Lewis HUC8 17080002
A 2,716 km² sub-basin of the Pacific Northwest region in WA. 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
54
Moderate
Drought index
100
Moderate
Area in D2+
0%
0% exceptional (D4)
Gauges below normal
83%
of 6 reporting
Median flow
36%
p8 of record
Water assets
2,170
269 springs · 804 wells
USGS gauges (6)
- SPEELYAI CREEK NEAR COUGAR, WA142198001 cfsp5 · much below normal
- EAST FORK LEWIS RIVER NEAR HEISSON, WA1422250039 cfsp8 · much below normal
- LEWIS RIVER ABOVE MUDDY RIVER NEAR COUGAR, WA14216000164 cfsp8 · much below normal
- MUDDY RIVER BELOW CLEAR CREEK NEAR COUGAR, WA14216500103 cfsp9 · much below normal
- CANYON CREEK NEAR AMBOY, WA1421900024 cfsp12 · below normal
- LEWIS RIVER AT ARIEL, WA142205002,650 cfsp49 · normal
Recent conditions
| Date | DSCI | D2+ % | Gauges low | Flow pct |
|---|---|---|---|---|
| 2026-10-19 | 100 | 0 | 5/6 | p8 |
| 2026-10-18 | 100 | 0 | 5/6 | p8 |
| 2026-10-17 | 100 | 0 | 5/6 | p9 |
| 2026-10-16 | 100 | 0 | 5/6 | p9 |
| 2026-10-15 | 100 | 0 | 5/6 | p9 |
| 2026-10-14 | 100 | 0 | 5/6 | p9 |
| 2026-10-13 | 100 | 0 | 5/6 | p10 |
| 2026-10-12 | 100 | 0 | 5/6 | p11 |
| 2026-10-11 | 100 | 0 | 4/6 | p14 |
| 2026-10-10 | 100 | 0 | 4/6 | p13 |
| 2026-10-09 | 100 | 0 | 4/6 | p10 |
| 2026-10-08 | 100 | 0 | 4/6 | p10 |
| 2026-10-07 | 100 | 0 | 4/6 | p10 |
| 2026-10-06 | 100 | 0 | 4/6 | p11 |
Top water assets
- 76Ir — Ce S2-*11791Cwrisspring
- 76Ir St — Ce S2-21907Alcwrisspring
- 76Fp Ir — Ap S2-28836spring
- 76Fs — Ap S2-30553spring
- 76Fs — Ap S2-30556spring
- 76Fs — Ap S2-30414spring
- 76Ir — Ce S2-25465Gwrisspring
- 76Po — Ap S2-28278spring
- 76Ci Ir — Ce S2-*20093Cwrisspring
- 73Ir — Ce S2-25912Gwrisspring