The North Bay-Mattawa Conservation Authority issues flood watch

 35 to 55mm of rain in the forecast, adding to the spring melt, has prompted the authority to advise residents.

A Flood watch notifies the potential for flooding exists within specific watercourses and municipalities. Municipalities, emergency services and individual landowners in flood-prone areas should prepare.

“We expect flooding in area streams and rivers due to the timing, duration and amount of rain expected during this weather event, together with several watershed conditions. We have above average water levels in watercourses and above average snow pack depth and water content which will melt more quickly with the rain and higher temperatures expected during this event,” said Kurtis Romanchuk, NBMCA’s Duty Officer.

A Colorado low combined with a Texas low is moving into the area, bringing the warmer temperatures and substantial precipitation. It is expected to move across northeastern Ontario tonight, continuing on Thursday and Friday, before leaving the province later in the weekend. Between 35mm and 55mm of rain is forecast over the weekend, with the majority forecasted for Wednesday night and early Thursday morning. Temperatures are expected to be in the 0-10°C range.

The snowpack held approximately 123mm of water as of the most recent survey on April 15 which is 425% of the long-term average for this time of year.

The gauges NBMCA monitors on Chippewa Creek, Wasi River, LaVase River, and Amable du Fond River show all are above average. Urban watercourses such as Chippewa Creek and Parks Creek and smaller watercourses will rise more quickly during this event. Lake Nipissing has been rising, but is not expected to flood at this time.

Lake Nipissing water levels are being monitored. As the snow and water content in the upper watershed release and make their way to the lakes, we may see some changes there in a few weeks’ time

“As this event seeps through the system, lake levels rise, and shift from frozen to flowing over the next week we should see the ice on the lakes rise and pose some challenges for shorelines. We’ll be monitoring the lake levels and advising the public as those conditions change,” said Romanchuk.

Ice conditions are already hazardous and conditions will become even more so wherever creeks or rivers enter lakes. With the increased flow, shorelines and banks will be slippery and the public should stay away from those areas.

All residents, especially those in low lying areas, are encouraged to monitor the conditions that are developing. Municipalities are encouraged to monitor water crossings to ensure the continual movement of water through culverts and bridges.