The dam was built in 1925 as a water supply dam. [kiddle]
The dam is 1510' (460m) long with a spillway width of 802' (244m). The max discharge rate is 261kcfs. [NewarkAdvocate]
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| DelawareOhioHistory The dam cost $1.54m and holds 6.3 billion gallons of water. "The project was of such a scope that a contractor was hired that had experience building metropolitan skyscrapers; the Thompson-Starrett Company was responsible for such structures as the General Motors Building in Detroit and the landmark Woolworth Building in New York City." |
It is a fixed-crest dam (no gates on top). The current bridge doesn't appear to have any girders, just slabs.
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| Dave Neel-Surrena, Mar 2018 |
The dam is 1510' (460m) long with a spillway width of 802' (244m). The max discharge rate is 261kcfs. [NewarkAdvocate]
261kcfs is a lot. I wonder how much the downstream river valley can handle without flooding. As the river flows to Columbus, there are some rather narrow spots in the river.
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| ColumbusLibrary, 1957 photo by Matthew Mosbacher Sr., no copyright "Water spilling from the O'Shaughnessy Dam during the 1957 flood. The dam was completed June 1, 1925. The reservoir, created by damming the Scioto River, provided a needed water source for the city. The reservoir is 912 acres in size and has 18.4 miles of shoreline. Maximum depth is over 40 feet near the dam, although much of the water is 20 feet or less." |
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| DelawareOhioHistory, © JEFF HINCKLEY A 5mw power plant was installed in 1987. It was abandoned in Feb 2017. $15.3m was approved in 2023 to refurbish the plant to produce electricity again. |
The power plant can't be used all of the time because sometimes the flow in the river is too low. Since the main function of the dam is water supply, I expect they can run the plant only when water is going over the spillway. But of all the photos and videos I looked at, this was the only one that had a dry spillway. But photos are probably biased towards spilling water because they are more impressive. In general people will go out of their way to capture a big flow over the dam.
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| VisualOhio This source puts the capacity of the spillway at 100kcfs. Although the author is careful to note that the information was provided by Google Bard AI. [I presume that the Ferris wheel in the background is part of the Columbus Zoo and Aquarium. But I could not find that wheel using street view.] |
The river downstream does appear to have good capacity because the rainstorm on Aug 21 flooded I-70 a little east of here.
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| usgs |
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| W E Ayres postcard #123890 via Columbus Metro Library via Bridge Hunter |
This was the post that motivated this research.
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| Facebook Reel Victoria Vara: This dam doesn't have flood gates. It's just rolling over the normal crest. |
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