Few things are more annoying than a drip system that has run perfectly for months and then suddenly stops watering half the garden. Almost every drip failure traces back to one of a handful of causes, and most can be diagnosed in under ten minutes.
1. Clogged Emitters (The Most Common Cause)
If some emitters flow and others do not, clogging is the prime suspect. Causes include mineral scale, algae, and sediment from a missing or dirty filter.
Fix: Unscrew or pull the affected emitters and soak them in a 50/50 mix of white vinegar and water for an hour. Then flush the entire line by removing the end cap and running the system for two minutes. Add a 150-mesh filter if you do not have one.
2. Low Pressure at the Far End of the Line
If the first emitters spray strongly and the last ones dribble, you are losing pressure over distance. This is normal friction loss, and it gets worse on slopes.
Fix: Switch to pressure-compensating emitters, split the run into two shorter laterals, or move to a larger-diameter mainline. A 25 PSI regulator at the head also helps stabilize the whole system.
3. Leaks at Connections
Barbed fittings leak when the hole was punched too large, at an angle, or when the tubing was not pushed fully onto the barb.
Fix: Cut the damaged section out and reconnect with a coupler. Always punch holes perpendicular to the tubing, and push fittings in until you feel them seat.
4. Rodent and Insect Damage
Mice and voles chew drip tape, especially when it is buried with mulch on top. Cricket and earwig damage concentrates at the emitters.
Fix: Use heavier-gauge tape in rodent-prone areas, keep mulch away from direct tape contact, and repair chewed sections with two barbed couplers and a short replacement length.
5. The System Will Not Turn On
- Check the controller — a dead battery or a blown fuse in the transformer stops everything
- Check the valve solenoid — listen for a click when the zone activates
- Check for a closed shutoff — a ball valve left partly closed after winterization is a classic
- Check the filter — a fully blocked filter behaves exactly like a closed valve
A Quick Diagnostic Table
| Symptom | Most likely cause | First thing to try |
|---|---|---|
| Some emitters dry | Clogging | Vinegar soak + flush |
| Weak flow at line end | Pressure loss | Switch to PC emitters |
| Water spraying at joints | Bad punch/connection | Cut out and recouple |
| Nothing runs | Controller or valve | Check battery and solenoid |
| Sudden drop in flow | Blocked filter | Clean or replace filter screen |
Preventive Maintenance Schedule
- Monthly: Inspect the filter and clean the screen
- Monthly in season: Flush every lateral for two minutes
- Seasonally: Check emitters for scale and soak as needed
- Before winter: Drain and blow out the system to prevent freeze damage
Bottom Line
Ninety percent of drip problems are clogging, pressure loss, or a blocked filter. Learn to check those three first and you will solve most issues in minutes instead of replacing parts at random.