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Rideau River in Ontario

River33.9 mi
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Around here

Around Rideau River

Arklan Rapids21.3 mi5 mi

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Source: Canadian Geographical Names Database (NRCan), Open Government Licence - Canada · Public land: USGS PAD-US

About this river

Rideau River is a 33.9 mile river. Streamflow is measured at the Water Survey of Canada gauge Rideau River below Merrickville (site 02LA011). Reach geometry comes from Natural Resources Canada's National Hydro Network.

Typical flow by month

1979 to 2025

Rideau River typically runs highest in April, at a median 1,896 cfs, and lowest in September, at 265 cfs. The highest flow on record for any single day is 5,333 cfs, in 1993.

Show the numbers
Typical flow by month at Rideau River below Merrickville, in cfs
MonthTypical (cfs)Usual range (cfs)
January690429 to 1,036
February638465 to 916
March1,014698 to 1,518
April1,8961,289 to 2,479
May770415 to 1,232
June390268 to 562
July298239 to 366
August279247 to 353
September265235 to 373
October461300 to 622
November596285 to 840
December660360 to 1,243

Typical is the median of each month’s daily median values, and the usual range runs from the median 25th to the median 75th percentile, across about 20 years of record. Statistics published by the US Geological Survey for Rideau River below Merrickville (site 02LA011). Conditions on any given day can fall well outside the usual range. Check the current reading before you go.

Made to print

Put Rideau River on your wall

This river section as an art print, drawn over the real terrain with its miles, plus the trails, roads and peaks around it. Pick the colors and the size, and see the finished print before you buy. From $39, shipping included.

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Paste this snippet anywhere, an outfitter page, a club site, a trip report, to show Rideau River's live streamflow, water level and 7-day trend. It reads the USGS gauge directly, updates itself, and links back here.

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