Tualatin River Near Dilley, OR
USGS Site No: 14203500 • Tualatin River • Washington County, OR
Tualatin River Near Dilley, OR on the Tualatin River is currently at 109 cfs (Normal — 46th percentile for this date) . Gage height: 10.21 ft.
Reading from
Historical Percentile Comparison
Today's discharge compared to the long-term record for October 28 at this station. Percentile rank shows what fraction of historical years had lower flow on this date.
| Percentile | Label | CFS Threshold | Today's Flow |
|---|---|---|---|
| 10th | Very Low threshold | 40 | |
| 25th | Low threshold | 65 | |
| 50th (Median) | Normal (median) | 117 | Today: 109 cfs |
| 75th | High threshold | 164 | |
| 95th | Very High threshold | 390 |
30-Day Hydrograph
Recent discharge plotted against the historical 10th–95th percentile envelope for the same calendar days. Source: USGS daily values + long-term statistics.
30-Day Flow History
| Date | Discharge (CFS) | Gage Ht (ft) |
|---|---|---|
| May 28, 2026 | 120 | — |
| May 27, 2026 | 127 | — |
| May 26, 2026 | 139 | — |
| May 25, 2026 | 138 | — |
| May 24, 2026 | 139 | — |
| May 23, 2026 | 138 | — |
| May 22, 2026 | 104 | — |
| May 21, 2026 | 99 | — |
| May 20, 2026 | 97 | — |
| May 19, 2026 | 99 | — |
| May 18, 2026 | 106 | — |
| May 17, 2026 | 116 | — |
| May 16, 2026 | 120 | — |
| May 15, 2026 | 102 | — |
| Apr 20, 2026 | 230 | — |
| Apr 19, 2026 | 258 | — |
| Apr 18, 2026 | 296 | — |
| Apr 17, 2026 | 409 | — |
| Apr 16, 2026 | 541 | — |
| Apr 15, 2026 | 423 | — |
| Apr 14, 2026 | 198 | — |
| Apr 13, 2026 | 172 | — |
| Apr 12, 2026 | 156 | — |
| Apr 11, 2026 | 155 | — |
| Apr 10, 2026 | 128 | — |
| Apr 9, 2026 | 139 | — |
| Apr 8, 2026 | 149 | — |
| Apr 7, 2026 | 160 | — |
| Apr 6, 2026 | 173 | — |
| Apr 5, 2026 | 183 | — |
Station Information
- USGS Site No
- 14203500
- State
- OR
- County
- Washington County
- Coordinates
- 45.4748, -123.1243
- Drainage Area
- 125 mi²
- Datum (ft)
- 147.6
- HUC Code
- 17090010
Flood Stage Thresholds
- Action Stage
- 16.0 ft
- Flood Stage
- 17.5 ft
- Moderate Flood
- 18.5 ft
- Major Flood
- 19.5 ft
Currently 7.29 ft below flood stage.
Recent Extremes
- Max discharge
-
2,660 cfsDec 19, 2025
- Min discharge
-
62 cfsOct 31, 2025
- Days at flood stage
- 0
Computed from the local daily-values archive.
Nearby Gauges
-
Wapato Creek at Sw Gaston Road, at Gaston, ORVery High2.4 mi · 4 cfs
-
Scoggins Ck below Henry Hagg Lake, near Gaston, ORHigh3.7 mi · 147 cfs
-
Tualatin River at Highway 219 Near Hillsboro, ORNormal6.7 mi · 193 cfs
-
Chicken Creek above Seasonal Trail, near Sherwood, ORLow15.2 mi · 0 cfs
-
Willamette River at Newberg, ORNormal15.3 mi · 10,400 cfs