1. Ground Water Balance at Barton Springs
Seyoum Asamenaw
Surface Water Hydrology,
03/23/2005

2. Out line Study Objectives The Study area (Geology, Hydrogeology)
Ground Water Recharge
Cell Water Budget
What is left

3. Study objectives Estimating the Ground Water Recharge
Calibrating the Modflow model and doing water budget study for the model boundary
Interpreting the predictive simulations through 2050

4. The Edwards Aquifer

5. Barton Springs : http://www.edwardsaquifer.net/
Part of the Edwards Aquifer
Includes Travis and Hay counties
80 % unconfined
20% confined
85 % of recharge comes from Streams
15 % diffused inter stream recharge :

6. Geology Lower Cretaceous Carbonate
Marine Transgressive-Regressive sediments
Conglomerate, Shale, Marl, Sand Stone, Austin Chalk and Del Rio Clay

7. Hydrogeology
Geology
Drainage Area
Recharge Zone
Artesian Zone

8. Cell Water Budget

9. Change in storage

10. Estimating Recharge

11. Estimating Recharge Year 2002 Gage at loop 360 (cfs) Lost Creek (cfs)
Barton Springs (cfs)
Est. R (cfs)
Est. R (feet/day/cell)
January
55.2
72.3
112 35
0.1223
February
17.3
34.6
109 30
0.1033
March
3.34
19.2
102 19
0.0664
April
1.39
14.9 98 15
0.0515
May
0.017
3.39
90.5 3
0.0117
June
16.9
20.6
79.7
0.0712
July
494
592
96.7
138
0.4769
August
9.3
33.8
101
0.1029
September
0.032
9.94 92 10
0.0344
October
34.1
48.3
85.8 32
0.1101
November
78.2
98.7
98.2 39
0.1361
December
115
130
106 44
0.1532

12. On going and future works
Calibrating the predictive simulation through 2050
Writing the report

13. Thanks
Dr. Maidment
Gil Strassberg