Shumway Arroyo
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.
- 1Middle San Juan
- river and reservoirs
- gauge
About the Shumway Arroyo
This report follows 21 miles (33 km) of the Shumway Arroyo, all within the Middle San Juan watershed segment. At the lower end of the report the river drains about 142 square miles. Downstream of the mapped reach it flows into the San Juan River. Named tributaries joining it here include the Narrows Wash and Westwater Arroyo. 2 gauges with at least 26 weeks of daily flow cover 1974 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: Middle San Juan
No data last week.
Median conductance 862 µS/cm in the 2010s. Rain over the last 3 months: 239% of normal.
Reservoirs
No reservoir with 500 acre-feet or more of storage on this river in the National Inventory of Dams.
Water users
Surface water withdrawn, 2020
In the counties this river crosses (San Juan): 412,312 acre-feet. County totals include other streams.
| Use | Share (bar) | Share | Acre-ft |
|---|---|---|---|
| Irrigated agriculture | 80% | 330,370 | |
| Power | 8% | 32,474 | |
| Reservoir evaporation | 7% | 27,174 | |
| Public water supply | 5% | 21,357 | |
| Commercial | 0% | 913 |
State Engineer, New Mexico Water Use by Categories 2020.
Public water systems beside the river
Lower Valley Water Users Association
State Engineer's public water systems layer (service areas within 2 km).
Sources
Numbered sources for the statements above, as they were read when the page was prepared.