Sediment Transport Modeling

For large basins or more complex sites, Dynamic Solutions provides sediment transport computer modeling services. Sediment transport models predict the movement of sediments in water bodies. The processes simulated include sediment resuspension (scour), deposition and transport of both cohesive and non-cohesive sediments. The sediment transport models are driven by hydrodynamic forcing from an integrated hydrodynamic model or hydrodynamic input data from field measurements. Sediment transport models are critical components of natural resource damage assessments (NRDA), navigation studies, contaminant transport studies and evaluations of the effectiveness of BMPs. Some example sediment transport modeling studies completed by the Dynamic Solutions staff and associates include:

Upper Mississippi and Illinois Waterway Sedimentation Study, USACE St. Louis District. DSLLC associates performed an analysis of bank-line sediment erosion by vessel-induced waves in the Upper Miss-Illinois Waterway. As part of an environmental evaluation of increased traffic on the waterway, a simple calculation method for simulating suspended sediment concentration increases in the waterway due to the passage of a tow was developed. The method was then used to predict sediment suspension under future traffic conditions as a part of the overall study.

Tennessee Tombigbee Waterway Navigation Study. Dynamic Solutions associates were part of a team that conducted a hydraulic and sedimentation study and developed numerical models to devise solutions to sediment erosion and deposition problems in ports of the Tennessee-Tombigbee Waterway. Sediment flows into the waterway via local streams and deposits, and then is resuspended by commercial vessel propwash resulting in sediment accumulations in port facilities.

Sediment Flume (Sedflume) Study, Weston Solutions. DSLLC designed, performed oversight and evaluated the data from a sediment (Sedflume) study on a section of the Housatonic River in western Massachusetts. Representatives from the USACE ERDC and Sandia National Laboratory mobilized a mobile Sedflume apparatus to the location and performed an analysis of sediment cores collected from the site. Data from the study was utilized to bound sediment critical shear values for use in a 3-dimensional numerical model of the site.

Suspended Sediment Modeling of the Cumberland Reservoir, Kentucky, USACE Nashville District. Lake Cumberland located on the Cumberland River in south central Kentucky experiences influxes of high concentrations of suspended sediment into the upper portions of the lake during periods of heavy rainfall and runoff into the reservoir and tributary streams. These sediments originate both from the tributary streambeds and the areas of the watershed that have been strip-mined. Subsurface plumes of high concentrations of suspended sediment are formed and often move downstream where they are discharged through the hydroelectric turbines. DSLLC staff applied the USACE model CE-QUAL-W2 to the reservoir using the suspended solids algorithm in CE-QUAL-W2 to simulate suspended sediments. The major purposes of the modeling effort were to evaluate the suitability of CE-QUAL-W2 for simulating suspended sediment dynamics in Lake Cumberland, and to improve understanding of the suspended sediment dynamics.

Test Reach Flow and Sediment Flux Analysis, MA. Dynamic Solutions designed and implemented a 2-year flow, discharge and sedimentation study on a section of the Housatonic River to estimate annual storm discharges and bank-related sediment contributions to the river during large storm events. The study included extensive instrument deployment, data collection/management, data analysis, database development and utilization of large databases. Fieldwork included deployment of sediment toe pins, water sampling equipment for TSS and sediment bedload sample collection and deployment of flow meters and staff gages for collection of discharge and water level measurements. Hydrologic data was also taken from existing USGS gages and databases for the years 1990-2003. Data was collected at several locations along the river for 10 storm events.