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https://hdl.handle.net/11681/47655| Title: | Aquatic disposal field investigations, Columbia River disposal site, Oregon : Appendix A, investigation of the hydraulic regime and physical nature of the bottom sedimentation |
| Authors: | Sternberg, Richard W., 1934- Creager, Joe S. Glassley, William Johnson, Janice |
| Keywords: | Aquatic ecology Sedimentation and deposition Sediment transport Dredging Dredging spoil Dredged material Columbia River Dredged Material Research Program (U.S.) |
| Publisher: | U.S. Army Engineer Waterways Experiment Station |
| Series/Report no.: | Technical Report (Dredged Material Research Program (U.S.)) ; no. Technical Report D-77-30; Appendix A |
| Abstract: | A two-part study was conducted in a region seaward of the Columbia River where disposal of large quantities of dredged material has occurred over the last several decades. The first part included repeated bathymetric surveys and sampling for distribution and seasonal variations of sediment texture and mineralogy throughout the study area, and especially at designated disposal sites. Near-bottom hydraulic conditions (waves, tides, currents, turbidity) were also measured at several sites and during all seasons. The second part was related to an experiment in which 600,000 cu yd of material dredged from the Columbia River estuary were dumped at a specially designated site, which was monitored before, during, and after disposal. The objectives of the sedimentological aspects of the study were to identify and map all deposits of dredged material and to recognize seasonal and long-term changes. The objectives of the hydraulic aspects were to document the 'ambient' near-bottom conditions, and their effect on the deposit at the experimental site. Sedimentological data show that deposits of dredged material can be identified relative to the surrounding sediments. They tend to maintain their identity for many years, and disperse northward at approximately 0.3 nmi per year. At the experimental disposal site the volume of the bottom deposit was 61% of the total material dumped. Calculations of bedload transport rates, based on seasonal measurements of bottom currents, suggest that 830 cu yd of material (0.2% of the total) spread northward from the site about 0.25 nmi per year. This is similar to the rates determined by the sedimentological techniques. The coherent and complementary nature of the results emphasizes the value of combining both descriptive sedimentological techniques and measurements of oceanic processes for monitoring and predicting the fate of dredged material. |
| Description: | Technical Report |
| Gov't Doc #: | Technical Report D-77-30; Appendix A |
| Rights: | Approved for Public Release; Distribution is Unlimited |
| URI: | https://hdl.handle.net/11681/47655 |
| Appears in Collections: | Technical Report |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| Technical Report D-77-30 Appendix A.pdf | 19.16 MB | Adobe PDF |  View/Open |