Report to: LWCB meeting of January 12, 2016
Report by: Alan Roberts, P.Eng. – Director – Whiteshell Cottagers Association; and
Chair: Lake Water Levels Committee
Efforts to conduct the Winter Drawdown were thwarted by a heavy rainfall event in mid-November,
raising the water levels in virtually all of the lakes in the Whiteshell back to near summer normal levels.
We now have a potentially serious flooding situation that would result from severe cold together with a
near normal winter snowfall accumulation. The mild winter so far means the lakes are still draining,
which may alleviate a spring runoff accumulation problem.
Water level conditions have changed little since the beginning of December. Significant features
– The flow rate in the Whiteshell River at the discharge of Jessica Lake has come down to 150
cfs as of January 1, 2016 – near double the late summer normal; and Nutimik Lake is about
1 m (3.28 ft.) above the normal summer level.
– The elevation of West Hawk Lake (the headwaters of the Whiteshell River) is at 1091.6 ft. –
very near the middle of the normal summer operating range – close to where it was in the
fall of 2013. Protracted runoff from tributary lakes has prevented the rapid draw down of
West Hawk. Caddy Lake at 1044.5 ft. is 0.5 ft. above its winter drawdown elevation due
largely to discharge from West Hawk. Both lakes continue to drain with the mild
temperatures we’ve enjoyed thus far.
– Falcon Lake at 1066.0 ft. is one foot above its winter draw down elevation, with the Falcon
River at near the same elevation. The flow impediments in the Falcon River leave the lake
vulnerable to precipitation events of virtually any significance, and unlikely to achieve its
winter draw down level. Normal snowfall accumulation is likely to result in flooding
conditions again in the spring of 2016.
It appears that S. St. George’s observations of rising late summer and fall precipitation levels are valid.