Why a Sprinkler Head Geysers and What to Do About It

A geyser in your lawn is hard to miss. Instead of a neat spray pattern, a column of water shoots straight up or bubbles up from the ground around a head. It wastes water, can flood nearby areas, and robs pressure from every other head on the zone. This article explains what causes geysers and how each cause is fixed.

What a Geyser Tells You

A geyser means water is leaving the system without passing through a nozzle. That can happen at several points:

• At the top of the head, where the nozzle should be
• At the riser, the part of the head that pops up
• At the head body, which sits in the ground
• At the fitting that connects the head to the pipe
• In the pipe near the head

Where the water comes from tells you which part has failed.

Cause 1: Missing or Broken Nozzle

If water shoots straight up from the top of the riser in a narrow column, the nozzle is often missing or cracked. Nozzles can pop off after being hit by a mower or edger, or wear out over time.

Fix: Turn off the zone, find the correct replacement nozzle, clean the filter screen, and screw the new nozzle on. Match the arc and throw to the head’s position.

Cause 2: Broken Riser or Cap

If water comes out around the top of the head body, the cap may be cracked or the riser broken. This often happens when a car rolls over a head or a mower hits it while the head is up.

Fix: Replace the head. On most spray heads, the whole head is inexpensive enough that replacing it makes more sense than repairing the internals.

Cause 3: Head Knocked Off the Fitting

If water bubbles from the ground around the head, or the head body is tilted or loose, the head may have broken off the fitting below. This is common near driveways and curbs, where vehicles hit heads.

Fix: Dig out the head and inspect the fitting. Replace the fitting and the head as needed. For heads near traffic, a swing pipe connection gives some flexibility so the next hit is less likely to break anything.

Cause 4: Cracked Pipe Near the Head

If water surfaces a foot or two away from the head, the lateral pipe may be cracked. On clay, water can travel before it comes up, so digging a bit wider than you think helps. Our guide on broken sprinkler pipe repair explains how pipe repairs are done.

Cause 5: Freeze Damage

Heads and fittings with water trapped in them can crack during a hard freeze. The damage often does not show until the system is turned back on. If several heads geyser in spring after a cold winter, freeze damage is a likely cause. See our article on freeze damage after a hard freeze.

Why a Geyser Affects the Whole Zone

A zone has a limited amount of water flowing to it. When one head has an open break, a large share of that flow escapes through it. The other heads on the zone lose pressure, rise only partway and cover less ground. If the zone looks weak everywhere and you find a geyser, fixing the geyser usually brings the rest of the zone back.

What to Do Right Away

1. Turn off the zone at the controller. Skip it in the program until it is fixed.
2. Mark the head with a flag so you can find it easily.
3. Check the rest of the zone for other broken heads.
4. Fix it before your next watering day if you can.

Fort Worth’s watering rules count broken heads and runoff as water waste. A geyser sending water into the street is exactly the kind of problem the rules target. Our article on avoiding water waste violations covers the rules in more detail.

Replacing a Head Step by Step

1. Turn off the zone or the irrigation water supply.
2. Dig a hole around the head large enough to see the fitting below.
3. Unscrew the old head from the fitting or riser.
4. Keep dirt out of the open fitting.
5. Briefly run the zone to flush debris from the line, then turn it off.
6. Screw on the new head, set at the same height as the soil surface.
7. Install the nozzle and backfill, packing soil firmly around the body.
8. Run the zone and adjust the spray direction.

Our guide on sprinkler head repair covers other head problems you may find along the way.

Preventing Geysers

• Keep heads at the correct height so mowers do not hit them.
• Install swing pipe for heads near driveways and curbs.
• Consider relocating heads that keep getting hit.
• Drain or protect exposed parts before hard freezes.
• Do a yearly zone-by-zone check.

Geysers That Keep Coming Back

If the same head keeps breaking, the location is usually the problem. A head right at the edge of the driveway gets run over. A head beside a walk gets stepped on and kicked. A head in a spot where mowers turn gets clipped. Moving the head a short distance back from the edge, lowering it slightly with a swing pipe connection so it sits flush, or switching to a sturdier model can end the cycle. Sometimes a narrow strip along a drive is better served by a strip nozzle placed farther from the traffic.

When to Call a Technician

If the geyser comes from below the head, if several heads are broken, or if the break is near a driveway or walk, our sprinkler repair team can find the source and fix it.