Flatwillow HUC8 10040203
A 1,761 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
53
Moderate
Drought index
204
Severe
Area in D2+
8.43%
0% exceptional (D4)
Gauges below normal
100%
of 1 reporting
Median flow
0%
p10 of record
Water assets
351
2 springs · 24 wells
USGS gauges (1)
- Flatwillow Creek near Mosby MT061300000 cfsp10 · below normal
Recent conditions
| Date | DSCI | D2+ % | Gauges low | Flow pct |
|---|---|---|---|---|
| 2026-09-07 | 204 | 8.43 | 1/1 | p10 |
Top water assets
- 69Half Moon Creekriver
- 69North Fork Flatwillow Creekriver
- 69North Fork Flatwillow Creekriver
- 69McCartney Creekriver
- 69North Fork Flatwillow Creekriver
- 69South Fork Flatwillow Creekriver
- 69South Fork Flatwillow Creekriver
- 69South Fork Flatwillow Creekriver
- 69North Fork Flatwillow Creekriver
- 69Maynard Creekriver