How to Install a Water-Saving Drip-Irrigation System

In this video, This Old House landscape contractor Roger Cook helps a homeowner install a water-saving drip-irrigation system.

Installing drip-irrigation

1. Use flat-blade shovels to remove the gravel from the yard and form shallow trenches. Don’t cut through the black plastic below.
2. Excavate trenches from the existing main water line across the yard and around every shrub and tree.
3. Connect an electric solenoid valve to each zone of the main water line.
4. Attach a pipe with backflow preventer to each solenoid.
5. Add another length of pipe and then install a pressure-reducing valve.
6. Open the valve to flush out dirt and debris from the main water line.
7. If necessary, dig below the sidewalk and push a length of 1½-inch-diameter PVC pipe underneath the sidewalk.
8. Feed the main feeder line from the valves through the PVC pipe and along the trenches.
9. Hold the tubing in place with metal staples spaced 24 inches apart. Use a small sledgehammer to tap in the long staples.
10. Use a utility knife to cut through the main feeder line.
11. Push a three-way barbed T-fitting into the cut end of the feeder line. Secure the line with a metal crimp clamp.
12. Attach the other end of the feeder line to the opposite side of the three-way fitting.
13. Onto the final barbed end of the three-way fitting, connect a feeder line that extends out to the nearest tree or shrub.
14. Trim the end of the feeder line to length, then push on a 90-degree elbow. Secure the elbow with a crimp clamp.
15. Onto the elbow connect a length of flexible drip-irrigation tubing.
16. Lay the tubing into the trench around each tree and shrub.
17. Secure the tubing with staples spaced 24 inches apart.
18. For larger trees, install two irrigation lines.
19. Run a feeder line alongside the sidewalk, then add drip-irrigation lines to water each nearby shrub.
20. Punch the emitter into the ½-inch-diameter feeder line, then attach one ¼-inch-diameter drip-irrigation line for each shrub.
21. Install an electronic smart controller in the garage and program it for optimum water usage.
22. On the house roof, install a sensor that detects air temperature and rainfall. The sensor will determine when to turn the sprinkler system on and off.
23. Backfill the trenches with gravel.
24. Blow out the sprinkler system with air, then turn on the water.

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