Reservoir · Colorado · United States · BOR RISE
Green Mountain Reservoir
Green Mountain Reservoir Dam and Powerplant
9.3% full
Capacity
189.51 hm³
Volume stored
18 hm³
Vs month average
19% of normal
Coordinates
39.879°N, 106.313°W
Last updated
2026-10-27
Current fill
9.3%vs 7 days ago
-0.4 pplosing
vs 1 year ago
-33.1 ppyear-over-year
7-day trend
→stable
Drought context
Storage vs October average
19%of normal
9.3% full on 2026-10-27, against an average of 49.4% for October across 6 years of readings (-40.1 points).
Drought Monitor at this site · 20 October 2026
D4exceptional drought
The ground at Green Mountain Reservoir's coordinates falls inside the D4 area of the weekly U.S. Drought Monitor map. That describes local conditions — rainfall, soil moisture, streamflow — not the reservoir's storage. Colorado drought figures →
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: 2026-10-27.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 39.879°N, 106.313°W · Open in Google Maps
About Green Mountain Reservoir
As of October 27, 2026, Green Mountain Reservoir is filled to 9.3% of its total capacity, holding 17.7 hm³ of water out of a maximum 189.51 hm³. At this level the reservoir is critically low.
Over the most recent week on record the fill level has held broadly steady (-0.4 pp), and it is 33.1 points below its level on the same date a year earlier.
Across the readings we hold for Green Mountain Reservoir — 1951 data points between October 29, 2021 and October 27, 2026 — the level has ranged from a low of 9.3% (October 27, 2026) to a high of 99.4% (July 21, 2023). On average the reservoir is fullest around July and at its lowest around April.
It is operated by BOR primarily for multiple purposes. It is at 39.879°N, 106.313°W.
Key facts
- Current fill level
- 9.3% of total capacity
- Water stored
- 17.7 hm³
- Total capacity
- 189.51 hm³
- 7-day change
- ▼ 0.4 pp
- Year-on-year
- ▼ 33.1 pp
- Primary use
- Multipurpose
- Operator
- BOR
- Coordinates
- 39.879°N, 106.313°W
- Last updated
- October 27, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 27 Oct 2026 | 9.3% | 17.7 |
| 26 Oct 2026 | 9.4% | 17.73 |
| 25 Oct 2026 | 9.4% | 17.82 |
| 24 Oct 2026 | 9.5% | 17.95 |
| 23 Oct 2026 | 9.5% | 18.09 |
| 22 Oct 2026 | 9.6% | 18.2 |
| 21 Oct 2026 | 9.7% | 18.3 |
| 20 Oct 2026 | 9.7% | 18.42 |
| 19 Oct 2026 | 9.8% | 18.55 |
| 18 Oct 2026 | 9.9% | 18.71 |
| 17 Oct 2026 | 10.0% | 18.86 |
| 16 Oct 2026 | 10.0% | 19.01 |