Manalapan Brook at Spotswood NJ
USGS Site No: 01405400 • Manalapan Brook • Middlesex County, NJ
Manalapan Brook at Spotswood NJ on the Manalapan Brook is currently at 27 cfs (Normal — 36th percentile for this date) . Gage height: 10.00 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 | 18 | |
| 25th | Low threshold | 23 | |
| 50th (Median) | Normal (median) | 33 | Today: 27 cfs |
| 75th | High threshold | 47 | |
| 95th | Very High threshold | 126 |
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 | 40 | — |
| May 27, 2026 | 45 | — |
| May 26, 2026 | 68 | — |
| May 24, 2026 | 84 | — |
| May 23, 2026 | 26 | — |
| May 21, 2026 | 26 | — |
| May 20, 2026 | 16 | — |
| May 19, 2026 | 16 | — |
| May 18, 2026 | 17 | — |
| May 17, 2026 | 19 | — |
| May 15, 2026 | 22 | — |
| Apr 21, 2026 | 23 | — |
| Apr 19, 2026 | 23 | — |
| Apr 18, 2026 | 24 | — |
| Apr 17, 2026 | 25 | — |
| Apr 14, 2026 | 31 | — |
| Apr 12, 2026 | 27 | — |
| Apr 10, 2026 | 28 | — |
| Apr 8, 2026 | 35 | — |
| Apr 7, 2026 | 44 | — |
| Apr 4, 2026 | 36 | — |
| Apr 3, 2026 | 37 | — |
| Mar 31, 2026 | 33 | — |
| Mar 30, 2026 | 33 | — |
| Mar 29, 2026 | 35 | — |
| Mar 28, 2026 | 40 | — |
| Mar 27, 2026 | 41 | — |
| Mar 26, 2026 | 40 | — |
| Mar 24, 2026 | 53 | — |
| Mar 23, 2026 | 53 | — |
Station Information
- USGS Site No
- 01405400
- State
- NJ
- County
- Middlesex County
- Coordinates
- 40.3894, -74.3906
- Drainage Area
- 41 mi²
- Datum (ft)
- -1.2
- HUC Code
- 020301050401
Flood Stage Thresholds
- Action Stage
- 18.5 ft
- Flood Stage
- 19.0 ft
- Moderate Flood
- 21.0 ft
- Major Flood
- 22.0 ft
Currently 9.00 ft below flood stage.
Recent Extremes
- Max discharge
-
382 cfsMar 7, 2026
- Min discharge
-
7 cfsOct 6, 2025
- Days at flood stage
- 0
Computed from the local daily-values archive.
Nearby Gauges
-
Robinsons Branch at Rahway NJNormal15.7 mi · 7 cfs
-
Robinsons Branch at Maple Ave at Rahway NJLow15.9 mi · 1 cfs
-
Rahway River at Rahway NJNormal16.8 mi · 17 cfs
-
Rahway River Near Springfield NJNormal21.0 mi · 12 cfs
-
Passaic River Near Millington NJNormal21.4 mi · 27 cfs