Missoula’s freezing weather can leave water trapped in drip tubing, filters, valves, and other exposed parts. When that water freezes, it can damage components and create leaks when the system starts again in spring. Before temperatures drop, take time to shut down the system, remove or drain water where possible, and protect parts that cannot be brought indoors. The right steps depend on your setup, so check the manufacturer’s guidance and take extra care with compressed air.
Shut Down the Water Supply
Turn off the irrigation system’s water supply before the ground freezes. If the drip system connects to a hose bib, disconnect the hose or adapter and follow the faucet manufacturer’s instructions for winter protection. For a system connected to a dedicated irrigation line, close its shutoff valve. Don’t force a stiff or corroded valve; a damaged shutoff can create a leak.
If your system has an automatic timer, switch it off or set it to a winter or rain mode. Remove batteries if the manufacturer recommends it. For a timer attached to an outdoor faucet, bring it indoors when practical. Keep the timer and its connections dry, and don’t assume the timer’s shutoff feature drains water from the downstream tubing.
Drain Lines and Components
Open the system’s end caps, flush valves, or drain points to let water run out. Where the layout allows, lift low sections of flexible tubing so trapped water can flow toward an open end. Disconnect removable filters, pressure regulators, and backflow components according to their instructions, then drain and store them somewhere protected from freezing.
Drip systems often include low spots and small fittings that hold water even after the main line drains. Inspect exposed tubing, tees, emitters, and connectors, and remove components that the manufacturer identifies as removable. Avoid pulling on brittle tubing or forcing apart fittings. If a backflow device or valve assembly has a specific winterizing procedure, follow its instructions or ask an irrigation professional.
Use Compressed Air Carefully
Some systems can be cleared with compressed air, but this method can damage drip tubing and emitters if pressure is too high. Use it only when the system and component manufacturers allow it, and follow their pressure limits and instructions. Never connect an air compressor directly without the correct fittings and a way to control pressure.
If you are unsure about the system’s layout, pressure rating, or backflow protection, skip the air compressor and get qualified help. Keep people away from open emitters and outlets while clearing a line. Compressed air can send debris or fittings flying, and a small drip system may not need this method if it can be drained safely.
Protect Exposed Parts
After draining, protect exposed valves, filters, and above-ground pipe from wind and freezing temperatures. Use insulation designed for outdoor plumbing, keeping it dry and secured without crushing tubing or blocking access to valves. Insulation slows heat loss but does not remove water, so pair it with proper draining rather than treating it as a substitute.
Walk the system once more before winter settles in. Check that the supply is off, open drain points are left in the position specified by the manufacturer, and removable parts are stored indoors. Note any cracked tubing or worn connectors so you can repair them before spring startup. Missoula Dripworks can help assess a system if you are unsure which components need attention.
A careful shutdown helps reduce the chance of freeze damage, but every system has its own layout and instructions. Turn off the water, drain accessible parts, protect exposed components, and use compressed air only when the system supports it. If you want help checking your setup before winter, contact a local drip irrigation professional.