Down
Under:
What’s it really like inside a sewer manhole?
yres Associates civil engineers Chris Pletcher
and Sam Lowe like to call what’s inside a sewer
manhole “organic stuff” – which they figure is a
lot better than calling it what it really is. But just because
they may use a euphemism to describe human waste
doesn’t mean they find the job of going inside manholes
unwelcome. In fact, they truly enjoy the work.
A
there is nothing combustible. “If there is no hazard, then
all we are dealing with is an offensive odor,” Pletcher said.
“I like the problem-solving aspect of it,” Lowe said,
describing the job of sewer flow monitoring. “We’re trying
to solve the mystery of where rain is getting into the
system, and we’re looking for clues.”
“Stagnant water is the worst,” Pletcher added. “Otherwise,
it kind of smells like coffee and cocoa.” He said it doesn’t
tend to stink except in the case of a pipe with a lot of silt
and muck. “When you disturb the silt, it stinks.”
For Ayres’ crew, safety is put first when working inside the
manholes. The group requires three people present for
each confined space entry: an attendant, an entrant, and a
supervisor. The attendant is always watching the entrant,
or person “in the hole.” The job requires specialized
training for confined space entry and first aid/CPR.
However, dealing with the smell may be an acquired taste.
“We’ve had first-timers who overthink the process, and
that can gag you,” Pletcher said.
“We make sure safety of our staff is paramount,” Pletcher
said. The group uses an air monitor for checking the
atmosphere inside the manhole for safe levels of hydrogen
sulfide, oxygen, and carbon monoxide, and making sure
But not that offensive, Lowe said. “In my opinion it’s a
somewhat sweet, moderate odor, but not necessarily rank
most of the time,” he said. “That’s because it’s moving
water, not stagnant.”
On a frigid day or a sweltering summer day, being in a
manhole isn’t so bad, Lowe said. “It’s climate-controlled
because it’s underground – it’s always 50 to 60 degrees. I
recall a day in Cheyenne it was bitterly cold out, but in the
manhole it was pleasant.”
— Tawny Quast
TRENDS
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