Modification of the crest of the falls
to spread the flow over the width
of the main flow channel
(approximately 8 m wide) was the
preferred option identified in the
environmental assessment report.
However, as the river corridor was
being regulated as a ‘Natural
Environment’ addition to White Lake
Provincial Park, it was subsequently
agreed that any potential for crest
modification would be assessed
after the project was constructed
and operational.
This option would involve filling the depression on the
left side of the falls (as viewed from downstream –
see location of water flow in base case situation
photo) with reinforced concrete or other suitable
material such that flow is distributed more evenly
across the entire width of the falls crest. Measures
would be taken to ensure that turbulence and a
natural appearance are maintained (i.e. embed
boulders and/or shaped surfaces to mimic existing
crest characteristics). The graphical representations
on the right show the anticipated view at 1, 3 and
6 m3/s with a modified crest.
While the implementation of this option would incur an additional capital expense that
would be added to project debt, it could also increase the project revenues for the
1 m3/s and 3 m3/s flows in the same manner as noted for the previously described “Less Flow” option. The 6 m3/s option would maintain the status quo in terms of benefits
to the Ojibways of the Pic River First Nation (see “Base Case Situation”), while providing
a more scenic viewing experience.
It should be noted that during periods of low flow, the amount of flow that could be
released over the falls is limited to the actual flow in the river.
Variable Flow Timing Options
The variable flow timing option
would vary the flow over the falls
between active viewing and
non-viewing periods.
For example, activation of a
remote sensor would increase the
flow over the falls during visitation
periods (by reducing the flow
through the facility), while flow would
be lower at other times when no
one is viewing the falls. Alternately, a manually
operated device could be located at the powerhouse
to allow visitors to increase the flow when they are
on-site and ready to visit the falls.
The option would provide for a more scenic
experience, as higher flows could be attained during
the short intervals that visitors are present, as
compared to the constant flow presently provided
during daylight hours from May 15 to September
15 annually. The photos on the right illustrate the
base case situation as well as the scenic experience
that could be attained with this option. The 12 and
24 m3/s options are based on average viewing
periods of 2 hours per day during the months of
July and August, and 1 hour per day during the months
of May, June and September. This results in a total of
184 hours, which corresponds to approximately the long term average number
of visitors to the site per year
It should be noted that during periods of low flow, the amount of flow that could be
released over the falls is limited to the actual flow in the river.
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