Winterization of the plumbing system can help prevent significant damage caused by frozen water inside pipes, and ensure the safety of the entire plumbing system in winter. The average temperature in Denver during the winter season can go as low as -7 degrees Celsius. This freezing temperature not only tests the human endurance but also that of the plumbing systems of Denver homeowners too. Apart from all the problems they are going through, they have an extra worry of frozen pipes.