Applications & Innovations: Weathering Stormwater
Applications & Innovations
A tiny Arkansas town gets
ready for a flash flood
mall towns can face the same big problems as big towns
when it comes to stormwater infrastructure. This one
faced an essential emergency culvert repair without a lot
of reserve funding waiting at the bank.
They didn’t fund their way out it; they thought their way
out of it. Three days before a ﬂash ﬂood.
When a large sinkhole developed down the side of the main
thoroughfare in the town of Garner (pop.284), in central
Arkansas, some quick decisions had to be made, especially
when it was discovered that the drainage pipes installed more
than 30 years ago were completely rotted.
“You could see down about 3 feet into that sinkhole,”
Arnold Sewell, the mayor of Garner, Ark., tells Better Roads.
A patch was made over the two culverts where the hole
was on this south main highway, Sewell says. “But once we
got started, [we discovered] there was a bigger hole in the
side [of the pipes] than anticipated. The road has four culverts
about 50 yards apart. The second set of culverts, where the
water main is, has a concrete bridge over them. “These were
completely washed out inside,” Sewell says. In fact, the pipes
were so eroded they backed up water, always sending typical
drainage into the overﬂow culvert that was supposed to be
reserved for emergency stormwater.
The “usual” solution may not be the best
Completely replacing the pipes was going to be very difﬁcult
for the small community. The town could dig and replace the
pipes, but money wasn’t available. Plus, doing a complete
replacement would mean closing down the road. There are
a number of school buses that travel that road each day, and
closure would mean rerouting them 10 to 12 miles out of the
way, Sewell says.
A secondary road could be used, but 18 wheelers can’t use
But with an already-sinking roadbed, something needed to
be done, and done quickly. That’s when Sewell discovered an
alternate solution – simply relining the pipes.
30 June 2012 Better Roads
The culvert reline method cost-estimate was 40-percent less
than the cost of digging and replacing the pipe – based on
the initial quote. Overall, by relining the bad pipe instead of
digging it up and replacing it, this saved money and did not
have to shut down a main road. Sewell says it would have cost
$68,000 to dig out the pipes. “That is for demolition of the
culverts and replacing the galvanization,” Sewell says. “The
head bowl, which was about 4 feet tall and about 20 feet,
need to be replaced. Plus, if you add in the engineering feel, it
would have been around $75,000.”
Replacing only the liner pipe cost the cash-strapped town
about $46,000. When engineering fees are ﬁgured in, Sewell
says, the city saved about $27,000. “We’ve been asking for
donations,” he says. “You can ﬁll out for a grant, but it could
take a year. The road would be gone by then and it doesn’t do
you any good.”
The relining of the culverts was completed this spring.
Snap-Tite/ISCO Industries supplied the high-density polyethylene (HDPE) pipe liner, with Baldwin Construction serving
as the contractor on the project.
Just three days after the project was completed, ﬂash ﬂoods
slammed into Garner and its surrounding community. There
was tremendous rainfall, but in addition to local ﬂoodwater,