Reservoir · Montana · United States · USACE CWMS
Nelson Reservoir nr Saco, MT
52.9% full
Capacity
97.72 hm³
Volume stored
52 hm³
Coordinates
48.530°N, 107.519°W
Last updated
2026-06-11
Current fill
52.9%vs 7 days ago
-0.4%losing
vs 1 year ago
-20.1%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. 48.530, -107.519 · Open in Google Maps
About Nelson Reservoir nr Saco, MT
As of June 11, 2026, Nelson Reservoir nr Saco, MT is filled to 52.9% of its total capacity, holding roughly 52 hm³ of water out of a maximum 98 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 (-0.4 pts), and it is 20.1 points below its level on the same date a year earlier.
Across the readings we hold for Nelson Reservoir nr Saco, MT — 1822 data points between June 13, 2021 and June 11, 2026 — the level has ranged from a low of 39.8% (July 27, 2021) to a high of 99.3% (May 3, 2024). On average the reservoir is fullest around May and at its lowest around February.
It is operated by USACE primarily for multiple purposes. It lies within the Montana basin at 48.530°N, 107.519°W.
Key facts
- Current fill level
- 52.9%
- Water stored
- 52 hm³
- Total capacity
- 98 hm³
- 7-day change
- ▼ 0.4 pts
- Year-on-year
- ▼ 20.1 pts
- Primary use
- Multipurpose
- River basin
- Montana
- Operator
- USACE
- Coordinates
- 48.530°N, 107.519°W
- Last updated
- June 11, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 11 Jun 2026 | 52.9% | 52 |
| 10 Jun 2026 | 53.3% | 52 |
| 9 Jun 2026 | 53.6% | 52 |
| 8 Jun 2026 | 54.0% | 53 |
| 7 Jun 2026 | 54.5% | 53 |
| 6 Jun 2026 | 54.5% | 53 |
| 5 Jun 2026 | 54.9% | 54 |
| 4 Jun 2026 | 55.2% | 54 |
| 3 Jun 2026 | 55.5% | 54 |
| 2 Jun 2026 | 56.2% | 55 |
| 1 Jun 2026 | 57.1% | 56 |
| 31 May 2026 | 57.7% | 56 |
Frequently asked questions
What is the current water level of Nelson Reservoir nr Saco, MT?
As of June 11, 2026, Nelson Reservoir nr Saco, MT is at 52.9% of its capacity, holding approximately 52 hm³ of water, according to USACE CWMS (US Army Corps of Engineers) data.
Is Nelson Reservoir nr Saco, MT reservoir full?
No. As of June 11, 2026, Nelson Reservoir nr Saco, MT is within its normal operating range at 52.9% of its capacity, so it is not full.
Is the water level at Nelson Reservoir nr Saco, MT rising or falling?
The level at Nelson Reservoir nr Saco, MT has been broadly stable over the latest week on record (-0.4 points).
How much water can Nelson Reservoir nr Saco, MT hold?
Nelson Reservoir nr Saco, MT has a total capacity of 98 hm³.
Where is Nelson Reservoir nr Saco, MT reservoir located?
Nelson Reservoir nr Saco, MT is located in Montana, United States, within the Montana basin (coordinates 48.530°N, 107.519°W).
What is Nelson Reservoir nr Saco, MT used for?
Nelson Reservoir nr Saco, MT is used primarily for multiple purposes, and is managed by USACE.