Underground Infrastructure - April 2023 - 13

a time without stopping, " Wright said.
" Then once it's done, we just load the pipe
into the boot and take off with the plow. "
The boot itself was custom-made for
RCWD. It threads the pipe over the cab
of the plow and down the center of the
windshield and hood, pushing it into an
opening in the boot and then into the
earth. It worked so well that in mid-2022,
RCWD invested in a higher-horsepower
plow that had been refabricated strictly
for pulling fused tiling (irrigation) pipe.
The results spoke for themselves. An
eight-inch, DR11 installation that Pick
thought would take several weeks was
completed in just two days.
" We actually caught up with the fusion
tech, who was ahead of us fusing the pipe
with a McElroy TracStar 412, " Pick said.
The process worked so efficiently that
Braun provided a second TracStar 412,
doubling the productivity and greatly
increasing the speed at which the water
lines could be installed. Braun provided
fusion training on the McElroy machinery
to System Operator Jared Swanson,
who received his fusion certification
shortly after.
" We chose the TracStar 412 because
its size range fit best with the pipes we
planned on using, " Wright said. " If we
need to increase our pipe size, we'll
definitely be looking at a larger McElroy
machine. "
Water sources
HDPE because of its availability, and
the fact that the product used by RWCD
is manufactured within the state. An
order for 13 miles of 8-inch HDPE, he
said, arrived in less than a month.
Aging water system
RCWD is one of South Dakota's oldest
water systems. Today, it's also one
of the largest systems in the state. But
its oldest lines are nearing the 50-year
mark, and a combination of increased
demand and pipe failures means the
district has been busy replacing the existing
lines with HDPE.
For pipe installation, RCWD uses the
plow-in method. More commonly seen
outside the United States, it involves
threading pre-fused pipe along or into the
furrow in a plow. A six-foot-deep pilot hole
is dug, then a boot attached to the plow is
guided into the pilot hole. As the plow,
pulled by a high-horsepower bulldozer,
digs the hole, the pipe threads through
the boot and goes into the ground.
The soil naturally falls back into the
trench, and a bulldozer following behind
the plow re-packs the soil, completing the
entire process. It's a method that's best
suited for long, open stretches of land -
much like the terrain around Lake Andes.
Plow-in is especially useful in farmland
because it can be used to install pipe
- such as irrigation lines or water lines
- with minimal soil disruption. It just so
happened that farmland made up a large
percentage of RCWD's sites.
" We can fuse five-mile stretches at
RCWD sources its water from the Francis
Kase Reservoir, located along the
Missouri River in the south-central part
of the state. This 5.7-million-acre lake
is the second-largest in the state, and
RCWD has three pumps that can provide
7,500 gallons per minute each.
As of winter 2022, RCWD was in the
process of expanding its pump capabilities,
installing 1,500 feet of 28-inch IPS
DR13.5 pipe to boost its capacity further.
Now, for Pick, the sky's the limit on
possibilities.
" The city of Mitchell, which is a community
of about 15,000 people, called
us wanting to install a redundant water
source, " Pick said. " We met with them to
discuss a project that would be roughly
70 miles of 20- to 24-inch HDPE. "
Pick wants RCWD to be an example
of how HDPE can change the industry.
" We're sold on HDPE, " he said. " We
UndergroundInfrastructure.com | APRIL 2023 13
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Underground Infrastructure - April 2023

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