St. Marys River near Garden River Water Level
Live river level, flow, historical records and forecast for St. Marys River near Garden River in ON, Canada, built from official government gauge data.
- Location ON, Canada
- Watershed garden
- Primary gauge 02CA003 (Water Survey of Canada)
About St. Marys River near Garden River
St. Marys River near Garden River is a gauged river in the Garden watershed, Ontario.
The watershed
The station drains 229000 km2 (88417 sq mi) upstream of this point. That is the area feeding the gauge, not the whole watershed label on the page.
The river’s seasonal pattern fits a snowmelt-driven system. Spring freshet comes in late April-May, then the level usually eases back through July-September, with an early-winter decline as ice forms.
What the numbers say
The highest recorded level is 25.18 m (82.6 ft), set in October 1986. The lowest recorded level is 23.09 m (75.76 ft), set in October 2012.
The typical seasonal high is in July at 24.31 m (79.77 ft), and the typical seasonal low is in December at 24.14 m (79.21 ft). That annual swing is 17 cm (6.7 in), so day-to-day changes are usually small compared with the full range on record.
For a dock, intake, or shoreline setup, the record range matters more than a single reading. The difference between the record high and record low is enough to change edge conditions, but the normal seasonal swing is much tighter.
Reading the hero number
The hero number on this page is today’s reading set against the median for this calendar day across more than 53 years of record. That comparison is more useful than raw elevation alone because it shows whether the river is running near its usual level for this date, not just where it sits relative to a fixed datum.
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
Field notes and explainers from the Nibi desk - how to read a staff gauge, what a 100-year flood actually means, how snowpack becomes summer water.
For five years, spring 2019 was the mark every Lake Muskoka decision answered to. In April 2026 the lake went two centimeters higher - and the official books have not caught up yet.
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
