Lake Alan Henry: 77.6% full as of 2018-09-21

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 2018-09-21 77.6 2,211.44 73,528 73,528 94,808 2,267
1 day prior 2018-09-20 77.2 2,211.31 73,234 73,234 94,808 2,260
2 days prior 2018-09-19 77.3 2,211.34 73,301 73,301 94,808 2,262
1 week prior 2018-09-14 77.6 2,211.45 73,550 73,550 94,808 2,267
1 month prior 2018-08-21 78.6 2,211.89 74,553 74,553 94,808 2,290
3 months prior 2018-06-21 82.4 2,213.42 78,120 78,120 94,808 2,371
6 months prior 2018-03-21 82.5 2,213.48 78,262 78,262 94,808 2,374
1 year prior 2017-09-21 86.9 2,215.20 82,420 82,420 94,808 2,459
*

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 2018-09-21 23:30 2,211.97 2,220.0 -8.0 below flood pool
1 hour prior 2018-09-21 22:30 2,211.96 2,220.0 -8.0 below flood pool
2 hours prior 2018-09-21 21:30 2,211.94 2,220.0 -8.1 below flood pool
6 hours prior 2018-09-21 17:30 2,211.85 2,220.0 -8.2 below flood pool
12 hours prior 2018-09-21 11:30 2,211.40 2,220.0 -8.6 below flood pool
24 hours prior 2018-09-20 23:30 2,211.29 2,220.0 -8.7 below flood pool
48 hours prior 2018-09-19 23:30 2,211.33 2,220.0 -8.7 below flood pool
*

Data is provisional and subject to revision.

Additional Information

Impoundment date 1994-01-01
Vertical datum NGVD29
Gauge USGS:08079700
Service spillway crest elevation 2,220.0 ft above NGVD29
Emergency spillway crest elevation 2,240.0 ft above NGVD29
Maximum design elevation 2,245.0 ft above NGVD29
Top of dam elevation 2,263.0 ft above NGVD29
Conservation pool elevation 2,220.0 ft above NGVD29
Data download (CSV) period of record, last one year, last 30 days

Elevation-Area-Capacity Curves

1993-10-01 (source: usgs)
1994-01-01 (source: usgs)
2005-07-01 (source: twdb) : GIS Data

Lake Location