Water bill rising, Binky?
I can feel your pain. Ours is going up, too.
Very few regions of the world still have cheap, plentiful water—except maybe the rainforests. If you live in an area that requires watering your grass, plants and trees, we’ve begun to see the last of the old days of spraying your yard with a hose, or irrigating it with periodic flooding, or moving the oscillating sprinkler from place to place.
Instead, in-ground sprinkler systems have become the norm. They save water, promote healthy plant growth, can be easily regulated with automatic timers, and best of all, they minimize runoff and save you money.
If you’re a handy, hardy do-it-yourselfer with the know-how, a strong back, the tools and the time, you can probably install an in-ground sprinkler system yourself. It’s not rocket science, but it isn’t simple, either, and a fair amount of ditch-digging, labor-intensive spade- and shovel-work is involved.
So follow along with this 9-step outline for installing an automatic sprinkler system, and then decide if you’d like to attempt it as a DIY project, or hire your local contractor and let the pros do it.
1) You’ll need to check to see if your area requires a building permit, and then call your local utilities to ask about underground pipes. Don’t skip that last part—it’s the law. Every excavation, even digging a hole in your own yard, requires checking with your utility. Digging into an underground gas line will end your project, or even your life, quite prematurely.
2) You’ll need to do some measuring—of your water pressure (in psi—pounds per square inch); your water meter and supply line size; and your water flow rate (in GPM—gallons per minute). A good landscape contractor or plumber can tell you all these things in a few minutes.
3) You’ll need to find out what kind of backflow prevention your local code requires. The local hardware or home improvement store can usually provide this information.
4) Begin laying out your sprinkler system--on paper, and to scale. Map your yard so it takes into account your shrubs, bushes, trees, lawn and flower beds. Every in-ground sprinkler system has separate zones, which you can set independently in terms of watering duration. It’s important to map out these zones so they water similar areas according to the needs of the plants there. Draw your map in straight lines, the same way you’ll lay out your pipe underground.
As soon as you have your yard mapped, figure out where you need to place the actual sprinkler heads along the route of the water pipes. Remember that sprinkler heads come in different spray patterns, and plan for 100% coverage of everything that grows—no dry spots.
Now you’re ready to hit the hardware store.
5) Buy the components of your system to match your water pressure readings and your water supply line. Here your local hardware store expert can usually help, guiding you to the right products that fit your system. You’ll need: valves to regulate the water flow (either automatic or manual); lots of PVC or polyethylene pipe (get more than you think you’ll need); pipe glue; a backflow preventer; fittings, couplings and risers; sprinkler heads; and a valve manifold to control the entire system.
6) Here comes the hard work: digging the trenches to bury your system’s pipes. Dig trenches deep enough to allow the sprinklers to retract sufficiently to avoid mower blades and weed-whackers; and to avoid freezing in the winter—usually a foot or less. Make your trenches level to keep the sprinkler heads even, and save the sod so you can repair your trenches when you’re finished.
7) Once you’ve finished trenching, lay out the pieces of your system and pre-assemble the parts. Connect the PVC pipe with primer and PVC cement, being careful to use reference marks to align the pipes and their joints correctly. PVC glue is permanent, so take care to assemble correctly the first time.
8) Once the pipes, joints and risers are assembled, and the manifold, backflow preventer and valves are hooked up to a water supply (you may want a professional to do this part), turn the system on to flush it and check for leaks. Then thread the sprinkler heads onto the risers, and adjust their spray patterns so no plant dies of thirst.
9) And for the final step, if your system includes electric timers, plug it in and set it so each zone gets the proper amount of water—usually about 1-2 inches a week, depending on your plants. Some in-ground systems also include moisture and temperature sensors, another great way of saving water, time and treasure.