I made these tunnel frames with 32mm Class 10 HDPE
The irrigation is through 32mm Class 6 HDPE,, 20mm LDPE and vibronet misting nozzles with antidrain
Install a rain sensor
A rain sensor detects measurable rainfall and is able to turn off the automatic irrigation valves. You can buy a rain sensor almost anywhere irrigation products are sold. Most will will work any brand of irrigation controller or timer and any brand of valve.
You mount the rain sensor on the side of the house, on a pole or on the gutters in a location where water will fall on it but a sprinkler will not hit it. Then you run 2 or 3 wires from the sensor to the controller. The exact installation instruction vary depending on the brand and model of the rain sensor.