Knowledge Core Collection:
https://hdl.handle.net/11681/42600
2024-03-29T05:24:07ZOutlet Works and Stilling Basin Ririe Dam and Reservoir, Willow Creek, Idaho : Hydraulic Model Investigation
https://hdl.handle.net/11681/47538
Title: Outlet Works and Stilling Basin Ririe Dam and Reservoir, Willow Creek, Idaho : Hydraulic Model Investigation
Authors: Perkins, Louis Z.; Smith, Peter M.
Abstract: Ririe Dam is a 251-ft-high rockfill embankment on Willow Creek near Idaho Falls, Idaho. Flow regulation is provided by an outlet works consisting of an intake tower, two 3.75-ft by 7.0-ft slide valves, an 8.0-ft-wide by 11.25-ft-high conduit, a 20.0-ft-wide by 77.66-ft-long stilling basin, and a riprapped exit channel with bottom as wide as the stilling basin. A portion of the forebay, the hydraulic structures, and 300 ft of exit channel were reproduced in a 1:25-scale model. The model conduit was sloped to produce the computed specific energy gradient for the design discharge of 1900 cfs. The outlet works of original design was satisfactory when the stilling basin and exit channel were enlarged to provide a hydraulic jump for the maximum outlet flow of 3270 cfs. The original plan, as modified, was rejected because the valves were not readily accessible. Tests of the adopted design indicated that maximum unregulated discharges for minimum and maximum pool elevs 5023 and 5119 msl were 1847 and 4250 cfs, respectively. Flow conditions and pressures in the intake and at the valves were satisfactory. Standing waves generated in the curved upstream end of the conduit disappeared before they reached the downstream end. The stilling basin produced a good hydraulic jump for the design discharge of 1900 cfs and an acceptable jump for 4250 cfs. With 1900 cfs and maximum tailwater, the walls of the stilling basin were overtopped about 7 ft. No adverse effects resulted when the left side of the exit channel was steepened to reduce rock excavation and riprap along that side was eliminated. The 75- to 1200-lb rock proposed for riprap was more than adequate for a flow of 1900 cfs and inadequate for 4250 cfs when tested with the revised downstream exit channel. Erosion with two types of stilling basin end walls (curved to banks and 20-ft extensions of side walls) was approximately equal.
Description: Technical Report1972-01-01T00:00:00ZMcNary Reservoir Navigation at Ice Harbor Dam, Snake River, Washington : Hydraulic Model Report
https://hdl.handle.net/11681/47534
Title: McNary Reservoir Navigation at Ice Harbor Dam, Snake River, Washington : Hydraulic Model Report
Authors: United States. Army. Corps of Engineers. North Pacific Division. Hydraulic Laboratory
Abstract: A 1:100-scale model simulating the Ice Harbor Dam project and navigation channel and river downstream from the project was used to test various structural modifications in an attempt to remedy navigation problems which exist as a result of crossflow from the powerhouse. A radio-controlled scale model of a 2000-horsepower towboat with barges was used in evaluating the navigation improvements. Modifications tested included various length and geometric guide wall extensions as well as channel widening. Towboat operators assisted in evaluation of the modifications tested. None of the tested modifications succeeded (to the satisfaction of the tow operators) in correcting the difficulties experienced while navigating downstream from the Ice Harbor lock.
Description: Technical Report1983-08-01T00:00:00ZLittle Goose Dam, Snake River, Washington : Hydraulic Model Investigation
https://hdl.handle.net/11681/47529
Title: Little Goose Dam, Snake River, Washington : Hydraulic Model Investigation
Authors: Johnson, Richard L.; Perkins, Louis Z.
Abstract: A 1:100-scale hydraulic model was used to study the alignment of structures, excavation requirements, and flow conditions at Little Goose Dam. Tests of first-step construction led to relocation of the temporary fishway, use of rockfill groins along the north shore, selection of limits for disposal fills, and reductions of excavation, number of cofferdam cells, and height of embankments. The tests indicated that flow conditions during the first phase of second-step construction would be acceptable and that excavation planned for the second phase could be reduced. Approach flow into the completed spillway and powerhouse was satisfactory. The excavated tailrace could be raised 20 ft without decreasing head on the powerhouse. Poor entrance conditions into the lower lock approach were eliminated by shortening and reshaping a protective fill along the river side of the approach. Performance of the fish collection system improved when the north fishway entrance was moved upstream and a 90-ft-long rock dike was placed adjacent to the right wall of the spillway roller bucket. Differences between final design (model) and contract (prototype) structures and excavation plans had no significant effect on flow conditions in the tailrace. Should the dentates in the spillway bucket erode, the hydraulic jump will move downstream, desired head between the fishway entrances will be eliminated, and erosion of the riverbed will be increased.
Description: Technical Report1975-04-01T00:00:00ZJohn Day Dam, Columbia River, Oregon and Washington : Hydraulic Model Investigations
https://hdl.handle.net/11681/47528
Title: John Day Dam, Columbia River, Oregon and Washington : Hydraulic Model Investigations
Authors: Johnson, Richard L.; Perkins, Louis Z.
Abstract: The John Day Project includes a 20-bay spillway, a 20-unit powerhouse (ultimate installation), a single-lift navigation lock 86 ft wide by 675 ft long with a maximum lift of 113 ft, and a 24-ft-wide fish ladder on each bank of the river. Average head on the structures is about 105 ft. Excavation requirements, diversion plans, structure locations, and methods of project operation were studied in a 1:80-scale model that reproduced 2.9 miles of river channel and pertinent overbank topography. A 1:25-scale model was used to determine maximum limits for completion of skeleton powerhouse units through which the river would be diverted during third-stage construction. Improved designs were developed for the first- and second-step cofferdams, navigation lock approaches, temporary and permanent fishway entrances, auxiliary water intake for the Oregon shore fishway, powerhouse tailrace, skeleton units, and disposal fills. Limits for an interim cofferdam on the Oregon shore were evaluated; and satisfactory methods for operation of the completed spillway and fishway entrances were determined.
Description: Technical Report1972-06-01T00:00:00Z