Lake J.B. Thomas is 67.4% full as of 2016-06-30

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, while 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.

Date Percent Full Mean Water Level
(ft)
Reservoir Storage
(acre-ft)
Conservation Storage
(acre-ft)
Conservation Capacity
(acre-ft)
Surface Area
(acres)
Today 2016-06-30 67.4 2,247.69 135,479 134,806 199,931 5,782
Yesterday 2016-06-29 67.5 2,247.72 135,653 134,980 199,931 5,785
2 days ago 2016-06-28 67.6 2,247.74 135,769 135,096 199,931 5,788
1 week ago 2016-06-23 68.0 2,247.89 136,637 135,964 199,931 5,804
1 month ago 2016-05-30 68.4 2,248.01 137,335 136,662 199,931 5,817
3 months ago 2016-03-30 69.9 2,248.54 140,434 139,761 199,931 5,875
6 months ago 2015-12-30 72.6 2,249.45 145,825 145,152 199,931 5,974
1 year ago 2015-06-30 76.0 2,250.59 152,705 152,032 199,931 6,095
*

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 2016-06-30 17:45 2,247.68 2,258.0 -10.3 below flood pool
1 hour prior 2016-06-30 16:45 2,247.68 2,258.0 -10.3 below flood pool
2 hours prior 2016-06-30 15:45 2,247.69 2,258.0 -10.3 below flood pool
6 hours prior 2016-06-30 11:45 2,247.69 2,258.0 -10.3 below flood pool
12 hours prior 2016-06-30 05:45 2,247.69 2,258.0 -10.3 below flood pool
24 hours prior 2016-06-29 17:45 2,247.72 2,258.0 -10.3 below flood pool
48 hours prior 2016-06-28 17:45 2,247.73 2,258.0 -10.3 below flood pool
*

Data is provisional and subject to revision.

Additional Information

Impoundment date 1952-01-01
Vertical datum NGVD29
Gauge USGS:08118000
Dead pool elevation 2200.0 ft above NGVD29
Service spillway crest elevation 2258 ft above NGVD29
Conservation pool elevation 2258.0 ft above NGVD29
Emergency spillway crest elevation 2264.0 ft above NGVD29
Emergency spillway crest elevation 2267.0 ft above NGVD29
Maximum design elevation 2275 ft above NGVD29
Top of dam elevation 2280 ft above NGVD29
Data download (CSV) period of record, last one year, last 30 days

Elevation-Area-Capacity Curves

1952-01-01 (source: usgs)
1999-11-01 (source: twdb) : GIS Data