Watershed Conditions Statements

The drought status in the Rideau River watershed that was left at “Minor” after a dry year in 2016 is, by this statement, reduced to “Normal”. The uncertainty that prompted holding the Minor status through the winter was because it wasn’t clear what state groundwater resources had been left at as the onset of winter arrived. With a period of warmer temperatures and the loss of much of the snow cover by late March, there was an opportunity to access the monitoring wells in the Rideau River watershed. Measurements indicated that groundwater levels had been restored to about the long…
As water levels and flows in the Rideau River watershed recede, levels on the Ottawa River have been rising. Rain on Saturday and Sunday had little impact on stream flows anywhere in the Rideau watershed. Rain forecast for Wednesday and Thursday of about 30 millimetres can be expected to cause flows to rise by as much as 50 cubic metres per second on the Rideau. This will not be enough to bring on the return of flooding in those areas recently affected. Levels on three of the four Rideau Canal reservoir lakes have been declining very slowly but are sensitive…
With access ways to the waterfront properties on the Long Reach of the Rideau River (Kars to Burritts Rapids) again passable, the Flood Warning, in place for the last week, is now reduced to Flood Watch.  Rain forecast for Saturday evening into Sunday is expected to cause an upturn in flows in the Rideau system. However, flows are expected to have receded sufficiently by then that the increase will have a minor impact. The expectation is that flows, as measured at the recording station at Carleton University, will increase to about 280 cubic metres per second (cms) by early Monday.…
Water levels have been dropping throughout the Rideau watershed since Saturday but not all flooded areas are fully dry yet. Water levels have dropped about 22 centimetres since the Saturday peak on the Long Reach between Burritts Rapids and Manotick. Another 34 centimetres are left to go on Hilly Lane and similar amounts on the neighbouring waterfront communities near Kemptville. Until those communities have safe access restored, the Flood Warning will remain in effect. The decline in levels in the Long Reach will be slowed by rain forecast for tomorrow and by water that has to be released from Big…
Runoff from the rain event on Thursday is working its way through the system leaving several waterfront communities still without access to their properties. Water levels have been holding more or less steady for the last few hours. A definite peak has not yet been reached but can be expected today. Cooler temperatures overnight have slowed the runoff process. Temperatures of over 10 degrees forecast for today will cause much of the remaining snow and ice to melt and run off today which will keep levels up for the short term. Once a definite decline of levels begins, Parks Canada…
Heavy rain on Thursday has caused streamflows and lake levels to increase significantly in the Rideau River watershed. The amount of rain that fell in eastern Ontario wasn’t quite as much as forecast but it is certainly having an impact. Such water levels were last reached in 2014. The worst impact is in North Grenville and rural Ottawa near the confluence of Kemptville Creek with the Rideau River. Some street and pathway flooding is occurring in Ottawa South adjacent to and in Windsor Park and in Ottawa East in Brantwood Park. No residential flooding in urban Ottawa has been reported…
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…
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…
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…
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…
 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…
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…
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…
The drought status in the Rideau River watershed is being downgraded to “Moderate” because recent precipitation has generally increased flows in area streams.  Kemptville Creek flows are about 130% of the historical average, or normal, for the time of year as a result of October rain and November snowmelt. Other recorded streamflows are above 60% of normal which has led to the downgrade of the drought status. However, the Tay River out of Bobs Lake has not had the same precipitation and is at only 10% of the normal flow. This indicates that the drought is not fully over despite…
The drought status in the Rideau River watershed remains at “Severe” because sustained flows in the streams and rivers have not been restored. As has been the case all summer, rainfall has been very erratic with significant amounts recorded at some monitoring stations and very little at others. There has been enough rain in the last two weeks to make many watershed residents forget that there is still a drought. Lawns are green. Farm crops are close to being ready for harvest.
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Contact Us

Address:
Rideau Valley Conservation Authority
3889 Rideau Valley Drive
Manotick, Ontario K4M 1A5

Phone:
613-692-3571, 1-800-267-3504

Email:
info@rvca.ca

Hours:
Monday to Friday, 8:30 a.m. to 4:30 p.m.

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