Watershed Conditions Statements
April 04, 2017
Flood Watch — Rain Bringing Spring High Waters
Rain presently falling is causing flows in the Rideau River to increase toward thresholds at which flooding can be expected to cause access issues to lower lying waterfront properties. The area first affected will be the Long Reach of the Rideau between Kars and Kemptville. In particular, access to Hilly Lane, Cedar Beach, Rideau Glen and other neighbourhoods on that reach of the river can be expected to be compromised as the rain enters the system today. Rain forecast in the order of fifty-five millimetres (mm) on Thursday and Friday can be expected to be followed by a peak on…
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Watershed Conditions Statements
Rain presently forecast for this week is expected to cause a significant increase in flows and water levels, potentially to 1:4 year frequency (flow that has a 25% probability of occurrence in any year). There is still some snow in the Rideau River watershed which will be much reduced today with the arrival of temperatures above 10 degrees. This will increase flows slowly through the day. Twenty millimetres of rain now forecast for Tuesday will cause further increases. Fifty millimetres of rain on Thursday and Friday can be expected to bring a peak on Saturday possibly in the range of…
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Watershed Conditions Statements
March 03, 2017
Deep Freeze Slows Runoff
Cold temperatures have slowed runoff and will cause declining water levels in watershed lakes and streams through the weekend. There is enough water moving through the system from the melt and rain that flows are still increasing in some tributaries. This will tail off today and levels can be expected to decline through the weekend. Weather forecasts indicate another warmup with some rain next week that could cause flows to increase again. The warm temperatures and increased flows caused the ice on all waterbodies to become unstable. With refreezing occurring, new ice will be forming. However, it will take a…
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Watershed Conditions Statements
February 27, 2017
Potential for Low-Lying Areas to be Flooded
Warm temperatures and rain could cause water levels to threaten access to lower lying communities. This message applies particularly to Hilly Lane, Cedar Beach and Rideau Glen and other small communities along the Long Reach of the Rideau River near Kemptville that are susceptible to flooding. The Hilly Lane community could start to have water encroaching on the access road by Wednesday as a result of above zero temperatures melting the remaining snow and a two-day total rainfall of as much as 20 millimetres. Fortunately, temperatures are forecast to fall below freezing by Wednesday night which can be expected to…
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Watershed Conditions Statements
February 17, 2017
Warming Trend Expected to Cause Unsafe Conditions
Daytime temperatures above freezing forecast for the weekend and into next week will cause melting and increased levels on watercourses throughout the Rideau River watershed. Above freezing temperatures will cause ice and snow melt over the next several days. There is sufficient snow on the ground in the lower part of the watershed to absorb most of the meltwater. However, areas to the south and west of the City of Ottawa, where there has been less snowfall, can be expected to have more runoff. In all cases, the ice cover can be expected to become unstable to various extents with…
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Watershed Conditions Statements
January 19, 2017
Drought Condition Downgraded to Minor
The drought status in the Rideau River watershed is being downgraded to “Minor” because the recent warm temperatures and precipitation have caused flows to increase significantly in watershed streams.Rain and snowmelt have caused flows in some streams to approach and, in some cases, exceed the long-term historical average flows. Kemptville Creek had low flows of .028 cubic metres per second (cms), 1.5% of average, in mid-October. Occasional thaws with rain since then have caused flows to increase in all streams and fluctuate around the average. Kemptville Creek flows have been consistently elevated since December 27 and reached three times the…
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Watershed Conditions Statements
