By Myrna Trauntvein
Times-News Correspondent
All along Interstate 15 in Utah the
population has exploded.
Mona is not escaping that explosion
with an average of 40 new building permits per year in 2006
and more than that expected in 2007.
Ed McCauley, section manager for
the Utah Division of Water Quality Engineering Section, said
his office manages the state revolving fund for sewer system
development in rural communities.
The idea that a certain population
number was the magic button for development of a sewer
system was not accurate, he said.
"A septic system (like those used
by Mona property owners) is not always the best solution for
wastewater disposal because each system is not always
well-maintained," said McCauley.
When the population of a rural area
is low it doesn't matter whether there is a sewer system or
not, but as the population grows, it begins to matter more
and more.
It would be less expensive, said
McCauley, if the sewer system were built in Mona soon. The
longer it takes to build such a system the more expensive it
becomes because of continued escalating construction costs
and because of the cost of tearing up more and more
streets.
First of all, the larger the number
of subdivisions are approved, the more streets there are.
Those streets, because of the subdivision ordinance, must
have asphalt surfaces. Those surfaces will need to be cut in
order to sewer lines to be installed. The more streets are
cut, the more expensive the installation becomes.
"In 2000, Mona was the 11th largest
city in the state at 850 residents that was not sewered,"
said McCauley.
Since that time, Mona has grown to
approximately 1,100 residents.
The community of Willard, said
McCauley, approached the DWQ several years ago, in 1994,
seeking to build a city wastewater system. However, the city
council then turned down the proposal and determined not to
build at that time. Recently, the city voted unanimously to
build the system. The price, in those few years, had more
than doubled.
As for a population quota, he said,
such ideas were not correct. Areas with culinary water and
sewer systems can support higher population density.
Nevertheless, small communities had constructed sewer
systems.
He said the state did not mandate a
sewer system. Still, it was a good plan to construct such a
system. It would bring tax dollars to the
community.
Those attracted to a community
wanted good schools and good services, a sewer system among
them.
"We have communities who have sewer
systems for less than 400 homes and one has under 100
homes," said McCauley.
He did say that the bigger the
community the more it costs to build a system.
It is possible to obtain a planning
advance, he said. The money would be used to study the
feasibility of a sewer system and would offer alternatives
for building.
"The advance is not a loan but it
does have to be paid back," said McCauley. "When a loan is
obtained, then the loan advance is paid back."
Currently, all Mona residents use
septic systems, on-site systems designed to safely dispose
of biological waste.
Septic drain fields are used to
remove contaminants and impurities from the liquid that
emerges from the septic tank. This is typically done by
burying perforated pipes in trenches and allowing the liquid
to leach out and the surrounding soil absorbs the unwanted
waste.
Bacterial action takes place in the
septic tank where the end products are mainly water, gases,
and undigested material, called sludge that sinks to the
bottom of the tank.
The sludge in the bottom of the
tank must be pumped out every two to four years, depending
on usage and tank size, and properly disposed of. If the
sludge is not removed periodically, it will eventually carry
over into the leach field and cause the field to
fail.
One common contaminates, said
McCauley, is high nitrate levels in water which come from
fertilizers and manure, animal feedlots, wastewater and
sludge and septic systems.
The allowable level of nitrogen in
water for children six months or less is 10ppm (10 mg/1) as
nitrate nitrogen or 45 ppm (45 mg/1) as nitrate. Adults and
older children can probably tolerate higher levels, but the
standard is usually set at the more conservative level.
Human waste naturally contains
coliform bacteria (for example, E. coli) and other bacteria
that can cause disease. Once water becomes infected with
these bacteria, it becomes a health hazard.
Existing home owners, he said,
should only have to pay for the collection line from the
home to the sewer lateral in the street. New developments
will need to pay an impact fee as they come into the city
and will need to install the sewer lines for service to the
system.
"There will be a monthly users fee
that you will set," said McCauley.
In the ideal case, a sewer system
is completely gravity-powered, like a septic system. Pipes
from each house or building flow to a sewer main that runs,
for example, down the middle of the street. The sewer main
might be 3 to 5 feet in diameter. Periodically, a vertical
pipe will run up from the main to the surface, where it is
covered by a manhole cover. Manholes allow access to the
main for maintenance purposes.
The sewer mains flow into
progressively larger pipes until they reach the wastewater
treatment plant. In order to help gravity do its job, the
wastewater treatment plant is usually located in a low-lying
area, and sewer mains will often flow naturally downhill to
the plant.
Normally, the lay of the land will
not completely cooperate, and gravity cannot do all the
work. In these cases, the sewer system will include a
grinder-pump or a lift station to move the wastewater up
over a hill.
"Mona will have approximately a
half-dozen homes which will need a grinder," he
said.
Depending on how committed the city
council is, said McCauley, the study could be done in six
month's time and the city could be ready to begin
construction after 18 months.
There is a lot of work to do to
that point, however. There will be public hearings and a
place will need to be determined for a sewer lagoon or sewer
treatment facility.
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