Manalapan Brook At Spotswood flow report
As of July 13, 2026, Manalapan Brook At Spotswood is flowing at 28 cfs with a gage height of 9.98 ft, receding 36% over the past 24 hours. Source: USGS gauge #01405400, refreshed throughout the day.
Historical Data
Manalapan Brook At Spotswood at a glance
How Manalapan Brook At Spotswood is running right now, where it sits on the map, and the key gauge stats.
Manalapan Brook At Spotswood is flowing at 28 cfs, with the water sitting 9.98 ft at the gage. Flow is down 36% since yesterday as the gauge recedes.
This is USGS gauge #01405400 in New Jersey. Over the past 10 days the average has been 50 cfs, peaking at 105 cfs.
Over the next 5 days, Manalapan Brook At Spotswood Nj is expected to recede from today's 28 cfs, toward roughly 22 cfs by 2026-07-18 (likely range 10-49 cfs) -- drier than normal for the date.
For real-time updates and historical context, see the realtime view or the historical comparison. Browse other gauges in the New Jersey flow report.
Streamflow Forecast
Powered by PULSE — Snoflo’s Predictive Unified Learning & Simulation Engine, which learns from how this river has answered every past storm, snowmelt, and dry spell to forecast where it’s headed with a precision generic models can’t match.
How does this compare to past years?
Year-over-year overlay, annual peak discharge, the full distribution of daily flows on record, and the gauge's rating curve.
Weather Forecast
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day forecast
Daily temperatures, snow, and rain projected over the next two weeks.
Manalapan Brook At Spotswood
The stream's flow is mainly provided by precipitation, groundwater runoff, and irrigation return flow. The brook is fed by several smaller tributaries, including Helmetta Creek and Matchaponix Brook. There are no major dams on the brook. Seasonal trends show that the brook's flow is highest in late winter and spring and lowest in late summer and fall. The hydrology of the Manalapan Brook is significant because it is a major source of water for the towns it passes through. Interesting fact: The Manalapan Brook was once known as "the best trout stream in New Jersey."
Nearby streamflow levels
Cross-check Manalapan Brook At Spotswood's discharge against nearby gauges to spot whether the change here is local or regional.
| Gauge | Streamflow |
|---|---|
| Manalapan Brook At Spotswood Nj | 28 cfs |
| Deep Run At Old Bridge Nj | 9 cfs |
| Lawrence Bk At Westons Mills Nj | 28 cfs |
| Big Brook Near Marlboro Nj | 4 cfs |
| Millstone River At Blackwells Mills Nj | 201 cfs |
| Delaware And Raritan Canal At Kingston Nj | 114 cfs |
Nearby snowpack data
Snowpack at SNOTEL stations near Manalapan Brook At Spotswood. Spring snowmelt is the dominant driver of streamflow in mountain basins -- a deep snowpack upstream means more runoff later in the season.
| SNOTEL station | Snowpack |
|---|---|
| Freehold-Marlboro | 0 in |
| Highstown 2w | 0 in |
| Exton | 0 in |
| 0.2 Mi E Of Harrison P.O. Passaic Rvr | 0 in |
| Flemington 5 Nnw | 0 in |
| Mendham 1.5 W | 0 in |
River levels & flood safety
- Read the level before you go
- A river that's runnable at one flow can be deadly at another. Check current discharge and gage height — like the values shown above — against the flood-stage thresholds, and remember levels can spike fast after rain or a dam release.
- Respect cold water
- Snowmelt rivers run cold even in summer. Sudden immersion triggers cold-water shock and saps strength within minutes. Wear a PFD, dress for the water temperature (not the air), and never wade or paddle alone.
- Watch for swiftwater hazards
- Strainers (downed trees), undercut rocks, and low-head dams are the deadliest features on moving water. High, fast, muddy water hides them. If in doubt, scout from shore and portage.
- Mind flash floods & releases
- Narrow canyons can flood from a storm miles upstream, and dam-controlled reaches can rise without warning. Know the forecast, the release schedule, and your exit before you launch.
Track Manalapan Brook At Spotswood in the Snoflo app
Save this gauge as a favorite, set push alerts when streamflow crosses a threshold (e.g. "alert me when Manalapan Brook At Spotswood crosses 5,000 cfs"), and Snoflo's iOS app will push the moment USGS reports the crossing.
About Manalapan Brook At Spotswood
Where does the streamflow data for Manalapan Brook At Spotswood come from?
Discharge, gage height, and water temperature come directly from the USGS streamflow gauge 01405400. Snoflo refreshes the time series throughout the day. Forecasts come from the NOAA / yr.no feed Snoflo's iOS app uses.
How often is the report updated?
USGS gauges report continuously (typically every 15 minutes). Snoflo pulls fresh values throughout the day — look for the "as of" timestamp on the streamflow hero card.
What's the difference between discharge and gage height?
Discharge (cubic feet per second, or cfs) is the volume of water flowing past the gauge each second. Gage height is how high the water sits at the gauge (feet). They're related by a rating curve specific to each gauge — higher water means more flow, but the exact ratio depends on channel shape.
How is "percent of median" calculated?
Today's discharge is compared to the historical median discharge on this calendar day across the gauge's full record. 100% = right on median; 200% = a very high year; 30% = a drought-level low.
What are flood stages, and is this river safe right now?
Flood stages are NWS-defined gage-height thresholds — Action, Minor, Moderate, Major — marking when nearby roads or floodplains start to be affected. "Safe" depends on your activity and skill: a level that's a fun paddle for an expert can be lethal for a wader. Always check the current level against the thresholds above and the safety links, and when in doubt, stay off the water.
Can I get alerts when Manalapan Brook At Spotswood rises?
Yes — flow alerts are managed in the Snoflo iOS app. Favorite this gauge, set a streamflow threshold (e.g. "alert me when discharge crosses 5,000 cfs"), and you'll get a push the moment USGS reports the crossing.
Access the free Manalapan Brook At Spotswood report
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