Highland Lakes and Dams

LCRA operates six dams on the lower Colorado River in Central Texas: BuchananInksWirtzStarcke, Mansfield and Tom Miller. These dams form the six Highland Lakes: Buchanan, Inks, LBJ, Marble Falls, Travis and Austin. Two of the Highland Lakes – Buchanan and Travis – are the region’s water supply reservoirs to serve more than 1 million people as well as businesses, industries, the environment and agriculture in the lower Colorado River basin.

Each of the dams was built to help manage floods and generate hydroelectric power. The dams in the Highland Lakes chain have hydroelectric generation stations that contribute to the Central Texas energy supply. Together, the hydroelectric plants at the dams can provide more than 295 megawatts of power.

Read more about LCRA's hydroelectric generation

LCRA moves water downstream to meet water supply needs through hydroelectric turbines, creating power along the way. Power generation at LCRA’s six dams along the Highland Lakes was once the major source of LCRA’s electric generation capacity, but LCRA now releases water solely to generate electricity only when directed to do so by the Electric Reliability Council of Texas. Hydroelectric generation is a small portion of the power LCRA produces today, but it remains an important part of the Texas power grid.

LCRA is in the midst of a multi-year rehabilitation program to increase the useful life, generating capacity and production efficiency of the dams.

Buchanan Dam and Lake Buchanan

Year completed: 1938
Primary purpose: Water supply, hydroelectric power
Location: Burnet and Llano counties
Owner: LCRA

Buchanan Dam and Lake Buchanan were the first completed in the Highland Lakes chain. They are named for U.S. Rep. J.P. Buchanan, who helped secure federal funds to complete the project after the original builder declared bankruptcy.

Read a fact sheet about the management of Lake Buchanan and the $51.1 million upgrade project recently completed at the dam.

Read more about Buchanan Dam and Lake Buchanan

Buchanan Dam

Dimensions

145.5 feet high, 10,988 feet long

Generating capacity

54.9 megawatts

Top of dam

1,025.5 feet above mean sea level (feet msl)

Overflow spillway elevation

1,020.35 feet msl

Floodgates

37

Discharge capacity

348,000 cubic feet per second (cfs):

  • 7 large floodgates at 18,800 cfs each
  • 30 small floodgates at 7,030 cfs each
  • 2 turbines at 2,090 cfs each
  • 1 turbine at 1,760 cfs

Original name

Hamilton Dam

Lake Buchanan

Lake area

22,452 acres

Water supply storage capacity

286.9 billion gallons

Elevation when full

1,020 feet msl

Volume when full

880,356 acre-feet

Historic high

1,021.4 feet msl on Dec. 20, 1991

Historic low

983.7 feet msl on Sept. 9, 1952

Target operating range

May through October: at or below 1,018 feet msl
November through April: at or below 1,020 feet msl

100-year flood level at dam

1,021 feet msl

Dimensions

30.65 miles long, 4.92 miles at widest point

Lowest Lake Buchanan Elevations

Rank​​ Drought Date Height* (feet msl)
1 1947-57 Sept. 9, 1952 983.70
2 2008-16 Sept. 20, 2013 985.27
3 1963-64 Sept. 20, 1964 986.63
4 1983-84 Oct. 7, 1984 987.97
5 1999-2000 Oct. 15, 2000 994.73
6 2005-06 Jan. 1, 2007 997.97
*Based on daily readings at 8 a.m.

Inks Dam and Inks Lake

Year completed: 1938
Primary purpose: Hydroelectric power
Location: Llano and Burnet counties

Inks Dam has no floodgates, and the power plant is the smallest in the Highland Lakes chain. Inks Dam works in tandem with Buchanan Dam. A small amount of water can be released through hydroelectric generation, but the bulk of floodwaters pass over an uncontrolled spillway.

The lake and dam are named for Roy B. Inks, one of the original members on the LCRA Board of Directors.

