Reservoir · Montana · United States · BOR RISE
Lake Como and Como Dam (CMO)
83.1% full
Capacity
47.48 hm³
Volume stored
39 hm³
Coordinates
46.062°N, 114.233°W
Last updated
2026-07-28
Current fill
83.1%vs 7 days ago
-1.4%losing
vs 1 year ago
-18.5%year-over-year
7-day trend
→stable
Data source: BOR RISE — US Bureau of Reclamation — 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: 2026-07-28.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 46.062, -114.233 · Open in Google Maps
About Lake Como and Como Dam (CMO)
As of July 28, 2026, Lake Como and Como Dam (CMO) is filled to 83.1% of its total capacity, holding roughly 39 hm³ of water out of a maximum 47 hm³. At this level the reservoir is high.
Over the most recent week on record the fill level has held broadly steady (-1.4 pts), and it is 18.5 points below its level on the same date a year earlier.
Across the readings we hold for Lake Como and Como Dam (CMO) — 2188 data points between July 31, 2021 and July 28, 2026 — the level has ranged from a low of 9.2% (October 14, 2021) to a high of 102.3% (June 29, 2022). On average the reservoir is fullest around June and at its lowest around October.
It is operated by BOR primarily for multiple purposes. It lies within the Montana basin at 46.062°N, 114.233°W.
Key facts
- Current fill level
- 83.1%
- Water stored
- 39 hm³
- Total capacity
- 47 hm³
- 7-day change
- ▼ 1.4 pts
- Year-on-year
- ▼ 18.5 pts
- Primary use
- Multipurpose
- River basin
- Montana
- Operator
- BOR
- Coordinates
- 46.062°N, 114.233°W
- Last updated
- July 28, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 28 Jul 2026 | 83.1% | 39 |
| 27 Jul 2026 | 84.5% | 40 |
| 26 Jul 2026 | 85.8% | 41 |
| 25 Jul 2026 | 87.1% | 41 |
| 24 Jul 2026 | 88.3% | 42 |
| 23 Jul 2026 | 89.5% | 42 |
| 22 Jul 2026 | 90.6% | 43 |
| 21 Jul 2026 | 91.6% | 44 |
| 20 Jul 2026 | 92.8% | 44 |
| 19 Jul 2026 | 93.8% | 45 |
| 18 Jul 2026 | 94.7% | 45 |
| 17 Jul 2026 | 95.5% | 45 |
Frequently asked questions
What is the current water level of Lake Como and Como Dam (CMO)?
As of July 28, 2026, Lake Como and Como Dam (CMO) is at 83.1% of its capacity, holding approximately 39 hm³ of water, according to BOR RISE (US Bureau of Reclamation) data.
Is Lake Como and Como Dam (CMO) reservoir full?
No. As of July 28, 2026, Lake Como and Como Dam (CMO) is high at 83.1% of its capacity, so it is not full.
Is the water level at Lake Como and Como Dam (CMO) rising or falling?
The level at Lake Como and Como Dam (CMO) has been broadly stable over the latest week on record (-1.4 points).
How much water can Lake Como and Como Dam (CMO) hold?
Lake Como and Como Dam (CMO) has a total capacity of 47 hm³.
Where is Lake Como and Como Dam (CMO) reservoir located?
Lake Como and Como Dam (CMO) is located in Montana, United States, within the Montana basin (coordinates 46.062°N, 114.233°W).
What is Lake Como and Como Dam (CMO) used for?
Lake Como and Como Dam (CMO) is used primarily for multiple purposes, and is managed by BOR.