The rain event on Monday May 1 has caused water levels in the Rideau watershed to rise again.
Water levels in the Rideau Valley had fallen close to historical average levels since the spring freshet peak on April 7. As much as 60 millimetres of rain on Monday has caused levels to increase again. Another 70 millimetres is forecast to start Thursday and continue through the weekend which can be expected to cause a further rise of water levels.
Low-lying communities along the Long Reach of the Rideau between Kars and Kemptville can expect to see out of bank levels and it is possible that access roads could be over-topped. However, adjustments at the various dams on the system are being done to counter the rise. As the adjustments are made, residents can expect to see fluctuations in levels as the rain runoff passes through the watershed.
A factor in how high levels go in the Long Reach and downstream is the timing and volume of releases from the Rideau Canal reservoir lakes. Bobs Lake has remained high since the spring freshet. The other lakes, Wolfe, Upper Rideau and Big Rideau, have all gone above their respective Full Supply levels due to the rain yesterday. Full supply is the threshold at which damages can begin to occur.
Attempting to drive or walk in flowing water more than 30 centimetres deep is not advised. Parents need to inform children about the dangers of going near flooded areas and fast moving water in streams and ditches.
Conservation Authority staff will continue to monitor conditions and will issue updates as warranted.