Ottawa River at Mattawa Water Level
Live river level, flow, historical records and forecast for Ottawa River at Mattawa in ON, Canada, built from official government gauge data.
- Location ON, Canada
- Watershed upper ottawa kipawa
- Primary gauge 02JE013 (Water Survey of Canada)
About Ottawa River at Mattawa
Ottawa River at Mattawa is a gauged river in the Upper Ottawa - Kipawa watershed, Ontario.
The watershed
This reach sits in the Upper Ottawa - Kipawa watershed in Ontario, with a long record behind it: more than 120 years. For people living, boating, or fishing here, that matters because the river’s range is not a guess; it is measured across a long span of seasons.
The seasonal pattern is straightforward. The highest typical month is May at 52.72 m (172.98 ft), and the lowest typical month is March at 51.63 m (169.4 ft). The typical annual swing is 1.09 m (3.6 ft). That is enough to change dock access, shoreline wetting, and how much clearance a shallow landing or intake has through the year.
The extremes are wider. The record high is 55.78 m (183 ft) in May 1960. The record low is 49.95 m (163.87 ft) in October 1914. Those two marks show the spread that a fixed installation has to live with over time, even when the usual year stays inside a much smaller band.
What the numbers say
The river’s peak month is May, which fits a snowmelt-driven rise in this region. The lowest typical month is March, before the spring lift arrives. After that, the water usually eases down through summer and into early winter.
For a dock owner, the key point is the size of the normal seasonal change: 1.09 m (3.6 ft). For anglers, that means the waterline and nearshore conditions can shift enough to alter where fish hold and where you can safely launch or land a boat. For anyone with a pump, intake, or shoreline structure, the record high and record low frame the long-term envelope, while the monthly typical levels show the more common operating range.
Reading the hero number
The hero number on this page is the best quick check for today’s stage because it compares today’s reading with the median for this calendar day in the station record. That is more useful than raw elevation alone: a level can look ordinary in one season and high or low in another.
With more than 120 years of record at this station, the comparison puts today’s water in context for this date, not just at this moment. That is the number to use when deciding whether the river is running close to its usual line, or standing above or below what Mattawa typically sees on this day.
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.
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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
