Reservoir · Oklahoma · United States · USACE CWMS
Copan Lake
33.3% full
Capacity
134.74 hm³
Volume stored
45 hm³
Coordinates
36.886°N, 95.971°W
Last updated
2026-07-30
Current fill
33.3%vs 7 days ago
-0.2%losing
vs 1 year ago
-0.1%year-over-year
7-day trend
→stable
Data source: USACE CWMS — US Army Corps of Engineers — daily reservoir storage volume. Design capacity is unavailable for this site, so fill % is estimated against the 5-year maximum storage and may overstate fullness. Last reading: 2026-07-30.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 36.886, -95.971 · Open in Google Maps
About Copan Lake
As of July 30, 2026, Copan Lake is filled to 33.3% of its total capacity, holding roughly 45 hm³ of water out of a maximum 135 hm³. At this level the reservoir is low.
Over the most recent week on record the fill level has held broadly steady (-0.2 pts), and it sits close to where it was a year earlier.
Across the readings we hold for Copan Lake — 53 data points between June 6, 2026 and July 30, 2026 — the level has ranged from a low of 33.3% (July 30, 2026) to a high of 100.0% (June 29, 2026).
It is operated by USACE primarily for multiple purposes. It lies within the Oklahoma basin at 36.886°N, 95.971°W.
Key facts
- Current fill level
- 33.3%
- Water stored
- 45 hm³
- Total capacity
- 135 hm³
- 7-day change
- ▼ 0.2 pts
- Year-on-year
- ▼ 0.1 pts
- Primary use
- Multipurpose
- River basin
- Oklahoma
- Operator
- USACE
- Coordinates
- 36.886°N, 95.971°W
- Last updated
- July 30, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 30 Jul 2026 | 33.3% | 45 |
| 29 Jul 2026 | 33.5% | 45 |
| 28 Jul 2026 | 33.5% | 45 |
| 27 Jul 2026 | 33.6% | 45 |
| 26 Jul 2026 | 33.7% | 45 |
| 25 Jul 2026 | 33.8% | 46 |
| 24 Jul 2026 | 33.8% | 46 |
| 23 Jul 2026 | 34.0% | 46 |
| 22 Jul 2026 | 34.2% | 46 |
| 21 Jul 2026 | 34.4% | 46 |
| 20 Jul 2026 | 34.3% | 46 |
| 19 Jul 2026 | 34.9% | 47 |
Frequently asked questions
What is the current water level of Copan Lake?
As of July 30, 2026, Copan Lake is at 33.3% of its capacity, holding approximately 45 hm³ of water, according to USACE CWMS (US Army Corps of Engineers) data.
Is Copan Lake reservoir full?
No. As of July 30, 2026, Copan Lake is low at 33.3% of its capacity, so it is not full.
Is the water level at Copan Lake rising or falling?
The level at Copan Lake has been broadly stable over the latest week on record (-0.2 points).
How much water can Copan Lake hold?
Copan Lake has a total capacity of 135 hm³.
Where is Copan Lake reservoir located?
Copan Lake is located in Oklahoma, United States, within the Oklahoma basin (coordinates 36.886°N, 95.971°W).
What is Copan Lake used for?
Copan Lake is used primarily for multiple purposes, and is managed by USACE.