DENVER, Colorado — The incoming winter storm that is forecast to arrive on the Front Range Thursday and Friday has many Coloradans wondering if they should blow out their sprinkler lines early.  While the storm will be a little colder than we are used to seeing with our October storms, (into the teens for a couple of hours) it won’t be cold enough to freeze irrigation pipes that are buried under 8-12 inches of dirt, which acts as an insulator, especially with daytime highs in the upper 70s the day before the storm.  “Below ground, parts are going to be fine. The above-ground parts like your backflow preventer, those will freeze and be damaged by this storm,” said Tony Hahn, a Landscape Care Consultant with Swingle. “We’re asking people to drain those and cover them.” It’s a device that’s installed on your home’s water pipes that allows water to flow in one direction but never in the opposite direction. Its job is to prevent drinking water from being contaminated due to backflow from your irrigation system.  Step 1: Locate the valve that shuts of the water to your irrigation system and turn it to the off position. (Not the whole house, ju...