Lake L. B. Johnson: 98.8% full as of 2026-09-07

Historical Data

Date Percent Full Mean Water Level
(ft)
Reservoir Storage
(acre-ft)
Conservation Storage
(acre-ft)
Conservation Capacity
(acre-ft)
Surface Area
(acres)
Today 2026-09-07 98.8 824.79 130,269 111,429 112,778 6,412
Yesterday 2026-09-06 98.8 824.79 130,269 111,429 112,778 6,412
2 days ago 2026-09-05 98.7 824.78 130,205 111,365 112,778 6,411
1 week ago 2026-08-31 98.5 824.73 129,885 111,045 112,778 6,406
1 month ago 2026-08-07 98.6 824.76 130,077 111,237 112,778 6,409
3 months ago 2026-06-07 99.0 824.82 130,462 111,622 112,778 6,415
6 months ago 2026-03-07 97.8 824.61 129,117 110,277 112,778 6,395
1 year ago 2025-09-07 98.6 824.76 130,077 111,237 112,778 6,409
*

Percent Full is based on Conservation Storage and Conservation Capacity and doesn't account for storage in flood pool.

**

   Values above, including today's are averaged conditions. For near real-time instantaneous water level, see table below or the interactive map viewer.

Most Recent Instantaneous Water Level

Date/time Water Level
(ft)
Conservation Pool Elevation
(ft)
Height Above Conservation Pool
(ft)
Most recent 2026-09-07 04:30 824.79 825.00 -0.21
1 hour prior 2026-09-07 03:30 824.78 825.00 -0.22
2 hours prior 2026-09-07 02:30 824.83 825.00 -0.17
6 hours prior 2026-09-06 22:30 824.74 825.00 -0.26
12 hours prior 2026-09-06 16:30 824.83 825.00 -0.17
24 hours prior 2026-09-06 04:30 824.77 825.00 -0.23
48 hours prior 2026-09-05 04:30 824.75 825.00 -0.25
*

Data is provisional and subject to revision.

Additional Information

Impoundment date 1951-01-01
Vertical datum NAVD88 +0.68
Dead pool elevation 793.40 ft above NAVD88 +0.68
Service spillway crest elevation 795.00 ft above NAVD88 +0.68
Emergency spillway crest elevation 835.50 ft above NAVD88 +0.68
Top of dam elevation 838.50 ft above NAVD88 +0.68
Conservation pool elevation 825.00 ft above NAVD88 +0.68
Data download (CSV) period of record, last one year, last 30 days

Elevation-Area-Capacity Curves

2007-05-01 (source: TWDB) : GIS Data
2020-06-01 (source: TWDB) : GIS Data
Data Source LCRA:2958

Lake Location