Lake L. B. Johnson: 98.7% full as of 2026-09-13
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 | 2026-09-13 | 98.7 | 824.77 | 130,141 | 111,301 | 112,778 | 6,410 |
| Yesterday | 2026-09-12 | 98.9 | 824.81 | 130,397 | 111,557 | 112,778 | 6,414 |
| 2 days ago | 2026-09-11 | 98.9 | 824.81 | 130,397 | 111,557 | 112,778 | 6,414 |
| 1 week ago | 2026-09-06 | 98.8 | 824.79 | 130,269 | 111,429 | 112,778 | 6,412 |
| 1 month ago | 2026-08-13 | 98.4 | 824.72 | 129,821 | 110,981 | 112,778 | 6,406 |
| 3 months ago | 2026-06-13 | 98.7 | 824.77 | 130,141 | 111,301 | 112,778 | 6,410 |
| 6 months ago | 2026-03-13 | 98.6 | 824.75 | 130,013 | 111,173 | 112,778 | 6,408 |
| 1 year ago | 2025-09-13 | 98.7 | 824.77 | 130,141 | 111,301 | 112,778 | 6,410 |
*
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 | 2026-09-13 19:00 | 824.72 | 825.00 | -0.28 |
| 1 hour prior | 2026-09-13 18:00 | 824.77 | 825.00 | -0.23 |
| 2 hours prior | 2026-09-13 17:00 | 824.79 | 825.00 | -0.21 |
| 6 hours prior | 2026-09-13 13:00 | 824.75 | 825.00 | -0.25 |
| 12 hours prior | 2026-09-13 07:00 | 824.75 | 825.00 | -0.25 |
| 24 hours prior | 2026-09-12 19:00 | 824.79 | 825.00 | -0.21 |
| 48 hours prior | 2026-09-11 19:00 | 824.79 | 825.00 | -0.21 |
*
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
