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Simulation of Flow, Sediment Transport, and Sediment Mobility of the Lower Coeur D’Alene River, Idaho

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Simulation of Flow, Sediment Transport, and Sediment Mobility of the Lower Coeur D’Alene River, Idaho Prepared in cooperation with the Idaho Department of Environmental Quality, Basin Environmental Improvement Commission, and the U.S. Environmental Protection Agency Simulation of Flow, Sediment Transport, and Sediment Mobility of the Lower Coeur d’Alene River, Idaho Scientific Investigations Report 2008–5093 U.S. Department of the Interior U.S. Geological Survey Simulation of Flow, Sediment Transport, and Sediment Mobility of the Lower Coeur d’Alene River, Idaho By Charles Berenbrock and Andrew W. Tranmer Prepared in cooperation with the Idaho Department of Environmental Quality, Basin Environmental Improvement Commission, and the U.S. Environmental Protection Agency Scientific Investigations Report 2008–5093 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior DIRK KEMPTHORNE, Secretary U.S. Geological Survey Mark D. Myers, Director U.S. Geological Survey, Reston, Virginia: 2008 For product and ordering information: World Wide Web: http://www.usgs.gov/pubprod Telephone: 1-888-ASK-USGS For more information on the USGS--the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment: World Wide Web: http://www.usgs.gov Telephone: 1-888-ASK-USGS Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this report. Suggested citation: Berenbrock, Charles, and Tranmer, A.W., 2008, Simulation of flow, sediment transport, and sediment mobility of the Lower Coeur d’Alene River, Idaho: U.S. Geological Survey Scientific Investigations Report 2008–5093, 164 p. iii Contents Abstract ...........................................................................................................................................................1 Introduction.....................................................................................................................................................2 Purpose and Scope ..............................................................................................................................5 Description of Study Reach ................................................................................................................5 Previous Investigations.................................................................................................................................7 FEMA Model (1981) ...............................................................................................................................7 USGS Model (1992) ...............................................................................................................................7 University of Idaho Model (2004) ........................................................................................................7 Golder Associates Model (2005) ........................................................................................................8 Reach Characterization ................................................................................................................................8 Flow Types ..............................................................................................................................................8 River Stage .............................................................................................................................................9 River Discharge ...................................................................................................................................13 Channel Cross Sections .....................................................................................................................13 Streambed Samples ...........................................................................................................................16 Sediment-Transport Characteristics ........................................................................................................18 Suspended Sediment .........................................................................................................................18 Total Sediment Discharge .................................................................................................................18 Numerical Modeling ....................................................................................................................................22 HEC-6 Model Implementation ...........................................................................................................22 Model Cross Sections ...............................................................................................................23 Model Boundaries .....................................................................................................................23 Model Calibration ......................................................................................................................23 Simulation of Erosion, Deposition, and Sediment Transport under Varying Conditions ......................................................................................................................27 Dredging in Dudley Reach ...............................................................................................27 Reduction in Sediment Discharge Input .......................................................................29 Model Limitations.......................................................................................................................30 FASTMECH Model Implementation .................................................................................................30 Model Grid and Bathymetric Interpolation ............................................................................31 Model Boundaries .....................................................................................................................31 Model Calibration ......................................................................................................................33 Results of Calibration Simulations ..........................................................................................34 Flow Depth .........................................................................................................................34 Flow Velocity ......................................................................................................................34 Shear-Stress ......................................................................................................................42 Sediment Mobility .............................................................................................................42 Model Limitations................................................................................................................................46 Summary........................................................................................................................................................47 Acknowledgments .......................................................................................................................................48 References Cited..........................................................................................................................................49 Glossary .........................................................................................................................................................53 iv Contents—Continued Appendix A. Locations of Cross Sections on the Coeur d’ Alene River, Idaho ..............................55 Appendix B. Particle-Size Analysis of Streambed Samples in the Dudley Reach, Coeur d’Alene River, Idaho ...........................................................................................................59 Appendix C. Listing of HEC-6 Model Input File for 1999 .....................................................................69 Appendix D. Grain Shear Stress, Largest Mobilized Particle, and Particle Classification for FASTMECH simulations 1 through 5, Coeur d'Alene River, Idaho ..................................161 Figures Figure 1. Map showing location of study area and U.S. Geological Survey gaging stations, Coeur d’Alene River basin, Idaho ……………………………………… 3 Figure 2. Map showing location of study area, U.S. Geological Survey gaging stations, river miles, and lateral lakes, Coeur d’Alene River basin, Idaho ………………… 4 Figure 3. Diagram showing water-surface curves along a constant, uniform, mild-sloped channel …………………………………………………………………………… 8 Figure 4. Graph showing simulated water-surface curves for a discharge of 25,000 cubic feet per second in the lower Coeur d’Alene River, Idaho …………………… 9 Figure 5. Graph showing daily water levels on Coeur d’Alene Lake at Coeur d’Alene (12415500), Idaho ………………………………………………………………… 10 Figure 6. Graph showing water-surface elevations and discharge at selected gaging stations on the Coeur d’Alene River and Coeur d’Alene Lake, 1994–2000 ………… 11 Figure 7. Graphs showing relation between water-surface elevation for Coeur d’Alene Lake, and the Harrison and Rose Lake gaging stations in the study reach, Coeur d’Alene River, Idaho ……………………………………………………… 12 Figure 8. Graphs showing discharge at selected gaging stations on the Coeur d’Alene River, Idaho ………………………………………………………………………
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