Lake L. B. Johnson: 97.7% full as of 2026-10-18

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 2026-10-18 97.7 824.60 129,053 110,213 112,778 6,394
Yesterday 2026-10-17 97.8 824.62 129,181 110,341 112,778 6,396
2 days ago 2026-10-16 98.3 824.71 129,757 110,917 112,778 6,405
1 week ago 2026-10-11 98.2 824.69 129,628 110,788 112,778 6,403
1 month ago 2026-09-18 98.5 824.74 129,949 111,109 112,778 6,407
3 months ago 2026-07-18 94.3 824.00 125,234 106,394 112,778 6,330
6 months ago 2026-04-18 98.7 824.77 130,141 111,301 112,778 6,410
1 year ago 2025-10-18 97.8 824.62 129,181 110,341 112,778 6,396
*

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 2026-10-18 17:30 824.69 825.00 -0.31
1 hour prior 2026-10-18 16:30 824.68 825.00 -0.32
2 hours prior 2026-10-18 15:30 824.67 825.00 -0.33
6 hours prior 2026-10-18 11:30 824.64 825.00 -0.36
12 hours prior 2026-10-18 05:30 824.60 825.00 -0.40
24 hours prior 2026-10-17 17:30 824.66 825.00 -0.34
48 hours prior 2026-10-16 17:30 824.74 825.00 -0.26
*

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