Big River at Byrnesville, MO
USGS Site No: 07018500 • Big River • Jefferson County, MO
Big River at Byrnesville, MO on the Big River is currently at 363 cfs (High — 77th percentile for this date) . Gage height: 2.98 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 | 112 | |
| 25th | Low threshold | 140 | |
| 50th (Median) | Normal (median) | 181 | |
| 75th | High threshold | 310 | |
| 95th | Very High threshold | 808 | Today: 363 cfs |
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 | 374 | — |
| May 27, 2026 | 383 | — |
| May 26, 2026 | 402 | — |
| May 25, 2026 | 431 | — |
| May 24, 2026 | 462 | — |
| May 23, 2026 | 498 | — |
| May 22, 2026 | 550 | — |
| May 21, 2026 | 663 | — |
| May 20, 2026 | 873 | — |
| May 19, 2026 | 2,300 | — |
| May 18, 2026 | 1,440 | — |
| May 17, 2026 | 456 | — |
| May 16, 2026 | 490 | — |
| May 15, 2026 | 534 | — |
| Apr 20, 2026 | 2,370 | — |
| Apr 19, 2026 | 2,500 | — |
| Apr 18, 2026 | 1,570 | — |
| Apr 17, 2026 | 939 | — |
| Apr 16, 2026 | 854 | — |
| Apr 15, 2026 | 418 | — |
| Apr 14, 2026 | 431 | — |
| Apr 13, 2026 | 455 | — |
| Apr 12, 2026 | 481 | — |
| Apr 11, 2026 | 515 | — |
| Apr 10, 2026 | 563 | — |
| Apr 9, 2026 | 628 | — |
| Apr 8, 2026 | 726 | — |
| Apr 7, 2026 | 871 | — |
| Apr 6, 2026 | 995 | — |
| Apr 5, 2026 | 927 | — |
Station Information
- USGS Site No
- 07018500
- State
- MO
- County
- Jefferson County
- Coordinates
- 38.3917, -90.6378
- Drainage Area
- 917 mi²
- Datum (ft)
- 433.7
- HUC Code
- 07140104
Flood Stage Thresholds
- Action Stage
- 13.0 ft
- Flood Stage
- 16.0 ft
- Moderate Flood
- 20.0 ft
- Major Flood
- 28.0 ft
Currently 13.02 ft below flood stage.
Recent Extremes
- Max discharge
-
19,500 cfsMar 7, 2026
- Min discharge
-
107 cfsSep 17, 2025
- Days at flood stage
- 0
Computed from the local daily-values archive.
Nearby Gauges
-
Bonhomme Creek Near Ellisville, MOHigh15.2 mi · 1 cfs
-
Missouri River Near Labadie, MOVery High16.2 mi · 116,000 cfs
-
Caulks Creek at Chesterfield, MONormal18.3 mi · 13 cfs
-
Bonhomme Creek Near Clarkson Valley, MOHigh18.5 mi · 5 cfs
-
Creve Coeur Creek at Chesterfield, MONormal18.6 mi · 2 cfs