Name of this film 80s could be 70's
OK this is a long shot but ill give it a whirl. Could be sci-fi or horror. I remember that this lake had a monster in it according to the towns people. And the lake would bubble and something would pop up out of it. Well at the end they found out that it was an old backo floating everyonce in a while due to gases from the earth. The hand of the backo would come out of the water mistaking it for a monster. Anyway I remember a kid getting caught under neath of it. And got rescued. Also I remember the cover of this box had a backo hand with weeds all of it coming out of the water. Can anyone help on the name of this movie