CORNWALL, Ontario - The warmer temperatures and rainfall in March may be a sign of better weather to come, but they also bring potentially dangerous conditions near rivers and streams, and the possibility of flooding.
Although the snow pack is melting slowly in the South Nation Watershed, Environment Canada is forecasting high temperatures and about 10 mm of rain throughout the watershed in the next couple of days.
In addition to daily and long-range weather forecasts from Environment Canada and the Ministry of Natural Resources, which provide anticipated temperatures and precipitation amounts, SNC has a number of monitoring programs that are key tools to determining the likelihood of flooding.
SNC monitors snow depth and its water equivalent at seven locations twice a month; this information indicates how well the snow will be able to absorb rainfall and excess water.
In addition, there is continuous monitoring of a total of ten stream gauges that measure river levels throughout the watershed. When monitoring indicates there is a heightened risk to public safety, a series of warning messages are issued.
A Watershed Conditions Statement is a notice of conditions that could be dangerous, like high flows or unsafe ice.
A Flood Watch is issued when there is potential for flooding, and a Flood Warning is issued when flooding is imminent and flood response plans should be activated.
During a flood event, SNC will continue to monitor the weather and water levels, and provide ongoing updates throughout the event. SNC also takes action to control water levels and reduce flooding through the operation of the Chesterville Dam.
“Water levels near an operated dam can change suddenly without warning,” says SNC Team Lead for Water Resources Sandra Mancini. “We caution residents – especially parents of young children – to be wary of changes in flows, high water levels and unstable ice.”
Flood forecasting and warning messages are distributed to all media in the watershed, and are posted on www.watershedconditions.com.