Gavins Point Dam - Yankton, SD - USA
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beta59
N 42° 51.111 W 097° 28.923
14T E 624023 N 4745480
Gavins Point Dam is a hydroelectric dam on the Missouri River on the border between Nebraska and South Dakota. Built from 1952 to 1957, it retains Lewis and Clark Lake.
Waymark Code: WMFGC4
Location: South Dakota, United States
Date Posted: 10/16/2012
Views: 8
The Gavins Point Dam is located just west of Yankton, South Dakota. It is the first of the six major Missouri River dams when heading upstream, or the last of the six when heading downstream. It was authorized in 1944 as part of the Pick-Sloan Act, which sought to control the floods on the Missouri River and provide electrical power as a side benefit.
While being the smallest of the 6 major dams, the Gavins Point dam is still very impressive at 8,700 feet long and 74 feet high, with a typical waterfall of 45 feet. The spillway is 664 feet long and features 14 tainter gates, each 40 feet wide by 30 feet tall. The power plant has three generators each with a capacity of 44 megawatts, for a total maximum output of 132.32 megawatts. However, the power-plant typically runs at about 120-megawatts of power output, enough to supply the needs of 65,000 people. From this point and north to eastern Montana, the river is very much like a stairway with each dam being a tall step. Water flows down these steps, generating electricity on each step. As a result, water that flows through the powerhouse at Gavins Point dam may have generated power 6 different times so far.
The Gavins Point Dam is a major center for recreation for the upper plains area. There are fishing and boating opportunities, a visitor center that offers power house tours, and a well developed campground. History remembers news anchor Tom Brokaw who was a tour guide at the Gavins Point Dam in 1958. Downstream, the Missouri River channel is untamed most of the way down to Sioux Falls, one of the only non-channelized portions of the Mighty Mo downstream of central Montana.
The Gavins Point Dam garnered a lot of attention during the historic flood of 2011. The flood was caused by record snowfalls and then record spring rains. The large storage dams could not hold all of this water, so it was released downstream. The US Army Corps of Engineers had no choice but to let the water through Gavins Point. The flow reached an all time high volume of 150,000 cubic feet per second on June 14, 2011, six times the typical flow rate. All this water caused massive flooding downstream. The flooding lingered through the summer of 2011, and the resulting silt covered large swathes of farmland, causing the 2012 crops to be lost as well.
As the water flow returned to more normal levels, the US Army Corps of Engineers noted an anomaly with the dam structure. Water flow was completely turned off between 8 AM and 4 PM on Wednesday, May 9, 2012, to give access to the spillway apron to be check with ground penetrating radar. A small amount of concrete damage was found, some erosion of a gravel frost blanket, and a few small voids in the gravel under the spillway. This damage is not considered to be serious. The Corps plans to fix the structure during the summer of 2012.
The dam has a hydroelectric plant with three generators, each having a nameplate capacity of 44,099 kW, for a total of 132.297 MW.
Operational: yes
Type of power station: Conventional (dams)
Type of turbine: Kaplan
Operator: US Army Corps of Engineers
Visitor center: yes
Date built: 01/01/1955
Generation capacity: 44,099 kW, for a total of 132.297 MW
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Visit Instructions:
For posting a log to an existing waymark, you will need to post a unique picture of the power station. If is not open to the public, please do not enter private property. A picture from the distance is sufficent. If it's possible to enter the machine hall, a picture of it would be nice. Please add some additional informations if possible.