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|Title:||Grays Harbor Estuary, Washington. Report 2, North jetty study : hydraulic model investigation|
|Authors:||United States. Army. Corps of Engineers. Seattle District.|
Brogdon, Noble J.
Grays Harbor estuary
|Publisher:||Hydraulics Laboratory (U.S.)|
Engineer Research and Development Center (U.S.)
|Series/Report no.:||Technical report (U.S. Army Engineer Waterways Experiment Station) ; H-72-2 rept.2.|
Abstract: The existing, comprehensive fixed-bed model of the Grays Harbor estuary was used to determine the effects of several plans for rehabilitation of the north jetty. Model tests were conducted to determine the effects on hydraulic, salinity, shoaling, and dye dispersion characteristics. Test results consist of current velocity, tidal height, and salinity measurements; shoaling patterns in the entrance area; dye dispersion characteristics; and photographs of surface current patterns. Model test results indicated that a 650-ft extension to the north jetty (plan 2) would cause only insignificant local changes in current velocities and patterns in the entrance area. A 1500-ft extension to the north jetty (plan 1) would not cause significant changes in tidal elevations, current velocities, current patterns, or the extent of saltwater intrusion; but vertical mixing would be somewhat increased in the main channel of the entrance area, somewhat decreased in the northern half of the entrance area, and slightly decreased upstream from Aberdeen. Shoaling would increase in the existing, naturally deep entrance navigation channel. It is not known if this would require maintenance dredging, but it should reduce the possibility of undermining the south jetty. Flushing of pollutants from an upstream source would be decreased, while that for an entrance area source would be increased. It does not appear that the stability of Point Chehalis would be significantly affected. The central portion of the estuary flushes at a slower rate than other parts of the estuary for both existing and proposed north jetty extension conditions.
|Appears in Collections:||Technical Report|