Tualatin HUC8 17090010
A 1,836 km² sub-basin of the Pacific Northwest region in OR. 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
64
Moderate
Drought index
100
Moderate
Area in D2+
0%
0% exceptional (D4)
Gauges below normal
50%
of 4 reporting
Median flow
91%
p36 of record
Water assets
1,669
42 springs · 702 wells
USGS gauges (9)
- FANNO CREEK AT DURHAM, OR142069503 cfsp7 · much below normal
- FANNO CREEK AT 56TH AVE, AT PORTLAND, OR142069000 cfsp12 · below normal
- TUALATIN RIVER AT WEST LINN, OR14207500213 cfsp61 · normal
- TUALATIN RIVER NEAR DILLEY, OR14203500170 cfsp79 · above normal
- WAPATO CREEK AT SW GASTON ROAD, AT GASTON, OR142026502 cfsno long-term record
- SCOGGINS CK BLW HENRY HAGG LAKE, NR GASTON, OR14202980147 cfsno long-term record
- EF DAIRY CR ABV MURTAUGH CR NR MEACHAM CORNER, OR142053507 cfsno long-term record
- TUALATIN RIVER AT HWY 219 NEAR HILLSBORO, OR14206241123 cfsno long-term record
- CHICKEN CREEK ABV SEASONAL TRAIL, NR SHERWOOD, OR142067521 cfsno long-term record
Recent conditions
| Date | DSCI | D2+ % | Gauges low | Flow pct |
|---|---|---|---|---|
| 2026-10-18 | 100 | 0 | 2/4 | p36 |
| 2026-10-17 | 100 | 0 | 2/4 | p35 |
| 2026-10-16 | 100 | 0 | 2/4 | p37 |
| 2026-10-15 | 100 | 0 | 2/4 | p39 |
| 2026-10-14 | 100 | 0 | 2/4 | p38 |
| 2026-10-13 | 100 | 0 | 2/4 | p37 |
| 2026-10-12 | 100 | 0 | 2/4 | p42 |
| 2026-10-11 | 100 | 0 | 1/4 | p43 |
| 2026-10-10 | 100 | 0 | 1/4 | p51 |
| 2026-10-09 | 100 | 0 | 2/4 | p40 |
| 2026-10-08 | 100 | 0 | 2/4 | p44 |
| 2026-10-07 | 100 | 0 | 2/4 | p43 |
| 2026-10-06 | 100 | 0 | 2/4 | p46 |
| 2026-10-05 | 100 | 0 | 2/4 | p44 |
Top water assets
- 76Unnamed Stream — Agriculture Usesspring
- 76Buxton Creek — Industrial/Manufacturing Usesspring
- 73A Well — Irrigationwell
- 73Well 3 — Irrigationwell
- 73Well 2 — Nursery Useswell
- 73A Well — Irrigationwell
- 67Scoggins Creekriver
- 67Scoggins Damreservoir
- 67Maple Creekriver
- 67Maple Creekriver