In Spring, when the incoming rivers run high, 
the release of excess water can be spectacular.
Up to a million gallons of water per second can pass
through this half-mile wide dam. 


The flow and function are remotely controlled
by computers where sensors monitor water levels
throughout the system of dams.

The rock walls are steep, needing agility to climb. 
This is our boat tied to the narrow centre island 
on the tranquil Quebec side of the outflow area.  
The fishfinder shows fish but no one fishes there.
Hydro has posted both sides of this rocky islet 
as hazardous, in case of sudden release of water
and the turbulence produced.







It's Our Fault!
This is the centre span of the Otto Holden dam.
Because the Ottawa River is the boundary
between two provinces, we can say the turbines
are out of view to the left on the Ontario side.
From a distance it is hard to believe this dam 
holds a wall of water 130 feet high and 31 miles long.
Remembering that the Ottawa River itself flows
along "a major fault line" that fact gave us pause
when magnitude 5.1 tremors were reported at Temiskaming.
Moose Rock and other sheer cliffs along its length
testify to the immense upheaval long ago.



Historic
Log Chute 
with Trees
A close view
of the structure 
has surprises.

Mountain ash 
and pin cherry
trees flourish
with their roots 
thrust into cracks 
in the concrete
of some of the
buttresses
of the dam.

We may cheer 
the Life Force 
even as we wonder
how much
their roots
weaken the dam.








Repairs in 1998


Built fifty years ago, the dam is showing its
age in leaks here and there along its length.
Above the rocks shown here on the Quebec side,
close to the dam, two freshwater ponds collect
leaks prior to their overflow into Holden Lake.


Slippery 
When Wet
Here 
at the foot 
of the dam 
over to the 
Quebec side,
there is an 
unofficial place
to tie a boat, 
perhaps 
to climb 
to the top
for a
much-improved
view.

Overflow 
from the ponds 
makes a little 
waterfall.







Workout Time
A partly cloudy day produced this dramatic view
of the Quebec shore with fall colours of birches.
Don't tell, or they may stop me, but it is also a
wonderful place to swim in black depth of water
within a meter of shore all the way (through these
next three pictures) to a point of land.  More
interesting by far than laps due to waterlevel
grottos in the igneous and metamorphic rock.







In the Swim of Things
There are no weeds to tangle legs in deepwater
swimming.  With no current on the Quebec half of
outflow, although posted as hazardous in case of
sudden release of water, being within one good
stroke of shore makes it a safe and wonderful swim.
I wish I had dared to swim here years ago!
If it became a popular spot for swimmers however,
there are safety considerations to remember.





 Out of the Bay

Several landing places make this shore good for
picnic stops, but Hydro did not intend it as such.
For swimming, in this photo, the black deep ends
suddenly in knee-deep round stones that extend 
in shallows at most points including this one.
Fishermen prefer the white water below the turbines, 
as do the gulls and cormorants.  Blue in the distance 
of this hazy day is a cliff locally called Moose Rock,
and five miles beyond it, the town of Mattawa.




 Turbulence

Looking south, and having left the calm of the bay
we find the turbulence they warn about.  With wind
this rough water becomes very choppy.  Eddies,
swirls, upsurges and undertows, all dangerously
shifting and unpredictable, are a favourite place
for loons and fishermen alike, with good catches
of walleye (pickerel) and bass.

ABOVE THE DAM





Eagle's View

This is the top of the dam as seen from the lift-
road while moving a boat to Lac la Cave more than
100 feet above Holden Lake.  Here the generating
station produces *more than a million megawatts
of power, and its hum carries far over the water.
You can see the rocky island which separates the
outflow and where a large number of gulls nest,
safe from predators. (*Thanks to Wilston Steer in
his book "Along the Moccasin Line.")





At the Ramp
The boat ramp, here shown with calm water, leaves
boats at the mercy of current and wind but the
staff is there to assist.  Barrier buoys warn of
undertows best avoided even with larger boats.





End of the Line
For a boat approaching from the north on a hazy
calm day, the low line of the dam can catch
speeding boaters unaware.  Worse is a strong north
wind that has built through the wind-tunnel of
tall cliffs to the north which makes the landing
quite tricky.  One boater I know had to leave
his pontoon boat on the safer wrong side of the
dock to wait for calmer weather before it could
safely be loaded onto the trailer for transport.
The staff provided transport into Mattawa
for the night, and later delivery to the boat.







Lac LACAVE
This is the view greeting boaters who proceed
north into Lac LaCave.  Vista after vista opens out
to beckon travellers to see what waits to be seen.  



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