Castor River at Zalma, MO
USGS Site No: 07021000 • Castor River • Bollinger County, MO
Castor River at Zalma, MO on the Castor River is currently at 147 cfs (Normal — 40th percentile for this date) . Gage height: 1.76 ft.
Reading from
Historical Percentile Comparison
Today's discharge compared to the long-term record for June 11 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 | 74 | |
| 25th | Low threshold | 103 | |
| 50th (Median) | Normal (median) | 177 | Today: 147 cfs |
| 75th | High threshold | 347 | |
| 95th | Very High threshold | 1,730 |
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 | 152 | — |
| May 27, 2026 | 141 | — |
| May 26, 2026 | 133 | — |
| May 25, 2026 | 136 | — |
| May 24, 2026 | 139 | — |
| May 23, 2026 | 135 | — |
| May 22, 2026 | 130 | — |
| May 21, 2026 | 129 | — |
| May 20, 2026 | 132 | — |
| May 17, 2026 | 145 | — |
| May 16, 2026 | 149 | — |
| May 15, 2026 | 156 | — |
| Apr 20, 2026 | 808 | — |
| Apr 19, 2026 | 961 | — |
| Apr 18, 2026 | 535 | — |
| Apr 17, 2026 | 389 | — |
| Apr 16, 2026 | 304 | — |
| Apr 15, 2026 | 285 | — |
| Apr 14, 2026 | 308 | — |
| Apr 13, 2026 | 334 | — |
| Apr 12, 2026 | 365 | — |
| Apr 11, 2026 | 404 | — |
| Apr 10, 2026 | 429 | — |
| Apr 9, 2026 | 479 | — |
| Apr 8, 2026 | 550 | — |
| Apr 7, 2026 | 663 | — |
| Apr 6, 2026 | 897 | — |
| Apr 5, 2026 | 1,140 | — |
| Apr 4, 2026 | 276 | — |
| Apr 3, 2026 | 210 | — |
Station Information
- USGS Site No
- 07021000
- State
- MO
- County
- Bollinger County
- Coordinates
- 37.1466, -90.0755
- Drainage Area
- 423 mi²
- Datum (ft)
- 350.5
- HUC Code
- 07140107
Recent Extremes
- Max discharge
-
8,440 cfsMar 6, 2026
- Min discharge
-
68 cfsSep 19, 2025
Computed from the local daily-values archive.
Nearby Gauges
-
St. Francis River at Wappapello, MONormal18.4 mi · 587 cfs
-
St. Francis River Near Patterson, MONormal23.8 mi · 372 cfs
-
Big Creek at Sam at Baker State Park, MONormal25.0 mi · 76 cfs
-
St. Francis River at Fisk, MOLow26.3 mi · 200 cfs
-
St. Francis River Near Saco, MOLow27.4 mi · 100 cfs