Flood Warning Update for April 19, 2018

Please be advised that Otonabee Conservation has updated the FLOOD WARNING  issued for all watercourses / waterbodies in the Otonabee Region watershed.

This is an update to the FLOOD WARNING that was first issued Saturday April 14. A FLOOD WARNING is issued when flooding is imminent or occurring (for details, see text below).


In both the Kawartha Lakes and Haliburton Lakes regions there is currently no significant precipitation in the 7-day weather forecast. Over the following days, air temperatures in these two regions are expected to change from below-seasonal to seasonal to above-seasonable. Come Sunday/ Monday, it is expected air temperatures will be positive during both day and night with double-digit highs.


Recent measurements revealed that snow depths across the watershed varied between 9 and 15 centimeters, and the “snow water equivalent” ranged from 40 to 60 millimeters – theoretically, the snow water equivalent is the depth of water that would be released if the entire snowpack melted simultaneously. Also, the ground is saturated. With a few more days of single-digit above-zero daytime and below-zero nighttime air temperatures, the snowpack will slowly reduce. However, starting Sunday, when seasonal to above-seasonal air temperatures arrive to the area, whatever snowpack is still stored on the ground is expected to convert to liquid run-off (i.e., melt). Currently, there is significant pooling / ponding in low lying areas where there is poor drainage. This is expected to worsen in the coming days.  In addition, the water levels / flows in local rivers, streams and creeks that are currently well-above normal will increase. In addition, current minor / nuisance flooding will worsen beginning next Sunday when the melt is expected to arrive and area watercourses / waterbodies are expected to receive a pulse of increased meltwater run-off.


The snow water equivalent in the 4,367 square kilometer drainage area of the Haliburton Lakes region was recently measured to range from 40 to 90 millimeters. Current colder than normal air temperatures in the Haliburton Lakes region is holding that snowpack intact, which means that inflows to the Kawartha Lakes from the north are currently stable. Likewise, flows on the Otonabee River below Lock#19 are currently holding steady at an estimated 325 cubic meters per second. However, 24-hour positive air temperatures, and double-digit highs, starting Sunday / Monday, will cause rapid melting, thereby bringing alive the watercourses that flow from the north into the Kawartha Lakes. As a result, the Kawartha Lakes will rise, and outflows from the Kawartha Lakes, through the Otonabee River, will also increase, which in turn, will increase Rice Lake water levels.

Throughout the coming days, Otonabee Conservation will continue its monitoring of current conditions and forecasts.

This FLOOD WARNING will next be updated no later than 3:00 pm TUESDAY, APRIL 24, 2018.