/Drawdown evaporation has levels on some lakes low

Drawdown evaporation has levels on some lakes low

Drawdown, evaporation has levels on some lakes low


By Chad Ingram

ongoing drawdown of lakes that are part of the Trent Severn Waterway
feeder system, combined with evaporation, mean water levels on a number
of county lakes are below average seasonal levels.
July’s hot, dry
weather has contributed to lower-than-usual levels in some areas of the
county. As a water management update from the TSW explains, rainfall for
July was 75 per cent below normal, and a similar trend is expected for
“The ongoing hot and dry conditions for the extended period
of time have resulted in lower than normal local inflows and enhanced
the rates of evaporation and the system transitioned from a normal
summer condition at the beginning of July to below normal conditions by
late July and early August,” the update reads. “Water management and
operational activities are conducted to appropriately respond to the
changes and may result in water level and fluctuations across the
While there was 10 to 15 mm of rain forecast last week, that
precipitation came mostly in the form of thunderstorms, meaning it was
sporadic and highly variable from one location to another.
According to the TSW, in Haliburton County, most lakes are near or below long-term average water levels.
“Levels continue to decline at a steady rate due to the active drawdown and enhanced lake evaporation rates,” the update reads.
of last week, the Gull River reservoir was 78 per cent full, the Burnt
River reservoir was 76 per cent full, and flows on both rivers were
slightly below average for the time of year.
A drawdown that began
Aug. 6 is scheduled to end Aug. 20, with levels dropping between 0.005
and nearly 0.4 metres depending on the lake. Some of the largest
scheduled drawdowns for lakes in the Gull River watershed included Percy
Lake at 0.398 metres; Horseshoe Lake at 0.37 metres; Sherborne Lake at
0.333 metres; Hawk Lake at 0.329 metres; and Twelve Mile Lake at 0.323
Drawdown forecasts can be found on the Parks Canada website at https://www.pc.gc.ca/en/lhn-