Rural Water - Quarter 2, 2017 - 41
Town saves money by rehabilitating,
and not replacing, a tank
Raven Lining Systems
Town of Wilson, Oklahoma
The town of Wilson,
potable water is supplied from wells and
stored in four 80,000 gallon concrete
storage tanks that were built in the 1930s.
Two of these tanks were in extremely poor
condition, with cracks and leaks due to the
deterioration of the concrete exposing the
rebar. One of these tanks was leaking so
badly that it was taken out of commission,
which required the town to spend
$4,000 per month to purchase water to
meet their demand.
The town council needed to make a
quick decision on whether to replace these
clear well tanks, which would be very
expensive (more than $1 million) or find
a way to quickly fix them so they could
continue supplying safe, clean drinking
water for their town.
WT Energy Services evaluated this
challenge and recommended rehabilitating
these clear well tanks with Raven
AquataFlex® 510, which is a 100 percent
solids NSF ANSI61 pure polyurea lining for
The inside walls were covered with a
thick layer of Calcite (calcium carbonate) that
had built up over the last 80 years due to the
hard well water. This had to be removed,
along with any loose concrete, before the
rehabilitation process could begin.
Another challenge was the extreme cold
winter weather during the project, with
temperatures fluctuating between 20-50
degrees. This required a coating system that
was engineered to be both applied and cure
in a cold environment.
The applicator prepared the surface
by grit blasting to remove Calcite build up
and loose concrete. The walls were then
repaired using a cementitious material to
rebuild the extensive deterioration.
Due to the extreme weather conditions
during the project, the Raven 171FS was
recommended as the best primer for the
cold conditions to reduce out gassing.
The 171FS is a 100 percent solid, fastcuring concrete epoxy primer with little
to no blushing.
The final step was to apply an 80 to
100 mil top coat of the AquataFlex® 510.
As a quality control check to assure a
monolithic lining, WT Energy performed a
spark test on the structure and made any
The project was completed on time and
within budget. According to Buddy Way,
president of WT Energy, "The town of
Wilson needed to find a way to repair the
water tanks or build new ones. We were
able to provide a high quality, cost effective
engineered solution to provide a long-term
fix of the existing tanks for the town."
The cost of replacing the underground
water storage tanks would have been
around $1.4 million. "Thanks to tank
rehabilitation, the town of Wilson was able
to repair the tanks for $140,000, which
was a $1.26 million savings for the town,"
said Frank Schaaf, mayor of the town of
Wilson. On top of this capital savings, the
town will be able to realize an additional
$480,000 savings over the next 10 years
by not having to purchase as much water
from a neighboring town to meet the
town's potable water demand. ●