This time of year some dock owners are considering the use of De-Icers . These devices are used to keep ice from forming around docks and submerged structures during the colder months that stay underwater year round. De-Icers are designed to prevent the water around the structure from freezing with the intention of reducing the damaged caused by ice and fluctuation water levels. However many folks may not understand the impacts these devices have on the environment, some of the danger involved, legal issues and permitting issues, or the social issues related to the use of De-Icers.
A better understanding of these issues can greatly reduce these hazards, save energy, better protect your structure and the environment while helping you to be better neighbor.
-Many NH municipalities require a permit to install a De-Icer as well as signage to be present and visible and must read "Danger, Thin Ice".Make sure you check first!
-Folks ski, skate and snowmobile on Squam in the winter. Unposted thin ice and open water is a danger not only people but to dogs and wildlife as well.
-It's best to install a De-Icer with a controller to regulate when it kicks on, this will save energy, money, reduce noise impacts and will help to prevent unintended areas of thin ice or open water
-The lake "rests" in the winter. If not set correctly a De-Icer can stir up sediment reducing water clarity (and possibly undermine your dock!)
-Without a layer of ice and snow more light will reach the lake bed and can warm water temperature, potentially promoting algae and weed growth.
-Avoid using a "circulator" de-icer. This style uses propellers to move the water to prevent freezing. Besides creating often times unpredictable thawing effects in areas you didn't intend they require relatively large motors using significant amounts of energy and create noise. Consider a bubbler system instead. These systems better target specific areas, are quieter and cheaper to operate.
The folks at the Lake Sunapee Protective Association have created the Dock De-Icers: Tips for Safe and Effective Use brochure for further information.