In extreme sub-zero temperatures, it is advisable to let the water run at a constant trickle until the temperature rises. Lower lake water temperatures combined with cold air movement around plumbing fixtures can create freezing in water lines. Under these conditions, water can freeze in the lines in just a couple of hours. To avoid this problem, try to eliminate cold air drafts on pipes and/or water meters. Use some form of insulation around the exposed pipes and meter, along with sealing areas that allow cold air movement. Also, if pipes are located against exterior walls, expose them to the warm air in the house. If the kitchen or bathroom sink is located against an outside wall of the house, leave the cabinet door open in order to allow warmer air to circulate around the pipes.
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