Notes

2013-06-19: The vertical datums of gauge, conservation pool and dead pool elevations for this lake have been adjusted to NAVD88+0.68ft.

Lake L. B. Johnson: 98.8% full as of 2022-12-07

The elevation-storage rating curve used to produce the storage hydrograph is made of two segments: (1) the segment up to the conservation pool top (below the red line) is based on measured data, and (2) the segment in the flood pool (above the red line) is an extrapolation from the first segment and shouldn't be relied upon for flood storage information.

Historical Data

Date Percent Full Mean Water Level
(ft)
Reservoir Storage
(acre-ft)
Conservation Storage
(acre-ft)
Conservation Capacity
(acre-ft)
Surface Area
(acres)
Most recent 2022-12-07 98.8 824.79 130,269 111,429 112,778 6,412
1 day prior 2022-12-06 98.8 824.79 130,269 111,429 112,778 6,412
2 days prior 2022-12-05 98.7 824.78 130,205 111,365 112,778 6,411
1 week prior 2022-11-30 98.7 824.78 130,205 111,365 112,778 6,411
1 month prior 2022-11-07 98.6 824.76 130,077 111,237 112,778 6,409
3 months prior 2022-09-07 98.2 824.69 129,628 110,788 112,778 6,403
6 months prior 2022-06-07 98.3 824.70 129,693 110,853 112,778 6,404
1 year prior 2021-12-07 97.9 824.63 129,244 110,404 112,778 6,397
*

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 2022-12-08 03:45 824.78 825.00 -0.22
1 hour prior 2022-12-08 02:45 - n.a. - - n.a. - - n.a. -
2 hours prior 2022-12-08 01:45 - n.a. - - n.a. - - n.a. -
6 hours prior 2022-12-07 21:45 - n.a. - - n.a. - - n.a. -
12 hours prior 2022-12-07 15:45 824.78 825.00 -0.22
24 hours prior 2022-12-07 03:45 824.81 825.00 -0.19
48 hours prior 2022-12-06 03:45 824.79 825.00 -0.21
*

Data is provisional and subject to revision.

Additional Information

Impoundment date 1951-01-01
Gauge LCRA:2958
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
Top of flood gate elevation 826.00 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

Lake Location