Greys-Hoback HUC8 17040103
A 4,097 km² sub-basin of the Pacific Northwest region in ID, 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
69
Moderate
Drought index
128
Moderate
Area in D2+
0%
0% exceptional (D4)
Gauges below normal
25%
of 8 reporting
Median flow
96%
p40 of record
Water assets
571
133 springs · 196 wells
USGS gauges (8)
- CACHE CREEK NEAR JACKSON, WY130183005 cfsp11 · below normal
- GREYS RIVER ABOVE RESERVOIR, NEAR ALPINE, WY13023000250 cfsp20 · below normal
- HOBACK RIVER NEAR JACKSON, WY13019500238 cfsp34 · normal
- SNAKE RIVER BELOW FLAT CREEK, NEAR JACKSON, WY130187501,510 cfsp37 · normal
- SNAKE RIVER ABOVE RESERVOIR, NEAR ALPINE, WY130225001,860 cfsp42 · normal
- FLAT CREEK BELOW CACHE CREEK, NEAR JACKSON, WY1301835075 cfsp53 · normal
- GRANITE C AB GRANITE C SUPPLEMENTAL, NR MOOSE, WY1301630511 cfsp75 · above normal
- FISH CREEK AT WILSON, WY13016450144 cfsp78 · above normal
Recent conditions
| Date | DSCI | D2+ % | Gauges low | Flow pct |
|---|---|---|---|---|
| 2026-10-19 | 128 | 0 | 2/8 | p40 |
| 2026-10-18 | 128 | 0 | 2/8 | p45 |
| 2026-10-17 | 128 | 0 | 2/8 | p52 |
| 2026-10-16 | 128 | 0 | 1/8 | p64 |
| 2026-10-15 | 136 | 0.18 | 1/8 | p75 |
| 2026-10-14 | 136 | 0.18 | 0/8 | p77 |
| 2026-10-13 | 136 | 0.18 | 0/8 | p77 |
| 2026-10-12 | 136 | 0.18 | 0/8 | p76 |
| 2026-10-11 | 136 | 0.18 | 4/8 | p29 |
| 2026-10-10 | 136 | 0.18 | 4/8 | p20 |
| 2026-10-09 | 136 | 0.18 | 6/8 | p18 |
| 2026-10-08 | 137 | 0.69 | 6/8 | p17 |
| 2026-10-07 | 137 | 0.69 | 4/8 | p19 |
| 2026-10-06 | 137 | 0.69 | 4/8 | p22 |
Top water assets
- 69Flat Creek Below Cache Creek, Near Jackson, Wyriver
- 69Granite C Ab Granite C Supplemental, Nr Moose, Wyriver
- 69Snake Riverriver
- 69Hoback River Near Jackson, Wyriver
- 69Snake Riverriver
- 69Snake River Above Reservoir, Near Alpine, Wyriver
- 69Snake Riverriver
- 69Cache Creek Near Jackson, Wyriver
- 69Snake Riverriver
- 69Fish Creek At Wilson, Wyriver