L Pontchartrain at Crossover 4 near Mandeville Water Level
Live lake level, flow, historical records and forecast for L Pontchartrain at Crossover 4 near Mandeville in LA, United States, built from official government gauge data.
- Location LA, United States
- Watershed lake pontchartrain
- Primary gauge 301200090072400 (USGS)
About L Pontchartrain at Crossover 4 near Mandeville
Lake Pontchartrain in Louisiana sits in the Lake Pontchartrain watershed.
What the record shows
The record on this station runs back more than 10 years of USGS data. The high point is 5.39 ft (1.64 m) in August 2021, and the low point is -1.76 ft (-0.53 m) in February 2026. That spread is part of what people see on docks, shorelines, and low-lying access points: water here can sit above or below the gauge zero and still move through a fairly narrow seasonal band.
The usual seasonal shape is not large, but it matters. October is the highest typical month at 1.11 ft (0.34 m), while January is the lowest typical month at -0.06 ft (-0.02 m). The typical annual swing is 14 in (35.6 cm). For anyone keeping an eye on a dock, ramp, or shoreline edge, that is the range the water tends to work within before weather pushes it outside the norm.
In this part of the Gulf lowlands, slow drainage means water can stay up for days after rain or surge. That is the regional rhythm to watch: a rise can linger, and a high stage can outlast the storm that started it.
The watershed
This station is on Lake Pontchartrain, and the drainage area above the station is not given here, so there is nothing to add on catchment size.
For people around the lake, the useful part is timing. The lake’s record shows a modest seasonal swing, but the extremes are much wider than the usual month-to-month change. That is the difference between ordinary water levels and the kind of water that changes access, floods low ground, or keeps a shoreline wet longer than expected.
Reading the hero number
The hero number on this page is best read against the median for this calendar day, not as a raw elevation. A stage on one date can be ordinary here and unusual on another, so the calendar-day median gives the clearer comparison.
This station is a USGS site with more than 10 years on record. When the hero number sits above the median, it means the lake is running higher than is typical for this day in the record; when it sits below, it is running lower than typical. That makes the number more useful than elevation alone for anyone checking whether conditions are normal for the date.
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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How every number is computed - About the platform
