How To Install Lawn Irrigation

Keep your grass healthy and green by installing a simple watering system. 

An automatic watering system has become a viable way to give your lawn the water it needs without wastage. 

The type of pop-up sprinklers you choose will depend on the flow rate of your local water supply, which can easily be calculated by timing water as it flows into a bucket. 

You will also need to sketch a scale diagram of your lawn, including the position of larger trees, any shady or sunny areas and slopes where water may run off.

Fine-tune the system

When the system is set up, attach a timer and position small containers in different parts of the lawn.

Time how long it takes for the containers to fill up with water about 30 to 40mm deep and set the timer for this number of minutes. 

Water penetrates clay soils more slowly than sandy soils so they should be watered at a slower rate to reduce runoff. The system should also be adjusted in winter when the lawn won’t need as much water.

Dig wisely

Even for a small-scale project like this one, it’s essential to dial 1100 before you dig or visit 1100.com.au to locate any underground utilities. 

Mark these on your diagram to prevent disasters like putting a shovel through a pipe or cable.

When the trenches have been backfilled, reseed the bare patches, or for running grasses you can just wait until they spread to cover the soil. 

Add some turf fertiliser and water regularly, keeping weeds at bay so the grass has a chance to grow.  

Diagram 

Install lawn irrigation diagram, Handyman magazineHow to install lawn irrigation 

Step 1. Measure the flow rate

Position a bucket under the tap that will supply the system and open fully for exactly 10 seconds. Measure how much water is in the bucket and multiply the number of litres by six to find the flow rate in litres per minute.

Step 2. Set out the system

Unroll the poly pipe on the surface of the lawn and position the pop-up units, elbows and T joiners according to your planned setout.
TIP Leave the pipe in the sun to soften slightly so that it is easier to uncoil.

Step 3. Dig the trenches

Excavate trenches deep enough for the sprinklers to finish at ground level then position the pipe in the trenches.
TIP To get poly pipe under a path, tap in a length of 50mm galvanised pipe, pulling it out to clear every 200mm.

Step 4. Connect the parts

Assemble the system, including the timer and backflow preventer, using ratchet clips to secure the joints. TIP The backflow preventer stops dirt being sucked back into the potable water supply if there’s a pressure drop.

Step 5. Install the sprinklers

Install the sprinklers, packing the soil firmly around the sprinkler heads to hold them in position. TIP Bury the heads slightly lower than the surrounding lawn surface to avoid damage from lawnmowers.

Step 6. Test the system

To flush out any dirt in the pipes, turn the tap on before adding the end sprinklers. Inspect the system for leaks and rotate the heads to keep the entire spray pattern over the lawn, instead of overlapping any hard surfaces.

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