Monticello Reservoir: 77.0% full as of 2026-08-23

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 2026-08-23 77.0 335.66 26,737 26,737 34,740 1,612
Yesterday 2026-08-22 77.0 335.66 26,737 26,737 34,740 1,612
2 days ago 2026-08-21 77.1 335.68 26,769 26,769 34,740 1,614
1 week ago 2026-08-16 77.7 335.82 26,996 26,996 34,740 1,624
1 month ago 2026-07-23 80.3 336.36 27,907 27,907 34,740 1,672
3 months ago 2026-05-23 81.3 336.55 28,234 28,234 34,740 1,689
6 months ago 2026-02-23 78.7 336.02 27,330 27,330 34,740 1,641
1 year ago 2025-08-23 81.6 336.61 28,338 28,338 34,740 1,694
*

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 2026-08-23 18:15 335.65 340.00 -4.35
1 hour prior 2026-08-23 17:15 335.65 340.00 -4.35
2 hours prior 2026-08-23 16:15 335.65 340.00 -4.35
6 hours prior 2026-08-23 12:15 335.66 340.00 -4.34
12 hours prior 2026-08-23 06:15 335.68 340.00 -4.32
24 hours prior 2026-08-22 18:15 335.64 340.00 -4.36
48 hours prior 2026-08-21 18:15 335.68 340.00 -4.32
*

Data is provisional and subject to revision.

Additional Information

Impoundment date 1973-01-01
Vertical datum NGVD29
Service spillway crest elevation 328.00 ft above NGVD29
Emergency spillway crest elevation 343.50 ft above NGVD29
Top of dam elevation 352.00 ft above NGVD29
Conservation pool elevation 340.00 ft above NGVD29
Data download (CSV) period of record, last one year, last 30 days

Elevation-Area-Capacity Curves

1998-02-01 (source: TWDB) : GIS Data
Data Source USGS:07344488
USGS Monitoring Location USGS:07344488

Lake Location