Read more about Inks Dam and Inks Lake

Inks Dam

Dimensions

96.5 feet high, 1,547.5 feet long

Generating capacity

13.8 megawatts

Top of dam

922 feet msl

Floodgates

None

Overflow spillway elevation

888.32 feet msl

Discharge capacity

3,380 cubic feet per second (cfs):

  • 1 turbine at 3,380 cfs

Original name

Arnold Dam

Inks Lake

Lake area

798 acres

Elevation when full

887.7 feet msl

Volume when full

13,772 acre-feet

Historic high

902.8 feet msl on July 25, 1938

Historic low

877.1 feet msl on Dec. 6, 1983

Target operating range

886.9 to 887.7 feet msl

100-year flood level at dam

901.7 feet msl

Dimensions

4.2 miles long, 3,000 feet at widest point

Wirtz Dam and Lake LBJ

Year completed: 1951
Primary purpose: Hydroelectric power, cooling reservoir for Thomas C. Ferguson Power Plant
Location: Burnet and Llano counties

Wirtz Dam was built in tandem with Starcke Dam downstream. The dam was named in 1952 for Alvin J. Wirtz who was instrumental in LCRA’s creation and served as its first general counsel. The lake was named in 1965 for another advocate of LCRA, President Lyndon B. Johnson.

As part of a $76 million project, LCRA is replacing Wirtz Dam’s 10 floodgates and hoist bridge sections. Read more.

Read more about Wirtz Dam and Lake LBJ

Wirtz Dam

Dimensions

118.3 feet high, 5,491.4 feet long

Generating capacity

60 megawatts

Top of dam

838.5 feet msl

Overflow spillway elevation

835.5 feet msl

Floodgates

10

Discharge capacity

319,000 cubic feet per second (cfs):

  • 10 floodgates at 30,800 cfs each
  • 2 turbines at 5,250 cfs each

Original name

Granite Shoals Dam

Lake LBJ

Lake area

6,432 acres

Elevation when full

825 feet msl

Volume when full

131,618 acre-feet

Historic high

836.2 feet msl on Sept. 11, 1952

Historic low

793.8 feet msl on Nov. 16, 1970

Target operating range

824.4 to 825 feet msl

Dimensions

21.15 miles long and 10,800 feet at widest point

100-year flood level at dam

828.1 feet msl

Original name

Lake Granite Shoals

Starcke Dam and Lake Marble Falls

Year completed: 1951
Primary purpose: Hydroelectric power
Location: Burnet County

Starcke Dam is the smallest in the Highland Lakes chain, and the last one completed. The dam was renamed in 1962 for Max Starcke, LCRA’s second general manager, who served from 1940 to 1955.

Read more about Starcke Dam and Lake Marble Falls

Starcke Dam

Dimensions

98.8 feet high, 859.5 feet long

Generating capacity

41.4 megawatts

Top of dam

761.5 feet msl

Floodgates

10

Discharge capacity

101,000 cubic feet per second (cfs):

  • 10 floodgates at 9,020 cfs each
  • 1 turbine at 5,500 cfs
  • 1 turbine at 5,200 cfs

Original name

Marble Falls Dam

Lake Marble Falls

Lake area

613 acres

Elevation when full

737 feet msl

Volume when full

7,597 acre-feet

Historic high

756.3 feet msl on Sept. 11, 1952

Historic low

715 feet msl on Oct. 4, 1983

Target operating range

736.2 to 737 feet msl

100-year flood level at dam

754.3 feet msl

Dimensions

5.75 miles long and 1,080 feet at widest point

Mansfield Dam and Lake Travis

Year completed: 1942
Primary purpose: Flood management, water supply storage, hydroelectric power
Location: Travis and Burnet counties

LCRA and the U.S. Bureau of Reclamation built Mansfield Dam from 1937 to 1942. The dam was built across a deep canyon at Marshall Ford, a long-time river crossing and settlement. After a severe flood in July 1938, LCRA raised the height of the dam to add storage capacity for floodwaters.

Lake Travis is the only lake in the Highland Lakes chain specifically designed to hold back floodwaters. Lake Travis is considered full for water supply purposes at 681 feet msl. At that level, the lake contains 1.1 million acre-feet of water. Lake Travis is designed to hold an additional 776,062 acre-feet of floodwaters in what is referred to as the flood pool.

