Dock De-Icers 101 - The Basics of Choosing a Dock De-Icer to Protect Your Dock From Ice Damage

In some parts of the country, ice can cause a lot ofsuspending the unit. Under normal circumstances, the
problems for dock owners. According to the boatingice will be cleared from the target area in a matter of
industry publication "Trade Only", this damagehours.
amounts to millions each year. Many private dockThere are several popular brands of in-water de-icers
owners watch in frustration each year as ice slowlythat are readily available, and they vary in unit power,
rips their dock to shreds. There are three main wasvoltage and cord length. Voltage will be determined
ice damages boat docks.by the power source available at the dock. 110v is
One way this happens is if the frozen surface of athe most common, but many docks are equipped
body of water slowly shifts with wind or current.with 220v. You will need a cord long enough to allow
This can be imperceptibly slow, but there can be ayou to position your unit in the water, but plug in to
lot of mass behind the motion - Enough to crush aa dry ground-fault interrupted power source or
dock.suitable extension cord. The connection will need to
Another common problem is heave or "Piling Jacking"be located where it is not in danger of being
which occurs when water levels change. Ice formssubmerged. Typical cord lengths range from 25' to as
around pilings during low water and then floats whenlong as 150'. The power of the unit is determined by
the water levels rise, pulling the piling from theyour typical ice clearing needs. A handy de-icer
bottom. When the water drops again, a new band ofperformance table can help you decide what size unit
ice forms at the water line and the process isyou'll need for your dock application.
repeated.As you can imagine, running one of these electric
The final source of damage occurs when loose slabsde-icing options around the clock for months at a
of floating ice, driven by the wind or currents collidetime can run up the electric bill. Many dock owners
with the dock. These battering rams don't have toset up a special thermostat or timer that controls the
be moving very fast to cause a lot of damage.operation of the bubbler or de-icer. These units are
The best way to avoid dock damage is to removelocated above the water and control power to the
the dock from the water during the winter months.de-icer unit. The thermostats will turn on when air
However, that isn't always possible. Fortunately,temperature drops below a set point, and will turn
there are a couple options to help protect docksoff when the temperature rises above a set point.
from ice. The first solution is called a "Dock Bubbler".That means that if the temperature rises above
Dock bubblers consist of a compressed air sourcefreezing for several days, or (or even for the
and perforated pipe or hose that is secured to theafternoon) the de-icer is shut down and saves
lake or river bottom around the perimeter of thepower. Note that a lot of the thermostats are
dock. If set up correctly, a bubbler will emit a curtaincalibrated either for fresh water or salt water, so
of bubbles that will cause water circulation. Themake sure you choose one that is appropriate for
bubbles will push warmer water from below to theyour application.
surface to the top, melting the ice.Timers work on a similar principal, allowing the deicer
The second option is to install an in-water de-icer.to work for several hours, then shut down for
In-water de-icers, sometimes called dock or marineseveral hours. It may take a little trial and error to
de-icers have a submersible motor ranging between 1determine the optimal time sequence for your
4 HP and 1 HP that drives a propeller. These units areparticular conditions.
suspended below the dock or from a float anchoredWhile deicers will protect against ice forming around a
just outside of the dock. In-water de-icers create adock, and can be used to form an open water break
flow of water, again, pulling warmer water fromto keep the shifting ice from crushing a dock, it
below the surface and directing it at the target areawon't protect against floating ice. In some areas,
of the surface. If suspended vertically, a dock de-ierparticularly on rivers, large chunks of ice propelled by
will create a roughly round area of cleared ice. Ifthe current or wind can act as a battering ram,
suspended at an angel they will clear an elliptical area.pummeling docks. If you are faced with this danger,
They need to clear an area larger than the dock,you may need to place protective pylons, or floating
forming open water around the pilings or floatingbooms to deflect moving ice away from the dock
portions of the structure. In-water de-icers can beand shore side structures.
installed even after ice forms, buy cutting a hole and