Boulder HUC8 10020006
A 1,966 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
79
Healthy
Drought index
101
Moderate
Area in D2+
0%
0% exceptional (D4)
Gauges below normal
0%
of 1 reporting
Median flow
116%
p57 of record
Water assets
431
38 springs · 73 wells
USGS gauges (1)
- Boulder River near Boulder, MT0603300023 cfsp57 · normal
Recent conditions
| Date | DSCI | D2+ % | Gauges low | Flow pct |
|---|---|---|---|---|
| 2026-09-07 | 101 | 0 | 0/1 | p57 |
Top water assets
- 69Boulder Riverriver
- 69North Fork Red Rock Creekriver
- 69Red Rock Creekriver
- 69Bison Creekriver
- 69Bison Creekriver
- 69Bison Creekriver
- 69North Fork Little Boulder Riverriver
- 69Dry Creekriver
- 69Boulder Riverriver
- 69Lowland Creekriver