WHAT'S HAPPENING NOW
—— ft above typical
Finding the top signal on the water…
Live river level, flow, historical records and forecast for Lesser Slave River at Slave Lake in AB, Canada, built from official government gauge data.
The Lesser Slave River sits in the Lesser Slave watershed in Alberta.
This station drains 13,550 km2 (5,232 sq mi) upstream of the gauge. That is the area feeding the reading here, not the whole watershed by name.
For people watching the river near Slave Lake, the key pattern is the spread between the usual low and high months. The typical level is 576.09 m (1,890.07 ft) in March and 576.55 m (1,891.57 ft) in July. The typical annual swing is 45.8 cm (18 in), so docks, intakes, and shoreline access need to handle that much change over the year.
The record high is 577.81 m (1,895.7 ft) in July 2020. The record low is 575.57 m (1,888.34 ft) in November 2015. Those two marks show the range this gauge has seen over 38 years on record.
The seasonal shape is simple: the river is usually lower in March and higher in July. In this part of Alberta, that fits the broader rhythm of late-spring runoff and summer storm response, but the gauge record itself just shows the rise and fall.
No fastest 24-hour rise is listed in the facts here, so there is no warning-time figure to add from this station.
The hero number on this page is the current level set against the median for this calendar day across the station record. That comparison matters more than raw elevation because it shows whether today sits above or below the usual range for this date.
At this station, the reference comes from the Water Survey of Canada. With 38 years of record, that day-by-day median gives a clearer read than a single elevation does for anyone checking access, flow conditions, or bank response.
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.
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.
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.
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.
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.
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.
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.
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