White Bear Lake Dive on March 6, 2010

[mattd]

We would augur a hole to check for depth.  That also lets us see how thick the ice is.  If the spot looked good, then the hole would be cut a few feet from the test auger hole and it works like a vent.

Terry does have the bar on his saw marked.

If you are diving pretty close to the hole, the vent really helps.  At Minnetonka over one of the wrecks, the main hole was like a hot tub there was so much air bubbling up after a few divers.  When we cut a vent, the amount of trapped air actually shot water several feet in the air.