Grand Bayou Reservoir at spillway near Coushatta Water Level
Live lake level, flow, historical records and forecast for Grand Bayou Reservoir at spillway near Coushatta in LA, United States, built from official government gauge data.
- Location LA, United States
- Watershed black lake bayou
- Primary gauge 07352820 (USGS)
About Grand Bayou Reservoir at spillway near Coushatta
Grand Bayou Reservoir sits in the Black Lake Bayou watershed in Louisiana.
Season by season
The seasonal range here is narrow. March is the highest typical month at 45.28 ft (13.8 m), while October is the lowest typical month at 44.42 ft (13.54 m). That typical annual swing is 10.4 in (26.4 cm), so docks, pumps, and shallow-water access see a modest change through the year rather than a wide seasonal shift.
For people using the reservoir, that means the day-to-day waterline usually stays close to its seasonal norm. March is the time to watch for the higher end of the yearly pattern, while October tends to sit near the lower end.
Records and rises
The record high is 50.95 ft (15.53 m), reached in March 2016. The record low is 38.06 ft (11.6 m), reached in December 2020. Those two marks show that the reservoir can sit far above or below its seasonal average in some years, even though the typical swing is small.
A fastest 24-hour rise is not listed in the facts, so there is nothing numeric here to use as warning time. In this part of Louisiana, slow drainage, backwater, and rainfall flooding can keep water elevated for days, so the broader pattern matters even when a single-day change is unavailable.
Reading the hero number
This USGS station has more than 13 years on record, so the hero number on the page should be read against the median for the same calendar day, not against the raw elevation alone. That comparison tells you whether today is typical for this date, higher than usual, or lower than usual for Grand Bayou Reservoir.
For a cottager, angler, or flood watcher, that is the useful number: it puts today’s stage in context with the station’s own record and seasonal pattern.
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
