The City recommends backflow freeze protection
It doesn't happen very often here in Southwest Florida, but you can be prepared for it when the freezing temperatures come. While the recorded temperature may not drop below freezing, the wind chill can still cause freezing. Should this occur, your above-ground backflow device may freeze due to the location and exposure of the device. Therefore, the Utilities Department recommends you winterize your backflow device to protect it from a frost or freeze should it occur.
The responsibility of protecting the backflow device is that of the customer. By taking a few simple precautions, you can save yourself the mess, money and aggravation.
Prevent and protect your Backflow Device by using the following "Do-It-Yourself" guidelines:
• Insulate exposed pipes which are most susceptible to freezing. Remember the more insulation you use, the better protected your pipes will be. You can use specially-designed pipe insulation bought from your local hardware store. You can also use blankets, old clothing, several sheets, or any other material that will keep the cold wind off your exposed pipes. Just remember to cover ALL exposed areas and secure them with a garbage bag and duct tape or even metal wire to prevent the insulating material from coming off. Another inexpensive way to do this would be to cover the device with burlap type material and cover with black roofing felt or material similar to that used to protect flowers and plants from frost. There are products available such as a decorative fiberglass rock that would cover the device year round and be aesthetically pleasing for your property. These are available at home improvement and agricultural supply outlets.
• Do not remove the pipe insulation until the temperature rises above 32 degrees! You may want to leave the insulation for the remainder of the winter season so you'll always be ready and prepared.