How to Winterize Your Sprinklers, Drip Systems, and Hoses

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Having water in your yard where you need it is a real blessing. Remember, people used to have to carry it by hand. But come winter, those hoses, pipes, and valves are susceptible to the cold. As the first frost approaches, it’s important to think about the steps you need to take to send your system into hibernation for the winter.

Your sprinkler, drip system, and hoses are likely made up of PVC, poly, and plastic. While those materials are fairly resilient to weather changes, the water that flows through them is not. Water becomes ice, and that’s a problem, because even durable materials are not impervious to the pressures created by the expansion of water into ice. Irrigation pipes are buried underneath garden beds, grass, and all over the yard. Tracking down a leak is a pain I don’t wish on anyone. You've likely spent money on your garden hoses, too, and replacing them becomes expensive and a pain.

Winterizing is a chore, but a vital one, and it’s not an overly difficult process. It’s also worth tackling sooner rather than later, just in case you experience a surprise early freeze.

To protect your system, your first step is to rid yourself of the water. Some systems are now built with drains at the lowest point of the system to proactively clear out sitting water, but most of us will have to blow or drain the water out ourselves.

Identify your draining mechanism

Each system is built differently. Some systems have a drain near the sprinkler shutoff valve, and that can be in your home—usually a basement, near the water heater. It will look like a hose spigot on your sprinkler line.

In other cases, your manifold has a fitting specifically designed to attach to an air compressor, so you can literally blow out all the water. Your manifold is usually in the ground, in a green and black plastic box near your sprinkler timer, and looks a little like an octopus. This is where the wires from your timer meet all the controllers for each sprinkler or drip line. Sometimes the manifold has a drain valve, which again, will look like a drain.

Get a plumber’s help

Since your average homeowner or renter isn’t a plumbing expert, consider paying for an hour of a plumber’s time to get a checkup on the system and get their advice on how best to winterize it. In many places, your backflow requires a yearly inspection, so that would be a good time to ask. You can also just hire a landscaping company or a plumber to handle the winterization outright.

Understand your pipes and valves

Your sprinkler system is a series of pipes and valves. The pipes direct the water, and the valves shut or open access to the pipes. Your pipe starts at the water main, and there’s a valve there. When open, the sprinkler line will receive water. Along the line, there will be more valves, such as at the manifold, or in each of your garden boxes. Each of the controllers in the manifold are a valve, opened and closed by your timer. When a valve is closed, water can get trapped there, and you don’t want that water to freeze.

Understanding those valves will help you understand how to get rid of the water because it’s going to involve opening and closing them. As you drain a section of pipe, it’s only draining the pipe between two closed valves.

Your sprinkler heads likely contain something called a “check valve” that allows water to flow back to the pipe, and you can access them by just manually pulling up your sprinkler heads.

Setting aside the valves, water naturally flows to the lowest point it can, so you’ve also got water sitting in pipes underground. Usually these pipes are placed below the frost line, which changes from area to area. These pipes are presumed to be safe from frost. Still, it’s best not to take chances.

Your system also might have something called vacuum breakers installed, which are part of the backflow prevention, so that water in your pipes can’t flow back into the city water. You’ll need to open these vacuum breakers in the process of draining.

How to drain your system if you have an interior drain

Start by shutting off the main valve to your sprinkler system, the one closest to your water main. If you have a drain nearby, put a bucket under it (not a small one, either, depending on the size of your system). Open the drain and allow it to run until no more water comes out, emptying the bucket as needed. Leave the bucket there for the next step.

Next, check the vacuum breakers. They might have drain caps, and you’ll need to open them to release the vacuum. Remember, because the water main is off, this water can’t flow back into the city water. You should have more water come out of the main pipe drain. This drain should remain open all winter, so leave the bucket there to catch any flow.

How to blow out your system if you have a blow out fitting

Start by shutting off the main water valve near your water main so there isn’t more water coming into the sprinkler system. Make sure any valves between the one you just closed and your blow out fitting are open, and open one of your main sprinkler or drip lines. Make sure all the valves on the other side (where the water comes out) are open. Insert the air compressor into the fitting and turn on the air. You’ll hear the water moving through that sprinkler line, but at some point, all the water will be gone and only air will come out of the sprinkler or the drip. Check all the end points for that line, and then turn the air off and close sprinkler line off while leaving the valves open. Now open the second sprinkler line and repeat the step. Do this until all the sprinkler lines have been cleared of water.

At this point, you can close the valve after the fitting, to the manifold. If there is a drain in your home, open it, place a bucket under it, return to the fitting. Blow in air, and any water between the manifold and the water main should drain out. Leave the drain open for the winter, open up the valve to the manifold, and make sure you securely screw the cap back onto the blow out fitting.

How to winterize your garden hoses

It's tempting to leave your hoses connected all winter. After all, you use them for more than watering. But hoses aren't very resilient, and you should endeavor to protect them. Start by turning off the water to the spigot, and close off all the water valves. Sometimes, this valve is inside. Disconnect the hose from the spigot, and then drain the hose. If the hose has been on a reel, unwind it all the way to ensure there isn't water trapped in it. Unkink the hose if there are any bends or kinks. Store the hose in your garage or basement, in a spot where the temperature won't drop below freezing, and then make sure to cover the spigot with an insulated spigot cover.

Reverse the process in the spring

When you’re ready to start your sprinklers again in spring, you’ll need to make sure that drain valve is closed, and then test the system. The first time you send water back through, you may hear a loud noise, which is called “water hammer,”; that’s just water pushing air out of the system. It’s perfectly normal, and is only a problem if it persists.