing, analysis, modeling, and assessment of surface water availability for water resources planning, development, and management in Texas. As a Texas-certified Professional Geoscientist (P.G.), John applies his experience in hydrological analysis and modeling using the Water Right Analysis Package (WRAP) water accounting model to compute reservoir firm yield under various scenarios (such as reservoir silting, future drought and water management strategies, etc.) in the Texas Water Availability Modeling (WAM) system. John participates in many projects including short-term reservoir storage forecast preparation, drought mapping, water condition reporting, and lake evaporation data processing, and management of TWDB reservoir database. John was educated as Hydrogeologist (B.Eng., M.Sc.) in Jilin University in China, and he earned his Ph. D. in Groundwater Hydrology from the Institute of Geology, Academia Sinica, China. Since his post-doctoral work, John has expanded his research interests into the surface water arena through research on soil water at the Institute of Geography, Academia Sinica, China; studied karst water in the Peak District, England as a Research Associate at the Manchester Metropolitan University; taught Hydrology and conducted research in karst hydrology and geomorphology as a Lecturer at the University of Papua New Guinea; and served as Chief Hydrologist at the Bureau of Water Resources, Government of Papua New Guinea. Armed with strong programming skills as a Microsoft Certified Professional (MCP), John served as an environmental hydrologist at a private company in Texas in the early 2000’s before he joined TWDB.