How to install a pop-up sprinkler system

A well-installed pop-up system waters the lawn evenly, on schedule, and disappears into the turf when it’s off. A rushed one leaks at the fittings, sprays crooked, leaves dry strips between heads and spends its first summer with blocked nozzles.

This guide covers the hands-on work of putting a system into an existing lawn. It assumes you’ve already planned it: zones, head positions, pipe sizes and how much water your supply delivers. If you haven’t, start with the DIY lawn irrigation design guide. A good plan is most of the work; the digging is the easy part.

Before you dig

• Have a plan on paper. Every head, valve and pipe run, drawn to scale, with the heads and nozzles chosen and checked against your water supply’s flow.
• Contact Before You Dig Australia. It’s a free service that tells you where underground pipes and cables are, so you don’t hit water, gas, power or telecommunications lines.
• Check your water authority’s requirements. Work on the connection to the mains supply, including backflow prevention, may need a licensed plumber. Your water authority’s rules will also set when you can run the system.
• Check with your council before doing any work on the nature strip or near the street.
• Choose the season. Install while the lawn is actively growing, so the trench lines recover quickly.
• Buy one range of heads and nozzles, so part-circle and full-circle heads on each zone apply water at matched rates.

What a typical system includes

From the tap or water supply outwards:

1. The connection to the water supply, with an isolation valve to turn the whole system off and backflow prevention to protect the drinking water supply.
2. A filter, to catch grit before it reaches the valves and nozzles.
3. A valve box holding one solenoid valve for each zone.
4. Main pipe from the connection to the valves, and lateral pipe from each valve to its heads.
5. Pop-up heads on flexible risers or swing joints, so they can be set at the right height and survive being knocked.
6. A controller, wired to each valve, and a rain sensor if your controller supports one.

Power and Water’s Living Water Smart program notes that upgrading from tap timers to a controller usually means installing an isolation valve, a backflow prevention device and solenoid valves for each zone.

Step 1: Mark it out

• Mark each head position with a flag or a dot of marking paint, measuring from your plan.
• Mark the pipe runs between them with a string line or paint.
• Mark the valve box position, somewhere you can reach easily but where it won’t be in the way of mowing or play.
• Walk the layout and check it against the plan. Look for trees, paths and garden beds that weren’t on the drawing.

Before digging, place a few heads loosely on the surface and run a hose to them if you can. It’s much easier to move a flag than a trench.

Step 2: Lift the turf and dig

1. Cut the turf along each pipe run with a flat spade, in a strip a little wider than the trench.
2. Roll or lift it in sections and keep it in the shade, lightly watered, so you can lay it back later.
3. Dig the trenches to the depth the pipe manufacturer recommends, and deep enough that aerating, edging and garden work won’t reach the pipe. A hired trencher saves time on larger lawns.
4. Put the soil on a tarp beside the trench so it doesn’t smother the lawn.
5. Keep trenches safe if you leave them open overnight. Cover them or fence them off from children and pets.

Step 3: The connection and valves

• Install the connection, isolation valve and backflow prevention as your water authority requires. Where this needs a licensed plumber, have it done before you connect the rest of the system.
• Fit the filter downstream of the connection.
• Assemble the valves in the valve box, following the maker’s instructions, with room to reach each one for maintenance.
• Leave space in the box for one more valve if you might add a zone later.

Step 4: Lay the pipe

1. Lay the main pipe from the connection to the valve box, then the laterals from each valve to its heads.
2. Cut pipe squarely with proper cutters, and remove any burrs.
3. Join pipe with the fittings and method the manufacturer specifies. Fittings that are pushed on part-way leak or pop off under pressure.
4. Keep dirt out. Cap or tape open pipe ends while you work.
5. Leave a riser point at each head position, rising to just below the surface.

Step 5: Flush the pipes

Before fitting any heads, turn on each zone and let water run through the open risers until it runs clear. This flushes out soil, pipe shavings and grit. Skipping it is the most common reason a brand-new system has blocked nozzles on its first run.

Step 6: Fit the heads

1. Connect each head to its riser with a flexible riser or swing joint.
2. Set the height so the top of the head sits level with the soil surface. Too high, and the mower breaks it; too low, and grass grows over it and blocks the spray.
3. Keep heads upright. A tilted head throws water unevenly.
4. Fit the right nozzle for each position: quarter-circle in corners, half-circle along edges, full-circle in the middle, and strip nozzles along narrow areas.
5. Pack soil firmly around each head so it doesn’t lean or sink.

Step 7: Wire the valves

• Run the controller cable in the trench beside the main pipe to the valve box.
• Connect each valve with waterproof connectors made for buried irrigation wiring. Ordinary electrical connectors corrode.
• Label each wire with its zone.
• Mount the controller near a suitable power point. Any new power point or fixed wiring at mains voltage must be done by a licensed electrician.

Step 8: Test before you backfill

With the trenches still open:

1. Run each zone and look for leaks at every fitting.
2. Check every head pops up fully and sprays its full distance.
3. Adjust the arcs so part-circle heads water the lawn and stop at paths and fences.
4. Adjust the radius so each head’s spray reaches the next head.
5. Look for dry gaps between heads. Fix them now, while the pipe is exposed.

Step 9: Backfill and repair the lawn

1. Backfill in layers, firming each one gently, so the trench doesn’t sink later.
2. Water the trench to help the soil settle, then top up any low spots.
3. Lay the turf back along the trench lines, pressing it down firmly so it meets the soil.
4. Topdress any gaps with a little sandy soil.
5. Water the repaired strips like new turf until they root.

Step 10: Test and set the schedule

Once the lawn has recovered, do a catch-cup test on each zone. It shows how much water each zone applies and whether the coverage is even. Use the results to set run times with the Sprinkler Run-Time Calculator.

Then program the controller:

• Your water authority’s allowed days and hours. Icon Water’s permanent measures in Canberra, for example, set the hours sprinklers can run in the warmer months and prohibit watering that pools or runs off.
• Cycle and soak on clay soil and slopes.
• A rain delay or rain sensor.
• Seasonal adjustment, to scale run times down in autumn and up in spring.

Sydney Water warns that automatic systems that aren’t well designed, programmed and maintained can use more water than a garden needs. The installation isn’t finished until the schedule is right.

After installation

• Check heads after a few weeks, once the soil has settled. Raise any that have sunk.
• Mark heads near edges so they’re easy to avoid with the mower and line trimmer.
• Keep a drawing of where every pipe, valve and cable actually went. It saves hours when something needs repairing.
• Run each zone every spring and walk the lawn while it runs.

Common mistakes

• Digging before checking for underground services.
• Skipping the flush, so the first run blocks every nozzle.
• Setting heads too high, where the mower breaks them.
• Mixing sprinkler types or nozzle brands on one zone.
• Backfilling before testing, then digging it all up again to fix a leak.
• Using ordinary connectors for buried valve wiring.
• Never doing a catch-cup test, so run times stay a guess.

Log it

Log the installation in your Lawn Journal, with the zones, heads and nozzles, and a photo of the open trenches. Then log your catch-cup results and the run times you set. When something changes, you’ll have a record of what the system was designed to do.