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 2026-09-01); streamflow classes place each USGS gauge's latest reading against its own day-of-year record.
Health score
72
Moderate
Drought index
100
Moderate
Area in D2+
0%
0% exceptional (D4)
Gauges below normal
0%
of 4 reporting
Median flow
343%
p87 of record
Water assets
1,669
42 springs · 702 wells
USGS gauges (9)
- TUALATIN RIVER NEAR DILLEY, OR14203500173 cfsp66 · normal
- TUALATIN RIVER AT WEST LINN, OR14207500340 cfsp84 · above normal
- FANNO CREEK AT 56TH AVE, AT PORTLAND, OR142069001 cfsp89 · above normal
- FANNO CREEK AT DURHAM, OR1420695021 cfsp94 · much 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, OR1420535014 cfsno long-term record
- TUALATIN RIVER AT HWY 219 NEAR HILLSBORO, OR14206241166 cfsno long-term record
- CHICKEN CREEK ABV SEASONAL TRAIL, NR SHERWOOD, OR142067526 cfsno long-term record
Recent conditions
| Date | DSCI | D2+ % | Gauges low | Flow pct |
|---|---|---|---|---|
| 2026-09-07 | 100 | 0 | 0/4 | p87 |
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