Reservoir · Oklahoma · United States · USACE CWMS
Fort Supply Lake
75.9% full
Capacity
17.15 hm³
Volume stored
13 hm³
Coordinates
36.554°N, 99.571°W
Last updated
2026-10-01
Current fill
75.9%vs 7 days ago
+1.3%gaining
vs 1 year ago
N/A7-day trend
→stable
Data source: USACE CWMS — US Army Corps of Engineers — daily reservoir storage volume. Capacity is the design (normal full-pool) capacity from the US National Inventory of Dams (NID); fill % = current volume ÷ design capacity. Last reading: 2026-10-01.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 36.554, -99.571 · Open in Google Maps
About Fort Supply Lake
As of October 1, 2026, Fort Supply Lake is filled to 75.9% of its total capacity, holding roughly 13 hm³ of water out of a maximum 17 hm³. At this level the reservoir is within its normal operating range.
Over the most recent week on record the fill level has held broadly steady (+1.3 pts).
Across the readings we hold for Fort Supply Lake — 329 data points between October 2, 2021 and October 1, 2026 — the level has ranged from a low of 74.3% (September 23, 2026) to a high of 104.4% (January 31, 2022). On average the reservoir is fullest around January and at its lowest around September.
It is operated by USACE primarily for multiple purposes. It lies within the Oklahoma basin at 36.554°N, 99.571°W.
Key facts
- Current fill level
- 75.9%
- Water stored
- 13 hm³
- Total capacity
- 17 hm³
- 7-day change
- ▲ 1.3 pts
- Primary use
- Multipurpose
- River basin
- Oklahoma
- Operator
- USACE
- Coordinates
- 36.554°N, 99.571°W
- Last updated
- October 1, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 1 Oct 2026 | 75.9% | 13 |
| 30 Sep 2026 | 75.9% | 13 |
| 29 Sep 2026 | 75.6% | 13 |
| 28 Sep 2026 | 75.6% | 13 |
| 27 Sep 2026 | 75.6% | 13 |
| 26 Sep 2026 | 75.6% | 13 |
| 25 Sep 2026 | 75.1% | 13 |
| 24 Sep 2026 | 74.6% | 13 |
| 23 Sep 2026 | 74.3% | 13 |
| 22 Sep 2026 | 74.6% | 13 |
| 21 Sep 2026 | 74.6% | 13 |
| 20 Sep 2026 | 74.7% | 13 |