Myths about dugout aeration
Dugouts provide water for a wide variety of farm
uses, including domestic supplies, livestock watering, crop spraying
and more. Aeration is generally accepted
as an inexpensive way to improve dugout water quality. After working on farm
dugouts for more than 65 years, PFRA has identified a number of myths. This
debunks some of the more common myths about dugout aeration.
Myth: You do not
need a diffuser to aerate a dugout effectively.
- Fact: A diffuser
dramatically increases the effectiveness of any aeration system.
PFRA data show that oxygen levels in dugouts aerated
with a diffuser are twice
as high as those in dugouts aerated without a diffuser. A diffuser
is relatively inexpensive compared to the cost of a compressor,
and by including it as
part of your aeration system, you can improve your dugout's
water quality significantly.
Myth: A diffuser should be elevated
from the bottom of the dugout.
- Fact: Placing the diffuser on the
bottom of the dugout at its deepest point produces the best aeration
and the highest quality
While a diffuser may temporarily stir up some sediment, it
produces the best long-term results when placed directly on
of the dugout.
that diffusers do not mix water located below their elevation and the
sediments release nutrients when they come in contact with poor quality
water, the diffuser
should be located in the deepest part of the dugout.
Myth: The diffuser
should be located near the water intake to get the best possible
- Fact: The diffuser need not be located near the intake.
If the aeration system is working properly, the water in the dugout
be well mixed
in quality. So the placement of the diffuser relative to the water
intake is not
important in an aerated dugout.
Myth: You should only aerate at night
- Fact: While it may be possible
to get away with aerating only at night, or for part of each
day, aeration systems produce the
hours per day.
Besides, aeration systems operate longer and are
more trouble free when they are operated continuously. Turning
the system on and
tear on the compressor and the motor and will ultimately shorten
the lifespan of these
running parts. Over the long run, this wear and tear will cost
more than the energy required to operate the system 24 hours
Myth: You should only aerate in the winter.
- Fact: While it
is generally recognized that aeration can improve dugout water
quality during the winter, aeration can
during the summer. By maintaining a high level of oxygen,
aeration reduces the risk
of plant nutrients being released from the sediments, the
chances of a blue-green algae bloom and the creation of taste and
maintaining good water quality during the summer, you improve
of the dugout
to avoid water quality problems in the winter.
shows that aeration systems produce the best results when they
are operated 365 days per year. In fact,
continues to improve for up to five years after an aeration
system is installed in a
dugout and operated continuously.
Myth: Aerating dugouts in
the summer heats up the water.
- Fact: The temperature of the water
in a dugout is determined primarily by how much radiant energy
the dugout receives from
the sun. Things
the amount of shade provided by nearby trees have a much
greater effect on water temperature than aeration.
It takes 1000
times more energy to increase the temperature of water than air.
Therefore, aeration will not significantly
temperature of the
water in a dugout. PFRA experiments show no significant
difference in temperature
aerated versus non-aerated dugouts.
Many farmers who raise
fish in their dugouts during the summer are concerned that aeration
will warm the water and make
it more difficult
fish to survive. In fact, summer aeration will prevent
the development of conditions
that can lead to fish kills.
Myth: Aeration creates open water
or thin ice making the dugout unsafe
- Fact: Aeration produces thinner
ice and sometimes open water only over the location of the diffuser.
The extent of the
on the type
of diffuser used. Linear diffusers generally produce
the least amount of open water, while the complete absence
of a diffuser
most. Data collected
from a large number of dugouts show that the ice returns
to normal thickness just a metre or two away from the
If the safety of children and animals, including pets,
is a concern, the dugout should be fenced. Always exercise
Myth: Aerating dugouts in winter cools the water
and results in thicker ice.
- Fact: There is no difference between
ice thickness on aerated and non-aerated dugouts. Thickness of
snow on the dugout
is the overwhelming
determining ice thickness.
Some rural residents are
concerned that thick ice reduces the amount of liquid water available
for use during the
Data collected over many years from a
wide variety of dugouts show no statistical difference between
non-aerated dugouts. The
data does show that ice thickness is determined primarily
by the snowfall patterns.
A thick layer of snow shortly after freeze-up provides
insulation and prevents the formation of a thick layer
Myth: You must have open water in the winter in
order to have a well aerated dugout.
- Fact: The best aerated dugouts
have little or no open water. The aeration system pumps air to
of the dugout
and so open
water is not
needed to get
oxygen into the dugout.
Data collected from a large
number of aerated dugouts shows that the highest concentrations
in the dugouts
no open water.
The amount of open water is determined
by the type of diffuser and the overall efficiency of the aeration
as air stones
create a lot of turbulence at the surface and help
prevent ice formation. Open water is also maintained
if the aeration
from the bottom of the dugout to the surface, preventing
ice formation. An effective
aeration system mixes all of the water in the dugout
and maintains a constant temperature throughout.
With a good
no warm water
to bring to the surface to prevent ice formation.
Dugouts represent an important water source on the
Prairies. They are used to provide water for drinking,
spraying and aquaculture. Each of these uses is affected
by water quality. Therefore,
it is important to maintain the best possible quality
of water in your dugout.
Aeration is one of the many
tools available to improve dugout water quality. Other techniques
the dugout and controlling inflows to the dugout.
Regardless of what tools might
dugout water is not safe for human consumption
without additional treatment and disinfection. Aeration can
however reduce the
cost of these treatment
processes and make them more effective.
is generally accepted that aeration can improve dugout water quality,
a number of myths
It is important
the facts when designing and operating an aeration
For more information on dugout aeration see the
following Water Quality Matters publications: "Why
Aerate Your Dugout" and "How To Aerate
For further information on
rural Prairie water quality and treatment technology:
- contact your local Prairie Farm Rehabilitation Administration
office (PFRA is branch of Agriculture
- read Prairie Water News, available
from PFRA, or on the Internet at www.quantumlynx.com/water