WINTER KILL
Oxygen Demand in Ice Covered
Lakes as It Pertains to Winter
Aeration
Christopher R. Ellis and Heinz G.
Stefan
Oxygen consumption and thus
depletion is a function of oxygen
concentration and velocity of
near sediment water
Winterkill Lake Facts
• Stratify quickly after ice cover.
• Oxygen consumption is greater than production.
• Oxygen production slows or ceases as light
penetration decreases.
• Oxygen consumption is greatest at the water
sediment interface.
• Oxygen consumption decreases as oxygen
concentrations fall below 3.8 ppm.
How to cause a winterkill
• We need to destratify the lake/wetland.
• We need to create currents that cause the
oxygenated water on the top to go to and move
along the bottom.
• Need to make sure our actions are not increasing
the amount of oxygen in the system.
Reverse Aeration
REVERSE AERATION
Reverse aeration is the use of lake
aeration techniques that increase the
oxygen concentration and velocity of
near sediment water which increases
oxygen consumption and depletion
Water currents (convection)
Diagram of water flow during aeration operation
Questions?
Equipment Needs
• Two complete systems ($5,000)
Equipment Needs
• Two complete systems ($5,000)
• Generator ($1,300)
Additional Equipment
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Do meter
Hand held depth finder
8-inch ice auger
Ice chisel
Snow shovel
Repair tools for the poly tubing
Mud motors
Questions?
How to approach a project.
Questions?
SAFETY FIRST!!!!!!
Safety Equipment
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Floatcoat or life jacket
A throwable flotation device
Life guard spikes
Ice creepers
Rope
Ice chisel or board for probing the ice