Winter storms are coming — drain your sprinkler system now before it freezes and cracks

Why draining your sprinkler system matters

Your sprinkler system holds water in pipes, valves, and the backflow preventer even after you stop using it for the season. When temperatures drop below freezing, that trapped water turns to ice and expands with tremendous force. The pressure is strong enough to crack pipes, split metal fittings, and destroy your backflow preventer.

Cracked underground pipes mean digging up your yard to find and repair the damage. A single night of freezing temperatures can turn a one-hour maintenance task into a major repair project come spring. Draining removes the water before it has a chance to freeze, eliminating the risk entirely.

1. Shut off the water supply

Locate the valve that controls water flow to your sprinkler system. You'll typically find it inside a green utility box in your yard, often positioned near the water meter. Open the box and identify the valve, then turn it perpendicular to the pipe — this sideways position means it's off.

Be certain you're shutting off only the sprinkler line, not your home's main water supply. If you're uncertain which valve controls what, refer to your installation paperwork or contact the company that installed your system. This step prevents fresh water from entering the lines while you drain the existing water.

2. Open the drain valves

Your sprinkler system has drain valves positioned at low points throughout the network where water naturally collects. These valves sit inside small boxes buried around your yard.

Turn each valve counterclockwise to open it. Water will begin flowing out immediately. This releases system pressure and starts removing standing water from the pipes. Keep these valves open throughout winter so any moisture that enters can drain freely instead of freezing inside your pipes.

3. Drain the backflow preventer

The backflow preventer is the above-ground device near where your sprinkler system connects to your home's water supply. It features two valves and two small drain screws on its sides. This component is costly to replace, making it critical to prevent freeze damage.

Turn both valves to a 45-degree angle, positioning them halfway between fully open and closed. Use a screwdriver to open the two side drain screws. Water will drip out gradually. Ensure the device is completely empty before freezing temperatures arrive.

You should also check for automatic or manual drains. Some sprinkler systems include automatic drains that activate when water pressure drops. If your system has these, they should have started draining when you shut off the water supply. Wait 30 minutes to an hour, then check the valve boxes to confirm water has drained.

Systems with manual drains require you to open low-point valves yourself so gravity can pull water out. Walk your property and locate any low-point drain valves, opening each one you find.