Careful of Pressure Ridges on Maine Lakes This Season

Pictures and posts about Pushaw Lake on Facebook this weekend had neighbors reaching out to neighbors to warn them of the danger of a pressure ridge that had developed on the lake.  Specifically, this pressure ridge was located on the Hudson side of Pushaw near Mags Point/Ledge/Lane.

A pressure ridge occurs on a lake when the ice is heated up by the sun during the day which causes expansion of the ice shelf which can cause movement and fracturing of the ice shelf.  This expansion can be alerted by moaning and groaning by the ice on the lake as well as the sound of an explosion when the ice finally succumbs to the pressure created.  You might even feel a little earthquake nearby when this happens.

The dangers that a pressure ridge occurs when it's hard to see the ridge due to a lack of contrast between the ridge and it's surroundings, so, if you come across it while snowmobiling, you could've not seen the ridge until you hit it.

It creates a large wall that stands several feet high and can be accompanied by thin or even open water along the ridge due to the fracturing of ice at the ridge.

Here's an incident where someone got lucky to escape alive having driven into the thin ice of a pressure ridge but lost their car in the process:

Here are great pictures of a pressure ridge at Sebago Lake here in the State of Maine from January 2015.