Wirtz Dam, in conjunction with downstream Starcke Dam, was the final step in the Colorado River’s Highland Lakes system. Construction on Wirtz Dam, a concrete and earthfill structure, was begun in September 1948 and was completed in November 1951. Some sources place completion in 1950, however deliberate impoundment of water began in May 1951, and the dam’s dedication (with LBJ AND Max Starcke present) was June 15, 1952 (LCRA archive photo (
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Originally called Granite Shoals for the granite outcrops along the river, now drowned by the lake, the dam was renamed in 1952 for Alvin J. Wirtz (instrumental in LCRA's creation and its first general counsel) and the lake was renamed in 1965 for another advocate of LCRA: President Lyndon B. Johnson.
A ‘constant-level’ lake, Lake LBJ’s primary purpose is to provide hydroelectric power, as well as supplying cooling water for LCRA's Thomas C. Ferguson Power Plant along Horseshoe Bay. Except during floods, the only water released from the lake is through the hydroelectric turbines.
It is worth viewing the dam via Google Earth for interesting detail that you cannot see from the ground.
The listed coordinates are for the dam itself. A neck-craning side view can be had from overflow parking lot for the nearby marina at N30 33.200 W098 20.130. Unfortunately, in this post-9/11 world, only the most oblique or distant views of the dam are available – the low water crossing below it being fenced off. For the purpose of this waymark, however, other up and downstream views of the dam are encouraged – and please include where and why you visited in your log!
Just some FAQs (courtesy LCRA)
FYI: WIRTZ DAM
Location: Llano and Burnet counties, 387 river miles from the Gulf of Mexico
When built: 1949 to 1951
Dam dimensions: 118.3 feet high, 5,491.4 feet long
Primary purpose: Hydroelectric power, cooling water for Thomas C. Ferguson Power Plant
Generating capacity: 60 megawatts
Top of dam: 838 feet above msl
Floodgates: 10
Discharge capacity: 317,400 cubic feet per second (cfs):
+ 10 floodgates @ 30,800 cfs each
+ 2 turbines @ 4,700 cfs each
Original name: Granite Shoals Dam
DETAILS ON LAKE LBJ
Lake area: 6,256 acres
Lake elevation when full: 825 feet above mean sea level (msl)
Volume when full: 133,216 acre-feet
Historic high: 836.2 feet above msl on Sept. 11, 1952
Historic low: 793.8 feet above msl on Nov. 16, 1970
Target operating range: 824.4 feet to 825 feet above msl
100-year flood level at dam: 828.1 feet above msl
Dimensions: 21.15 miles long and 10,800 feet at widest point
Original name: Lake Granite Shoals
For more background, see:
Lake Lyndon B. Johnson Public Access Facilities (
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Historic photos of Wirtz Dam LCRA archives (
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LBJ Time Machine 1952 (LBJ Library) (
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Once named Granite Shoals Wirtz Dam and Lake LBJ (
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Wirtz Dam (
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LCRA's Historic Moment: History of the Highland Lakes (
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The history of LCRA Early years and first critical test (
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LCRA as discussed by Wikipedia (
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LCRA dams form the Highland Lakes
Structures designed for flood management, water supply, hydroelectricity (
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Texas State Historical Association The Handbook of Texas Online:
Lower Colorado River Authority (
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Lake Lyndon B. Johnson (
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Granite Shoals, TX (
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