Floyd River at Alton, IA
USGS Site No: 06600100 • Floyd River • Sioux County, IA
Floyd River at Alton, IA on the Floyd River is currently at 278 cfs (Very High — 99th percentile for this date) . Gage height: 6.92 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 | 2 | |
| 25th | Low threshold | 8 | |
| 50th (Median) | Normal (median) | 17 | |
| 75th | High threshold | 59 | |
| 95th | Very High threshold | 201 |
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 | 332 | — |
| May 27, 2026 | 405 | — |
| May 26, 2026 | 471 | — |
| May 25, 2026 | 369 | — |
| May 24, 2026 | 369 | — |
| May 23, 2026 | 271 | — |
| May 22, 2026 | 166 | — |
| May 21, 2026 | 128 | — |
| May 20, 2026 | 134 | — |
| May 19, 2026 | 133 | — |
| May 18, 2026 | 115 | — |
| May 17, 2026 | 72 | — |
| May 16, 2026 | 60 | — |
| May 15, 2026 | 64 | — |
| Apr 20, 2026 | 117 | — |
| Apr 19, 2026 | 122 | — |
| Apr 18, 2026 | 132 | — |
| Apr 17, 2026 | 143 | — |
| Apr 16, 2026 | 147 | — |
| Apr 15, 2026 | 152 | — |
| Apr 14, 2026 | 158 | — |
| Apr 13, 2026 | 170 | — |
| Apr 12, 2026 | 178 | — |
| Apr 11, 2026 | 179 | — |
| Apr 10, 2026 | 190 | — |
| Apr 9, 2026 | 212 | — |
| Apr 8, 2026 | 230 | — |
| Apr 7, 2026 | 244 | — |
| Apr 6, 2026 | 272 | — |
| Apr 5, 2026 | 298 | — |
Station Information
- USGS Site No
- 06600100
- State
- IA
- County
- Sioux County
- Coordinates
- 42.9828, -96.0003
- Drainage Area
- 268 mi²
- Datum (ft)
- 1,270.2
- HUC Code
- 10230002
Flood Stage Thresholds
- Action Stage
- 10.0 ft
- Flood Stage
- 12.0 ft
- Moderate Flood
- 16.0 ft
- Major Flood
- 22.0 ft
Currently 5.08 ft below flood stage.
Recent Extremes
- Max discharge
-
2,000 cfsJul 31, 2025
- Min discharge
-
18 cfsJan 17, 2026
- Days at flood stage
- 0
Computed from the local daily-values archive.
Nearby Gauges
-
West Branch Floyd River Near Struble, IAVery High9.8 mi · 159 cfs
-
Rock River Near Rock Valley, IAHigh21.9 mi · 794 cfs
-
Big Sioux River Near Hawarden, IANormal25.2 mi · 1,250 cfs
-
Perry Creek Near Millnerville, IANormal27.4 mi · 3 cfs
-
Big Sioux River at Akron, IAHigh30.1 mi · 1,430 cfs