Reservoir · Colorado · United States · BOR RISE
Horsetooth Reservoir
Horsetooth Reservoir and Dam
73.2% full
Capacity
193.33 hm³
Volume stored
142 hm³
Coordinates
40.599°N, 105.171°W
Last updated
2026-09-09
Current fill
73.2%vs 7 days ago
+1.3%gaining
vs 1 year ago
+13.4%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. 40.599, -105.171 · Open in Google Maps
About Horsetooth Reservoir
As of September 9, 2026, Horsetooth Reservoir is filled to 73.2% of its total capacity, holding roughly 142 hm³ of water out of a maximum 193 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 (+1.3 pts), and it is 13.4 points above its level on the same date a year earlier.
Across the readings we hold for Horsetooth Reservoir — 1950 data points between September 12, 2021 and September 9, 2026 — the level has ranged from a low of 49.5% (December 19, 2022) to a high of 99.6% (June 28, 2024). On average the reservoir is fullest around June and at its lowest around November.
It is operated by BOR primarily for multiple purposes. It lies within the Colorado basin at 40.599°N, 105.171°W.
Key facts
- Current fill level
- 73.2%
- Water stored
- 142 hm³
- Total capacity
- 193 hm³
- 7-day change
- ▲ 1.3 pts
- Year-on-year
- ▲ 13.4 pts
- Primary use
- Multipurpose
- River basin
- Colorado
- Operator
- BOR
- Coordinates
- 40.599°N, 105.171°W
- Last updated
- September 9, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 9 Sep 2026 | 73.2% | 141 |
| 8 Sep 2026 | 72.9% | 141 |
| 7 Sep 2026 | 72.7% | 141 |
| 6 Sep 2026 | 72.4% | 140 |
| 5 Sep 2026 | 72.1% | 139 |
| 4 Sep 2026 | 71.9% | 139 |
| 3 Sep 2026 | 71.7% | 139 |
| 2 Sep 2026 | 71.9% | 139 |
| 1 Sep 2026 | 72.1% | 139 |
| 31 Aug 2026 | 72.2% | 140 |
| 30 Aug 2026 | 72.4% | 140 |
| 29 Aug 2026 | 72.4% | 140 |