Ottawa River flooding has come in waves before

It's been a while, but this isn't the first time the Ottawa River has seen nearback-to-back floods.

As of Tuesday morning, the Ottawa River was flowing at a rate of 7,700 cubic metres per secondat the Carillon Dam, just downstream of Hawkesbury, Ont.

• Spring melt means worst flooding could yet be to come
• The latest flood-related road closures and detours
• Flooding in Pontiac to peak Saturday, officials say

It's flowed at that rateor higher in the Hawkesbury area only eight other times since 1900, according to data provided by the Ottawa River Regulation Secretariat:

• 2017: The highest flow recorded since 1900, at 9,100 cubic metres per second.
• 1976: 8,200 cubic metres per second.
• 1974: 8,100 cubic metres per second.
• 1951: 8,300 cubic metres per second (river flowprior to 1962 was measured elsewhere in the Hawkesbury area, as the Carillon Dam was not yet built).
• 1947: 8,175 cubic metres per second.
• 1928: 8,760 cubic metres per second.
• 1909: 8,400 cubic metres per second.

Similarly to this year and 2017, the river sawhigh flows in both1974 and 1976.

These high Ottawa Riverflows don't always result in the same flooding patterns, however. The flow out of the Gatineau River might beparticularly high one year, affecting nearby communities more than others.

"There are all kinds of variables that go into it. But in general, when it's that high, everybody'shaving trouble, everybody's seen flooding," saidOttawa River Regulation Secretariat senior regulation engineer Michael Sarich.

The toll of flooding in Pointe-Gatineau

5 years ago

Duration 1:19

Pat Fauteux says many of his relatives' homes have been demolished because of flood damage.