LakeLevelIs Keyhole Reservoir low right now?
Keyhole Reservoir was at 4,083.83 ft on October 10, 2026, 15.47 ft below its full pool of 4,099.3 ft. That is 8.30 ft below the typical level for October 10 — lower than in 9 of 10 past years. Over the past week the lake has been steady.
Keyhole Reservoir on Oct 10 in past years
Daily levels, last two weeks
| Date | Level (ft) | Change | vs full pool |
|---|---|---|---|
| Oct 10 | 4,083.83 | −0.01 | −15.5 |
| Oct 9 | 4,083.84 | −0.02 | −15.5 |
| Oct 8 | 4,083.86 | ±0.00 | −15.4 |
| Oct 7 | 4,083.86 | −0.02 | −15.4 |
| Oct 6 | 4,083.88 | ±0.00 | −15.4 |
| Oct 5 | 4,083.88 | −0.01 | −15.4 |
| Oct 4 | 4,083.89 | −0.01 | −15.4 |
| Oct 3 | 4,083.90 | −0.01 | −15.4 |
| Oct 2 | 4,083.91 | −0.01 | −15.4 |
| Oct 1 | 4,083.92 | −0.01 | −15.4 |
| Sep 30 | 4,083.93 | −0.01 | −15.4 |
| Sep 29 | 4,083.94 | −0.01 | −15.4 |
| Sep 28 | 4,083.95 | −0.01 | −15.4 |
| Sep 27 | 4,083.96 | −0.01 | −15.3 |
About Keyhole Reservoir
- Full pool
- 4,099.3 ft (Top of Conservation)
- 10-year range
- 4,083.8 ft (October 10, 2026) to 4,102.0 ft (March 29, 2019)
- Operated by
- U.S. Army Corps of Engineers
- Data
- U.S. Army Corps of Engineers — NWDM district, KEYO
- Datum
- LOCAL
Lakes near Keyhole Reservoir
- Deerfield ReservoirSouth Dakota · 55 mi 5,903.1 ft −0.8 wkLower than usual for this time of year
- Belle Fourche ReservoirSouth Dakota · 60 mi 2,956.8 ft +0.3 wkLower than usual for this time of year
- Pactola ReservoirSouth Dakota · 67 mi 4,558.2 ft +0.3 wkLower than usual for this time of year
- Cottonwood Springs ReservoirSouth Dakota · 89 mi 3,848.4 ft −0.1 wkLower than usual for this time of year
- Cold Brook ReservoirSouth Dakota · 91 mi 3,585.1 ft −0.0 wkAt full pool
- Angostura ReservoirSouth Dakota · 97 mi 3,169.3 ft −103.3 wkLower than usual for this time of year
Questions
Is Keyhole Reservoir low right now?
Keyhole Reservoir was at 4,083.83 ft on October 10, 2026, 15.47 ft below its full pool of 4,099.3 ft. That is 8.30 ft below the typical level for October 10 — lower than in 9 of 10 past years. Over the past week the lake has been steady.
What is full pool for Keyhole Reservoir?
Full pool (Top of Conservation) is 4,099.3 ft above sea level, per U.S. Army Corps of Engineers. Levels above it mean the operator is storing flood water; levels below it are normal in late summer and winter drawdowns.
How often is the Keyhole Reservoir level updated?
The operator reports every 15 minutes to an hour. This page refreshes several times a day; the time of the latest reading is shown next to the level.
Where does this data come from?
U.S. Army Corps of Engineers (NWDM district, KEYO). Readings are provisional and can be revised.