The self-supporting steel lattice towers, for which Roterra
is installing the foundations, have a smaller overall footprint
compared to guyed towers supported by cables. The
right-of-way width for the self-supporting towers is 80
metres; an added benefit to reduce the impact on farming
operations as the towers are being erected in cultivated and
agricultural areas.
One of the more unique aspects of this project has been
related to the uneven topography along the berm of the Red
River Floodway, where much of Roterra’s work has been
focused. The grade of the steep hills in this area can be
markedly different from one side of the tower foundation
to the other. In places where the tower legs are located on
the higher elevation side of the berm, Roterra often used a
three-pile foundation group per leg. Then, for the legs that
are on the lower side of the berm – which have a much
higher stick-up of approximately two metres – engineers
used five-pile groupings to account for the legs standing
significantly higher and not having the supporting earth
around them.
“These pile groups look really neat and are not something
we see very often,” said Laili Abolghasemi, project coordinator
at Roterra. “It’s been tremendously interesting to witness
how the design was accomplished in order to accommodate
the tower just for that specific project location.”
Manitoba experienced uncharacteristically wet weather
throughout the fall of 2019, seeing more than three times its
monthly precipitation average for September. For the first
time in the floodway’s history, the Province of Manitoba
opened the floodway during the fall to lower the threat of a
fall flood to Winnipeg. This created a number of challenges
for the project as the ground surrounding the floodway
became over-saturated with rainwater.
“Our initial planning for this project was to be able to
access everything with all of our equipment,” said Roterra
project manager, Kendall Fahey. “But when it rains without
any respite for a number of weeks, it means that a very large,
very beautiful, man-made berm that is composed of clay
becomes more than a little mucky to work on.”
Due to these wet conditions, for approximately three-anda
half weeks Roterra was only able to access the right-of-way
with tracked equipment and was unable to bring in its welding
or crew trucks. The company ended up using additional
skid steers to move gear into the project site and its project
client, Voltage Power, was able to secure Nodwell tracked carriers
to transport Roterra’s crew and welding equipment.
Then, as temperatures dropped in October, a heavy snowfall
over the Thanksgiving weekend would prove devastating
for power lines across the province, pulling Manitoba Hydro
resources away from the job to restore electricity to a number
of rural communities. Fortunately, Roterra’s piling crews
were on off days during this blizzard; although that was small
comfort since the hotel they were staying in lost power for
approximately 12 hours.
“Luckily Roterra vehicles all have power outlets, so we
could catch up on some administrative paperwork while
we watched the snow fall from the inside of the trucks,” said
Abolghasemi. “There were really just a couple days there
where we didn’t feel it would be safe to have our crews driving
but, by the following Sunday, we were back on site laying
the piles, cutting and setting out caps.”
Given the challenges that Roterra faced with the notoriously
inclement Manitoba weather last fall, the company’s
helical screw pile technology proved to be a distinct advantage
for use on MMTP as steel doesn’t care if the conditions
are wet or dry.
GREAT CANADIAN PROJECTS
Roterra’s five-pile groupings
on the lower side of the berm
46 Q1 2020 www.pilingcanada.ca
/www.pilingcanada.ca
