Spillway for Little Goose Dam, Snake River, Washington, Hydraulic Model Investigation
Spillway for Little Goose Dam, Snake River, Washington, Hydraulic Model Investigation

Author:

Publisher:

Published: 1975

Total Pages: 0

ISBN-13:

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The spillway for Little Goose Dam, designed to pass discharges up to 850,000 cfs (2125 cfs per ft of crest), was studied in a 1:42.47-scale, 3-bay, sectional model and a 1:100-scale general model to investigate the performance of various elements of the structure and to determine flow conditions in the tailrace. Maximum velocities that fluctuated between 5 and 12 fps along the north embankment upstream from the spillway were indicated by the spillway model. Tests indicated that the stilling basin of original design was not satisfactory. An acceptable stilling basin was developed in the model, but unusual artesian flow at the site would have required a costly drainage system to protect the basin slab against uplift. Sixteen roller bucket plans were investigated in efforts to eliminate the basin slab and drainage system. A modified Angostura-type bucket, with simpler teeth and shorter apron, was adopted.

Spillway for Little Goose Dam, Snake River, Washington
Spillway for Little Goose Dam, Snake River, Washington

Author:

Publisher:

Published: 1975

Total Pages: 0

ISBN-13:

DOWNLOAD EBOOK

The spillway for Little Goose Dam, designed to pass discharges up to 850,000 cfs (2125 cfs per ft of crest), was studied in a 1:42.47-scale, 3-bay, sectional model and a 1:100-scale general model to investigate the performance of various elements of the structure and to determine flow conditions in the tailrace. Maximum velocities that fluctuated between 5 and 12 fps along the north embankment upstream from the spillway were indicated by the spillway model. Tests indicated that the stilling basin of original design was not satisfactory. An acceptable stilling basin was developed in the model, but unusual artesian flow at the site would have required a costly drainage system to protect the basin slab against uplift. Sixteen roller bucket plans were investigated in efforts to eliminate the basin slab and drainage system. A modified Angostura-type bucket, with simpler teeth and shorter apron, was adopted.

Spillway Tailwater Erosion at Little Goose Dam, Snake River, Washington. Hydraulic Model Investigation
Spillway Tailwater Erosion at Little Goose Dam, Snake River, Washington. Hydraulic Model Investigation

Author: M. M. Kubo

Publisher:

Published: 1983

Total Pages: 76

ISBN-13:

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Underwater inspection of the Little Goose Dam roller bucket and tailwater channel following about 10 years of operation revealed foundation erosion around various structures and the end of the bucket. A 1:50-scale movable-bed model was used to evaluate the effect of high spillway discharges on the erosional tendencies in the tailwater channel. Studies were accomplished to establish the most desirable spillway operating schedule which would flush the riverbed material and debris from the roller bucket.