Upper Missouri-Dearborn HUC8 10030102
A 6,737 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
77
Healthy
Drought index
0
None
Area in D2+
0%
0% exceptional (D4)
Gauges below normal
33%
of 6 reporting
Median flow
85%
p30 of record
Water assets
2,300
107 springs · 433 wells
USGS gauges (6)
- Missouri River bl Holter Dam nr Wolf Cr MT060665002,950 cfsp10 · much below normal
- Missouri River near Great Falls MT060903004,120 cfsp17 · below normal
- Missouri River near Ulm MT060782003,630 cfsp28 · normal
- Missouri River at Cascade MT060740003,390 cfsp33 · normal
- Missouri River at Fort Benton MT060908004,580 cfsp38 · normal
- Dearborn River near Craig MT0607350069 cfsp61 · normal
Recent conditions
| Date | DSCI | D2+ % | Gauges low | Flow pct |
|---|---|---|---|---|
| 2026-10-19 | 0 | 0 | 2/6 | p30 |
| 2026-10-18 | 0 | 0 | 2/6 | p31 |
| 2026-10-17 | 0 | 0 | 3/6 | p28 |
| 2026-10-16 | 0 | 0 | 2/6 | p25 |
| 2026-10-15 | 0 | 0 | 1/6 | p35 |
| 2026-10-14 | 0 | 0 | 1/6 | p37 |
| 2026-10-13 | 0 | 0 | 1/6 | p33 |
| 2026-10-12 | 0 | 0 | 1/6 | p34 |
| 2026-10-11 | 0 | 0 | 1/6 | p28 |
| 2026-10-10 | 0 | 0 | 4/6 | p18 |
| 2026-10-09 | 0 | 0 | 4/6 | p21 |
| 2026-10-08 | 0 | 0 | 3/6 | p18 |
| 2026-10-07 | 0 | 0 | 3/6 | p20 |
| 2026-10-06 | 0 | 0 | 3/6 | p21 |
Top water assets
- 74Kootenai Formation Aquifer — Great Falls Regionaquifer
- 69Dearborn Riverriver
- 69West Fork Falls Creekriver
- 69Whitetail Creekriver
- 69Whitetail Creekriver
- 69Dearborn Riverriver
- 69East Fork Falls Creekriver
- 69Dearborn Riverriver
- 69Dearborn Riverriver
- 69West Fork Falls Creekriver