Alamosa River
Streamflow, conditions and background by watershed segment. Data through November 1, 2026.
Where it is
Segments are the HUC8 watersheds the gauges sit in, numbered upstream to downstream. Use the buttons to switch between the state and the river.
- 1Alamosa-Trinchera
- river and reservoirs
- gauge
About the Alamosa River
This report follows 61 miles (98 km) of the Alamosa River, all within the Alamosa-Trinchera watershed segment. At the lower end of the report the river drains about 187 square miles. Downstream of the mapped reach it flows into the Rock Creek. Reservoirs on this reach: Terrace Reservoir. Largest urban areas near it: Alamosa. 6 gauges with at least 26 weeks of daily flow cover 1914 to 2026.
From the archive: NHDPlus river network, WBD watersheds, NHD waterbodies, TIGER urban areas and the report's gauges.
From the headwaters down
Each watershed segment in order, with last week's flow rated against the same week in 1991–2020.
Segment 1: Alamosa-Trinchera
260 cfs last week much above normal.
Median conductance 226 µS/cm in the 2010s. Rain over the last 3 months: 198% of normal.
Reservoirs
| Reservoir | Completed | Main purpose | Storage, acre-ft |
|---|---|---|---|
| Terrace | 1912 | Irrigation | 19,195 |
From the archive: National Inventory of Dams (USACE) and the reservoir registry.
Sources
Numbered sources for the statements above, as they were read when the page was prepared.