By David Tucker EBS CONTRIBUTOR
As if we needed another reason to stop eating
bacon cheeseburgers, it turns out that greasy foods are clogging more than just
our arteries. According to the Big Sky Water and Sewer District, fats, oils and
greases, or FOGs, are also clogging Big Sky’s sewer system, leading to nasty
overflows and damaging vital infrastructure.
“We’ve all seen the fat that congeals in the
bacon pan,” said Grant Burroughs, wastewater superintendent for the Big Sky
Water and Sewer District. “Now multiply that by a million.” That’s a rough
“estimate” of the volume of FOGs flowing from town’s restaurants, bars and
hotels, and into the sewer system, but how are they getting there and how can
they be stopped?
As with many of the challenges facing the
community of Big Sky, the FOG issue has been exacerbated by rapid growth. “The
vast majority of the problem comes from commercial businesses,” Burroughs said.
“We have more restaurants cooking food with butter and grease.”
Most restaurants have a solution for
separating FOGs from other wastewater, but that solution only works if it’s
maintained. Grease traps, as they’re aptly named, are designed to filter out
the majority of the fatty residue that gets washed off dishes and down the
drain. Over time, grease builds up in the traps, but if they aren’t inspected
and maintained, the grease can overflow back into the main wastewater pipes. In
the pipes, the grease congeals, causing clogs that ultimately result in overflow.
“Last winter, a 10-inch sewer main got
clogged, causing a sewer overflow,” Burroughs said. “This is bad for the
environment and a real pain to clean. Blocked sewer mains can also back up into a house through the sewer
lateral, carrying waste from the house to the main.”
As more restaurants come online and the volume
of FOGs increases, the problem isn’t going to get any smaller. High
concentration areas like Town Center and the Meadow Village, where most of the
restaurants are, see the most FOG build up. “We clean these areas year after
year, and cleaning the sewer costs a lot of money and time,” Burroughs said.
Messy, damaging overflows are just the first
part of Big Sky’s FOG problem. When FOG-filled wastewater reaches the treatment
plant, another destructive process begins. Much like fat coats our arteries and
diminishes the function of our heart, FOGs can coat sensors, plug pumps and
generally diminish the function of treatment-plant infrastructure. Burroughs
said cleaning the equipment slows everything down and is expensive, and coated
sensors lead to misleading readings.
In addition to coating and clogging, FOGs also
promote filamentous bacteria, which prevents waste from settling in the
treatment process. “We’re not getting full treatment of wastewater,” Burroughs
said. This might be the biggest problem of all. If FOGs are impairing the
wastewater treatment plant’s functionality, that’s a major potential issue for
watershed health.
So, what’s the solution? As with many things,
education and outreach could go a long way.
“We need to change our
ordinances to better reflect the problems we see,” Burroughs said. “That will
help businesses handle this problem.” He suggested grease-collection sites
around Big Sky where grease-removal companies could repurpose oil for biofuel,
which seems like a great way to solve two problems at once, and a great
upcycling opportunity.
As for residential sewer systems, Burroughs
doesn’t see as big of a problem. “Typically, this is more of a commercial
thing. We don’t really see it in residential sewer-collection systems.” If you
do cook with a lot of oil or fat, avoid washing it straight down the drain.
Throw it out in the bottle or wait for grease to congeal, then wipe it from the
pan and throw it in the garbage.
David Tucker is the communications manager for the Gallatin River Task Force.