Lesser Slave Lake Water Level
Live lake level, flow, historical records and forecast for Lesser Slave Lake in 75-10-W5, AB, Canada, built from official government gauge data.
- Location 75-10-W5, AB, Canada
- Watershed lesser slave lake
- Primary gauge 07BJ001 (Water Survey of Canada)
About Lesser Slave Lake
Lesser Slave Lake sits in Alberta.
Season by season
The lake’s usual high point comes in May, when the typical level is 584.3 m (1916.99 ft). The usual low point comes in September, at 583.05 m (1912.89 ft). That makes the typical annual swing 1.25 m (4.1 ft).
For people with docks, intakes, or shoreline gear, that swing is the part to plan around. May is the month to watch for higher water, while late summer into September is the time when levels are usually lower. In a foothills and prairie setting, that seasonal shape fits the broader rhythm of late-spring peaks and summer declines.
Records and rises
The record high here is 590.55 m (1937.51 ft) in June 2018. The record low is 582.68 m (1911.68 ft) in December 2023.
Those two numbers show the range this lake can reach across its record. The high-water mark is well above the usual seasonal peak, which matters for shoreline access and anything built close to the water. The low-water mark is below the usual September level, which matters for launching, drafting, and keeping shallow-water works in service.
This station has 111 years on record, so the page is working from a long local history.
Reading the hero number
The hero number on this page should be read against the median for this calendar day, not as a stand-alone elevation. That comparison tells you whether the lake is running above, below, or near its usual level for today.
Raw elevation by itself is less useful because the lake’s normal level changes through the year. A date-matched median puts today in context, which is what matters for cottagers, anglers, and anyone watching water supply or shoreline exposure.
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 17,900+ lakes and rivers
Real-time water levels, forecasts, and alerts for lakes and rivers in a growing number of countries. Built on official government data.
Nibi Metrics tracks more than 17,900 gauged lakes and rivers in a growing number of countries, reading directly from official federal monitoring networks: the Water Survey of Canada, the United States Geological Survey, Quebec's provincial hydrometric network, the Environment Agency for England, the Scottish Environment Protection Agency, Natural Resources Wales, the Office of Public Works in Ireland (waterlevel.ie), the Norwegian Water Resources and Energy Directorate (NVE), the State of Queensland's water monitoring network, and on the Great Lakes the Canadian Hydrographic Service and NOAA. 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.
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