Ruby HUC8 10020003
A 2,501 km² sub-basin of the Missouri region in MT. Drought coverage is from the US Drought Monitor (map of 2026-09-01); streamflow classes place each USGS gauge's latest reading against its own day-of-year record.
Health score
61
Moderate
Drought index
200
Severe
Area in D2+
0%
0% exceptional (D4)
Gauges below normal
67%
of 3 reporting
Median flow
83%
p18 of record
Water assets
662
11 springs · 45 wells
USGS gauges (3)
- Ruby River near Twin Bridges MT0602300095 cfsp10 · below normal
- Ruby River above reservoir near Alder, MT0601950088 cfsp18 · below normal
- Ruby River below reservoir near Alder, MT06020600265 cfsp49 · normal
Recent conditions
| Date | DSCI | D2+ % | Gauges low | Flow pct |
|---|---|---|---|---|
| 2026-09-07 | 200 | 0 | 2/3 | p18 |
Top water assets
- 69Sweetwater Creekriver
- 69Cottonwood Creekriver
- 69Ledford Creekriver
- 69North Fork Greenhorn Creekriver
- 69Ledford Creekriver
- 69Ruby River Above Reservoir Near Alder, Mtriver
- 69East Fork Ruby Riverriver
- 69Ruby Riverriver
- 69Ruby River Below Reservoir Near Alder, Mtriver
- 69Mill Creekriver