2016 NGWA Groundwater Summit

Channel Erosion, Sediment Yields, and Water Supply: A Central Texas Case Study

Monday, April 25, 2016: 2:20 p.m.
Platte River Room (The Westin Denver Downtown)
Stephen Norair , Geology, Baylor University, Waco, TX
Peter Allen, PhD , Geology, Baylor University, Waco, TX
Joseph White, PhD , Baylor University, Waco, TX

Water demand in Central Texas is expected to rise significantly due to a projected 76% population increase by 2060. Investigations of groundwater and surface water are increasingly important for decision makers that need to balance water supply with sustainability. For surface water sources (e.g., lakes, rivers), two factors considered in determination of sustainability are: (1) upstream channel erosion rates, and (2) accumulation rates of sediment downstream.  In this study, a combination of dendrogeomorphic, submerged jet testing, laser scanning, and SWAT-DEG modeling techniques are integrated to determine past erosion rates and predict future channel behavior for two stream channels in Central Texas. Dendrogeomorphology estimates past erosion rates from trees with exposed roots due to anatomical changes that occur after roots are uncovered by channel erosion. This method is valuable because historical erosion data can be gathered in previously unstudied locations. The erodibility of channel soils are determined using the submerged jet test. By subjecting an undisturbed sediment core from a stream channel to a jet of water at a known velocity, its resistance to scour erosion can be determined. A fabricated laser scanner was also developed for this project. This device uses three relatively inexpensive range-finder lasers to generate a centimeter-resolution channel cross sections. It also provides a labor-efficient method to monitor future channel morphology changes. These data can then be used to calibrate and validate SWAT-DEG, a channel degradation model that predicts the amount of stream bank erosion occurring within a reach. By integrating these measurement, monitoring, and prediction techniques channel change and sediment yields can be calculated to determine how much water is available within lake and reservoir sources, thereby giving water managers the information needed to determine how to sustainably utilize ground water resources.

Stephen Norair, Geology, Baylor University, Waco, TX
Stephen Norair is currently a second year Master's student at Baylor University studying hydrology. After achieving a Bachelor’s degree in geology from Indiana University of Pennsylvania, where his undergraduate research focused on climate change and stream discharge patterns, he went on to work in both the mortgage banking industry and petroleum industry before continuing his formal education. During this time he has participated in GIS short courses, safety and hazard management workshops, and volunteered his time at groundwater conservation districts. Stephen hopes to publish his Master’s research and continue expanding his expertise in industry after graduating in 2016.

Peter Allen, PhD, Geology, Baylor University, Waco, TX
Dr. Peter Allen is professor of geology at Baylor University. His research interests include: � Impact of urbanization on stream channels; erosion degradation and aggradation of streams. � Stream-groundwater interactions and water budget models. � Recharge mechanisms and bypass flow in clay shale terrain. � Field techniques for assessment of geological processes as sedimentation and erosion.

Joseph White, PhD, Baylor University, Waco, TX
Dr. Joseph D. White received both undergraduate and Master's degrees from the Texas Christian University in Biology and is a certified for secondary educator for the state of Texas. He was awarded the doctoral degree in 1996 from the University of Montana's School of Forestry for his research on global climate change impacts on alpine environments derived from satellite information and computer modeling. In 1997, Dr. White received a post-doctoral appointment from Landcare Research in New Zealand to assess national carbon storage in indigenous forests as part of the New Zealand's international commitment to the Kyoto Protocol for climate change mitigation. Following this post-doctoral position, he joined the faculty of the Department of Biology as Assistant Professor at Baylor University. He, along with other colleagues in Biology, Geology, and Environmental Studies, formed The Institute for Ecological, Earth, and Environmental Sciences (TIE3S) at Baylor in 2005 to foster interdisciplinary work, research, and education on global environmental issues. He currently holds the positions of Professor of Biology and Director/Graduate Program Director of TIE3S. His present research topics include watershed and reservoir nutrient dynamics, fire risk in conservation lands, and woody plant-water relationships. As a life-long student of the natural world, his deepest passion is to understand how things work at their most fundamental level following in the words of St. Thomas Aquinas, "No one can love something unknown."