TWCA 2016 Mid-Year Conference

1. Texas Water Conservation Association
Midyear Conference
John Hofmann
LCRA Executive Vice President of Water
June 17, 2016

2. What a difference a year makes
June 2016March 2015

3. The Highland Lakes

4. A shared resource
The Highland Lakes provide water for:
• More than a million people
• Seven power plants capable of providing power
to more than 3 million homes
• Businesses and jobs
• Agriculture
• The environment

5. Highland Lakes watershed
Lake Buchanan
Lake Travis

6. Water flowing into the
Highland Lakes
0
25,000
50,000
75,000
100,000
125,000
150,000
175,000
200,000
225,000
250,000
275,000
300,000
325,000
350,000
375,000
400,000
425,000
January February March April May June July August September October NovemberDecember
Acre-­feet
Average since 1942
Average of 2011-­2015
2011
2015
2016

7. Record-­low inflows into the
Highland Lakes
10 Lowest Annual Inflows on Record
2011 127,802 acre-­feet
2014* 209,023 acre-­feet
2013 215,138 acre-­feet
2008 284,462 acre-­feet
2006 285,229 acre-­feet
1963 392,589 acre-­feet
2012 393,163 acre-­feet
1983 433,312 acre-­feet
1999 448,162 acre-­feet
2009 499,732 acre-­feet
*Preliminary data

8. Floods
Date Comment
1938 22 floodgates opened at Buchanan Dam
Led to larger design for Mansfield Dam
1952 Filled Lake Travis overnight
Flood of Record for LBJ and Marble Falls
1957 Ended the Drought of Record
First time gates were opened at Mansfield
1991 Flood of Record for Lake Buchanan
Flood of Record for Lake Travis
1997 Llano River basin flood
2004 Upper and lower basin flood
2007 Marble Falls “Rain Bomb”

9. 1952 flood
Daily Elevations of Lake Travis
600
610
620
630
640
650
660
670
680
690
700
710
720
8/28/1952 9/27/1952 10/27/1952 11/26/1952 12/26/1952
Date
Elevation (msl)
Observed daily Lake Level
681 msl Travis is considered full
619
675

10. Rising lake levels
• In 2015:
– Lake Travis rose more than 53 feet
– Lake Buchanan rose more than 25 feet
– Combined storage increased more than 1 million
acre-­feet
• Current levels compared to Jan. 1, 2016:
– Lake Travis is about 7 feet higher
– Lake Buchanan is about 6 feet higher
– Combined storage is up about 260,000 acre-­feet

11. Full vs. full-­full
11

12. Two-­week rainfall
White boxes show totals
of about 8-­15 inches
White boxes
show totals of
about 8-­14+
inches
Some areas
received totals
of 3-­5 and even
7+ inches

13. Lake Travis elevation
Crested: 692.7 feet msl
(for water supply purposes)
Feet msl = feet above mean sea

14. Hydromet system
• Provides information vital for
flood management
• Includes more than 275 gauges
• Transmits data every 15 minutes
• Uses LCRA’s radio system
• Data is shared with partners and
the public

15. River Operations Control Center

16. Lake Travis 1991

17. Buchanan Dam
June 2

18. Our work continues …

19. Lake Travis won’t stay full
19

20. 0.0
0.5
1.0
1.5
2.0
2.5
3.0
1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015
Millions of acre-­feet
Sept. 30, 1940, to June 15, 2016
Total combined storage in
lakes Buchanan and Travis
Full storage (2.01 million acre-­feet)
Average storage (1.62 million acre-­feet)
Combined storage (million acre-­feet)

21. Questions?