Turn off irrigation systems and if you have a master valve you may want to turn …

Turn off irrigation systems and if you have a master valve you may want to turn that off as well. Above ground back flow prevention and filtration systems will freeze and break. If you have above ground water features that are not heated such as water falls of recirculating fountains you may need to turn them off and possibly drain ceramic urns to keep them from bursting. If the pumps are running and all the water freezes up the pump may run dry and burn out.
Mark Barnett – TNLA Certified Nursery Professional Proffetional

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