Assistant Professor McEnery has received a one-year $99,764 research grant to conduct Nonlinear Three Dimensional Finite Element Analyses of the Brazos River in Fort Bend County, Texas. This project will develop a detailed predictive model of decadal changes in channel morphology along the Brazos River downstream of the Allens Creek confluence. Behavior of the channel geometry and bar formation will be examined with a coupled approach. Hydraulic modeling of sediment transport will be combined with stratigraphic assessment to produce a geomorphic analysis of changing channel conditions over both a near term and extended temporal range.

State-of-the-art three dimensional finite element analyses will be developed using the hydraulic modeling program ADH (Adaptive Hydraulics, U.S. Army Corps of Engineers, 2010). The program uses a dynamically adaptive finite element mesh to solve velocity field calculations for channel geometries including structures and improvements such as fish passages (Gambucci, 2009). In addition to solution of the St. Venant equations for flow, a computational scheme has also been developed to model cohesionless sediment transport (Brown and Tate 2009). ADH includes provisions to estimate bed movement and reconfiguration in movable bed systems. A substrate map and data related to bed and bank material and sediment input to the reach will be created from data collected in the field. Results of the ADH hydraulic model using 2001 bathymetric data will then be used together with the field data to predict how the 2001 physical channel and habitat would be expected to change over time. Predictions of potential change will be made in a qualitative sense based on hydraulic flow patterns visible in the hydraulic model output at various flow rates. In addition, the ability of the ADH model to predict channel change will be tested by running the model in combination with the hydrologic record available from USGS gage data for the period December 2001 to July 2011.