North Branch Raritan River at South Branch NJ Water Level
Live river level, flow, historical records and forecast for North Branch Raritan River at South Branch NJ in NJ, United States, built from official government gauge data.
- Location NJ, United States
- Watershed raritan
- Primary gauge 01400010 (USGS)
About North Branch Raritan River at South Branch NJ
North Branch Raritan River at South Branch NJ is a gauged river in the Raritan watershed, New Jersey.
What the record shows
This station has more than 18 years of record, enough to show a reach that can move from ordinary stage to a sharp spike. The record high is 16.72 ft (5.1 m), set in September 2021. The record low is 1.33 ft (0.41 m), set in January 2026.
That spread matters for people using the river nearby. A dock, crossing, or intake built for the day-to-day level still has to tolerate a much wider envelope when the river gets pushed by a wet spell or a storm remnant. In this part of the Mid-Atlantic, winter and spring rain floods are part of the pattern, and the biggest events often come with tropical systems or their remnants.
The seasonal pattern is narrower than the full record, but it still shows a useful rhythm. March is the highest typical month at 2.29 ft (0.7 m), while October is the lowest typical month at 1.65 ft (0.5 m). The typical annual swing is 7.8 in (19.7 cm). That is the change a regular user will feel most often from month to month, even when the river stays well inside its extremes.
The watershed
The gauge drains 190 sq mi (492 km2) upstream of the station. That is the land area feeding this reading, not the whole Raritan basin. For neighbours and anglers, that means rain anywhere in that upstream catchment can show up here in the stage.
Because the watershed is not huge, the river can respond quickly when widespread rain falls across it. In summer, lower flows are the norm across the region, so late-season water use, bank access, and fish habitat are often governed by how low the channel runs for that month rather than by the annual high-water mark.
Reading the hero number
The hero number on the page is the current level set against the median for this calendar day in the station’s own record. That is more useful than raw elevation alone because it shows whether today is typical for this date, high for the season, or low for the season.
At this station, the comparison is backed by more than 18 years of USGS record. That longer history is what lets the page place today’s reading in context for this river, instead of treating every stage value as if it meant the same thing in every month.
How this page is built
Readings come from official government gauges and are rolled into daily records: the daily mean, high and low for every day on record. Each calendar day gets its own baseline from the full history, so the level you see is compared against what this specific date usually looks like rather than an annual average.
How Nibi Metrics works · Water stories
Nibi Metrics - live water levels, flow, and forecasts for lakes and rivers across Canada, the US and the UK
Real-time water levels, forecasts, and alerts for lakes and rivers across Canada, the US and the UK. Built on official government data.
Nibi Metrics tracks more than 13,000 gauged lakes and rivers across Canada, the United States and the United Kingdom, reading directly from official federal monitoring networks: the Water Survey of Canada, the United States Geological Survey, Quebec's provincial hydrometric network, and the Environment Agency for England. Every number on the platform is measured, not modelled - taken from a government gauge on the water itself and compared against that location's own historical record for this exact date.
What you can see for any monitored lake or river
The level right now, in feet or metres, updated as the source agency publishes new readings - for many stations that is every five to fifteen minutes. How today compares to typical: every location carries its own typical-for-this-date band built from its historical record, so a reading is never just a number - it is above, below, or near what this water usually does on this calendar day. Which way it is moving: a measured RISING, FALLING, or STEADY verdict computed from the gauge's own recent readings, with the rate of change - the difference between a flood ending and one beginning. What comes next: level forecasts up to 72 hours ahead, driven by the gauge's recent behaviour, upstream water, and quantitative precipitation forecasts, alongside live radar, lightning, and weather for the surrounding region.
Alerts that watch the water for you
Set a threshold on any location - a level, a distance above typical, or a rate of climb - and Nibi emails or notifies you the moment the gauge crosses it. Cottagers use it for spring freshet, anglers for river conditions, marinas and municipalities for operations. The scanning runs around the clock against the same measured data shown on every page.
Where Nibi comes from
Nibi means water in Anishinaabemowin. The platform began at a family cottage on Lake Muskoka, Ontario, where the spring melt floods the shoreline most years and the only forecast was standing on the dock, looking, and guessing. It grew into an independent, member-funded platform run by Muskoka Research Inc. - no investors, no data resale, and a privacy policy shorter than most cookie banners. The core data is free for everyone, forever; paid plans add automation like multi-location alerts, deep history, and reports.
Coverage
Nibi spans the continent: every Canadian province and territory with active federal gauges - from Vancouver Island rivers to the Muskoka lakes, prairie reservoirs, and Quebec's hydrometric network - and the United States from Maine to the Texas Hill Country, the Ohio Valley, and the Pacific Northwest. Coverage grows where the water news is: when a basin floods, its gauges join the platform with their full historical records attached. Many stations report every five to fifteen minutes; most report at least hourly; every page states exactly when its gauge last spoke.
Free forever, funded by members
The core promise is simple: the water data is free, for everyone, forever. Live levels, maps, radar, and recent history never sit behind a paywall. Paid plans fund the platform by adding automation - multi-location alerts, decades of history, longer forecasts, and PDF reports - so the people who need more carry the cost for everyone who just needs to check the lake before driving up. There are no investors and no advertising deals shaping what the data says.
Water Stories
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Inside the freshet cycle that puts Manitoba shorelines at risk each year - and why 2026 broke the script.
The science of snow water equivalent and why it drives the season ahead.
What the numbers on the measuring stick actually tell you.
Why Central and South Texas rivers go from gravel beds to fifty-year records in an afternoon - including July 2026 on the Nueces.
One percent, every year, forever - unwrapping hydrology's most misunderstood phrase, and how it differs from our own percentiles.
How every number is computed - About the platform
