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 2026-10-13); streamflow classes place each USGS gauge's latest reading against its own day-of-year record.
Health score
86
Healthy
Drought index
0
None
Area in D2+
0%
0% exceptional (D4)
Gauges below normal
0%
of 1 reporting
Median flow
97%
p47 of record
Water assets
431
38 springs · 73 wells
USGS gauges (1)
- Boulder River near Boulder, MT0603300035 cfsp47 · normal
Recent conditions
| Date | DSCI | D2+ % | Gauges low | Flow pct |
|---|---|---|---|---|
| 2026-10-21 | 0 | 0 | 0/1 | p47 |
| 2026-10-20 | 0 | 0 | 0/1 | p54 |
| 2026-10-19 | 0 | 0 | 0/1 | p54 |
| 2026-10-18 | 0 | 0 | 0/1 | p51 |
| 2026-10-17 | 0 | 0 | 0/1 | p49 |
| 2026-10-16 | 0 | 0 | 0/1 | p51 |
| 2026-10-15 | 0 | 0 | 0/1 | p49 |
| 2026-10-14 | 0 | 0 | 0/1 | p42 |
| 2026-10-13 | 0 | 0 | 0/1 | p39 |
| 2026-10-12 | 0 | 0 | 0/1 | p33 |
| 2026-10-11 | 0 | 0 | 0/1 | p30 |
| 2026-10-10 | 0 | 0 | 1/1 | p24 |
| 2026-10-09 | 0 | 0 | 1/1 | p24 |
| 2026-10-08 | 100 | 0 | 0/1 | p26 |
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