Whitesail Lake Map-Area

West of the main divide, drainage is by trunk streams in deeply incised
valleys of the Kimsquit, Kitlope, and Kemano Rivers. These trunk streams
are fed by countless mountain torrents cascading from the high peaks, down
steep-sided mountains, through narrow ravines and canyons, to the floors of
these deep valleys.

The series of long, narrow, subparallel lakes along the eastern slope
of the Coast Mountains is the most striking drainage feature of the area.
Large lakes occur elsewhere along the eastern slope of these mountains but
nowhere are they as numerous as in Whitesail Lake map-area. Altogether
there are eight valleys that form major lake basins, all of which flow eastward.
The elevation of the lakes in these valleys varies from 2,614 to 3,100 feet.
As Upper Cretaceous and Tertiary rocks were deposited in these valleys it
seems most probable they originated in Cretaceous time. During Pleistocene
time these valleys formed avenues of egress for the ice flowing off the core
of the Coast Mountains. These ice streams excavated most deeply near the
mountains, thus forming the lake basins as we know them today. Post-
Pleistocene uplift has been recorded along the deep fiords but any such
uplift in this area has not been sufficient to erase the lake basins. One
important factor in their preservation is that no westward-flowing stream
on the opposite side of the mountains has eroded headward sufficiently to
capture any of the drainage feeding these lakes. If, for instance, a tributary
of Gamsby River had eroded headward sufficiently to capture Whitesail Lake,
possibly both Whitesail and Eutsuk Lakes would now drain westward.

Aluminum Company of Canada Power Development

The power development of the Aluminum Company of Canada has
changed the flow of the large lakes in this area from east to west and made
available over 1,600,000 horsepower. ‘This has been a great step forward
for British Columbia and for this part of the province in particular. The
roads built during construction give access to parts of the area hitherto
isolated and the growth of the city of Kitimat will bring many people into
the general region.

As early as 1930 and 1931 the Water Rights Branch of the Province
of British Columbia had information indicating that the lakes draining
eastward through the Nechako River could be made to flow westward
by damming the eastward flow and cutting a tunnel through the mountains
to the coast. Two alternative diversions were considered each of which
would develop only part of the lake system. One from Eutsuk Lake to
Kimsquit River was calculated to give upwards of 600,000 horsepower, and
one from Tahtsa Lake to Kemano River was calculated to give upwards of

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