Gallatin HUC8 10020008
A 4,785 km² sub-basin of the Missouri region in MT, WY. 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
66
Moderate
Drought index
18
Abnormally dry
Area in D2+
0%
0% exceptional (D4)
Gauges below normal
75%
of 4 reporting
Median flow
81%
p23 of record
Water assets
2,141
88 springs · 1,162 wells
USGS gauges (5)
- Gallatin River near Gallatin Gateway, MT06043500355 cfsp18 · below normal
- Hyalite C at Hyalite R S nr Bozeman MT0605000027 cfsp21 · below normal
- Gallatin River at Logan MT06052500593 cfsp24 · below normal
- E Gallatin R ab Water Reclamation Fa nr Bozeman MT06048650100 cfsp83 · above normal
- Gallatin River above Deer Creek, near Big Sky, MT06043120237 cfsno long-term record
Recent conditions
| Date | DSCI | D2+ % | Gauges low | Flow pct |
|---|---|---|---|---|
| 2026-10-19 | 18 | 0 | 3/4 | p23 |
| 2026-10-18 | 18 | 0 | 2/4 | p24 |
| 2026-10-17 | 18 | 0 | 2/4 | p23 |
| 2026-10-16 | 18 | 0 | 2/4 | p28 |
| 2026-10-15 | 91 | 0 | 0/4 | p36 |
| 2026-10-14 | 91 | 0 | 0/4 | p32 |
| 2026-10-13 | 91 | 0 | 1/4 | p39 |
| 2026-10-12 | 91 | 0 | 0/4 | p41 |
| 2026-10-11 | 91 | 0 | 2/4 | p26 |
| 2026-10-10 | 91 | 0 | 2/4 | p17 |
| 2026-10-09 | 91 | 0 | 3/4 | p16 |
| 2026-10-08 | 127 | 0 | 3/4 | p17 |
| 2026-10-07 | 127 | 0 | 2/4 | p24 |
| 2026-10-06 | 127 | 0 | 2/4 | p24 |
Top water assets
- 69Little Wapiti Creekriver
- 69Bridger Creekriver
- 69Tepee Creekriver
- 69Gallatin Riverriver
- 69Wapiti Creekriver
- 69Gallatin River Near Gallatin Gateway, Mtriver
- 69Gallatin River Above Deer Creek, Near Big Sky, Mtriver
- 69Gallatin Riverriver
- 69Hyalite C At Hyalite R S Nr Bozeman Mtriver
- 69North Fork West Fork Gallatin Riverriver