Reservoir · Oklahoma · United States · USACE CWMS
Foss Lake
94.1% full
Capacity
208.13 hm³
Volume stored
196 hm³
Coordinates
35.538°N, 99.178°W
Last updated
2026-06-11
Current fill
94.1%vs 7 days ago
-0.1%losing
vs 1 year ago
-2.1%year-over-year
7-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: 2026-06-11.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 35.538, -99.178 · Open in Google Maps
About Foss Lake
As of June 11, 2026, Foss Lake is filled to 94.1% of its total capacity, holding roughly 196 hm³ of water out of a maximum 208 hm³. At this level the reservoir is high.
Over the most recent week on record the fill level has held broadly steady (-0.1 pts), and it is 2.1 points below its level on the same date a year earlier.
Across the readings we hold for Foss Lake — 329 data points between June 13, 2021 and June 11, 2026 — the level has ranged from a low of 87.2% (January 6, 2022) to a high of 97.1% (February 16, 2026). On average the reservoir is fullest around February and at its lowest around January.
It is operated by USACE primarily for multiple purposes. It lies within the Oklahoma basin at 35.538°N, 99.178°W.
Key facts
- Current fill level
- 94.1%
- Water stored
- 196 hm³
- Total capacity
- 208 hm³
- 7-day change
- ▼ 0.1 pts
- Year-on-year
- ▼ 2.1 pts
- Primary use
- Multipurpose
- River basin
- Oklahoma
- Operator
- USACE
- Coordinates
- 35.538°N, 99.178°W
- Last updated
- June 11, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 11 Jun 2026 | 94.1% | 196 |
| 10 Jun 2026 | 94.2% | 196 |
| 9 Jun 2026 | 94.3% | 196 |
| 8 Jun 2026 | 94.5% | 197 |
| 7 Jun 2026 | 94.5% | 197 |
| 6 Jun 2026 | 94.5% | 197 |
| 5 Jun 2026 | 94.4% | 196 |
| 4 Jun 2026 | 94.2% | 196 |
| 3 Jun 2026 | 94.2% | 196 |
| 2 Jun 2026 | 94.3% | 196 |
| 1 Jun 2026 | 94.4% | 197 |
| 31 May 2026 | 94.5% | 197 |
Frequently asked questions
What is the current water level of Foss Lake?
As of June 11, 2026, Foss Lake is at 94.1% of its capacity, holding approximately 196 hm³ of water, according to USACE CWMS (US Army Corps of Engineers) data.
Is Foss Lake reservoir full?
No. As of June 11, 2026, Foss Lake is high at 94.1% of its capacity, so it is not full.
Is the water level at Foss Lake rising or falling?
The level at Foss Lake has been broadly stable over the latest week on record (-0.1 points).
How much water can Foss Lake hold?
Foss Lake has a total capacity of 208 hm³.
Where is Foss Lake reservoir located?
Foss Lake is located in Oklahoma, United States, within the Oklahoma basin (coordinates 35.538°N, 99.178°W).
What is Foss Lake used for?
Foss Lake is used primarily for multiple purposes, and is managed by USACE.