LCRA is engaged in a multi-year, multi-million dollar renovation project to rehab and restore the dam’s floodgates to their original condition. Read the floodgate renovation project fact sheet.

Read more about Mansfield Dam and Lake Travis

Mansfield Dam

Dimensions

278 feet high, 7,089 feet long

Generating capacity

108 megawatts

Overflow spillway elevation

714 feet msl

Top of dam

750 feet msl

Floodgates

24

Discharge capacity*

*When at 681 feet msl. Discharge capacities increase as the lake level rises.

More than 131,000 cubic feet per second (cfs):

  • 23 floodgates at more than 5,250 cfs each
  • 1 variable discharge gate at 2,290 cfs
  • 2 turbines at 2,530 cfs each
  • 1 turbine at 2,520 cfs

Original name

Marshall Ford Dam

Lake Travis

Lake area

19,044 acres

Water supply storage capacity

363.3 billion gallons

Elevation when full

681 feet msl

Volume when full

1,115,076 acre-feet

Historic high

710.44 feet msl on Dec. 25, 1991

Historic low

614.18 feet msl on Aug. 14, 1951

100-year flood level at dam

722 feet msl

Top 10 highest levels for Lake Travis

​Rank ​Date ​Height* (feet msl)
1 ​Dec. 25, 1991
​710.44
​2 ​May 18, 1957
​707.38
​3 ​June 26, 1997
​705.11
​4 ​Feb. 8, 1992
​704.83
​5 ​Oct. 20, 2018 ​704.39
​6 ​July 6, 2007 ​701.52
​7 ​Nov. 24, 2004
​696.70
​8 ​June 14, 1987
​693.48
9 ​July 7, 2002
​693.47
​10 June 7, 2016 ​692.70

Lowest Lake Travis Elevations

​R​​​ank Drought ​Date ​Height* (feet msl)
​1 1947-57 ​Aug. 14, 1951 ​614.18
​2 1963-64 ​Nov. 8, 1963 ​615.02
3 2008-16 ​Sept. 20, 2013 ​618.56
​4 1983-84 ​Oct. 7, 1984 ​636.58
​5 1999-2000 ​Oct. 15, 2000 ​640.24
​6 2005-06 ​Dec. 13, 2006 ​643.55

*Based on daily readings at 8 a.m.

Tom Miller Dam and Lake Austin

Year completed: 1940
Primary purpose: Hydroelectric power, water supply
Location: Travis County

LCRA built Tom Miller Dam on property leased from the City of Austin. Named for an Austin mayor, the dam was built atop the remains of two earlier structures, both called Austin Dam. The first was built from 1890 to 1893, and the other from 1912 to 1915. Massive floods destroyed the first dam and heavily damaged the second.

In October 2020, LCRA completed a major project to replace the original floodgates on Tom Miller Dam to help maintain continued reliability and safety of the dam for generations to come. The $10.8 million project continues LCRA’s investment in the dam and marks the dam’s second extensive renovation since it was completed in 1940.

Read more Tom Miller Dam and Lake Austin

Tom Miller Dam

Dimensions

100.5 feet high, 1,590 feet long

Generating capacity

17 megawatts

Top of dam

517 feet msl

Overflow spillway elevation

492.8 feet msl

Floodgates

9

Discharge capacity

108,000 cubic feet per second (cfs):

  • 4 large floodgates at 15,300 cfs each
  • 5 small floodgates at 8,580 cfs each
  • 1 turbine at 1,970 cfs
  • 1 turbine at 1,750 cfs

Lake Austin

Lake area

1,830 acres

Elevation when full

492.8 feet msl

Volume when full

24,644 acre-feet

Historic high

495.2 feet msl on May 25, 1981

Historic low

474.3 feet msl on Feb. 17, 1963

Target operating range

491.8 to 492.8 feet msl

100-year flood level at dam

493 feet msl

Dimensions

20.25 miles long, 1,300 feet at widest point

Original name

Lake McDonald