Reservoir · Utah · United States · BOR RISE
Moon Lake Reservoir
Moon Lake Reservoir and Dam
18.2% full
Capacity
61.06 hm³
Volume stored
11 hm³
Coordinates
40.574°N, 110.507°W
Last updated
2026-09-09
Current fill
18.2%vs 7 days ago
-1.3%losing
vs 1 year ago
+6.5%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: 2026-09-09.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 40.574, -110.507 · Open in Google Maps
About Moon Lake Reservoir
As of September 9, 2026, Moon Lake Reservoir is filled to 18.2% of its total capacity, holding roughly 11 hm³ of water out of a maximum 61 hm³. At this level the reservoir is critically low.
Over the most recent week on record the fill level has held broadly steady (-1.3 pts), and it is 6.5 points above its level on the same date a year earlier.
Across the readings we hold for Moon Lake Reservoir — 1824 data points between September 12, 2021 and September 9, 2026 — the level has ranged from a low of 10.8% (September 15, 2025) to a high of 77.8% (June 19, 2023). On average the reservoir is fullest around June and at its lowest around September.
It is operated by BOR primarily for multiple purposes. It lies within the Utah basin at 40.574°N, 110.507°W.
Key facts
- Current fill level
- 18.2%
- Water stored
- 11 hm³
- Total capacity
- 61 hm³
- 7-day change
- ▼ 1.3 pts
- Year-on-year
- ▲ 6.5 pts
- Primary use
- Multipurpose
- River basin
- Utah
- Operator
- BOR
- Coordinates
- 40.574°N, 110.507°W
- Last updated
- September 9, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 9 Sep 2026 | 18.2% | 11 |
| 8 Sep 2026 | 18.3% | 11 |
| 7 Sep 2026 | 18.2% | 11 |
| 6 Sep 2026 | 18.2% | 11 |
| 5 Sep 2026 | 18.5% | 11 |
| 4 Sep 2026 | 18.9% | 12 |
| 3 Sep 2026 | 19.2% | 12 |
| 2 Sep 2026 | 19.5% | 12 |
| 1 Sep 2026 | 19.7% | 12 |
| 31 Aug 2026 | 19.9% | 12 |
| 30 Aug 2026 | 20.1% | 12 |
| 29 Aug 2026 | 20.0% | 12 |