Low water pressure in sprinklers is an inconvenience we can do without. You’ve probably experienced this at least once in your life and had no idea how to fix it.

Low Water Pressure in Sprinklers

Let’s explore all the possible causes of low water pressure and how to solve them.

What Are The Reasons For Sprinklers to have Low Water Pressure Issues?

The reason sprinklers have low water pressure issues is due to a weak source of water, or the water supply’s valve requiring adjustment. It’s also due to having partially open backflow in the preventer valve, shared water pressure, dirty irrigation filter, clogged sprinkler head and valve, or damaged underground pipes.

You might be watering your garden one day and suddenly the water supply becomes erratic, slow, or even gone. There are many reasons why this is happening, so we’ll need to be more discerning when looking for the reasons why the water suddenly lost its pressure.

– Weak Source of Water

Usually, our irrigation system gets its water from three sources: these are the city’s potable water supply, the city’s irrigation or reclaimed water, or an on-site water supply. While it might be tempting to immediately check your sprinkler system, looking into the water source first is best. As a result, the pressure would be coming in a slower manner than it should be.

– Water Supply’s Valve Requires Adjustment

Another common reason for the water pressure loss is when the water supply valve is partially closed. When the valve is partially closed, water cannot flow at the desired rate.

The restricted water movement also results in a drop in pressure, and you would check and see that notion from your end is going wrong, but again, the valve is the one in the wrong position, and requires an adjustment, because the supply of water through the sprinklers are coming very weakly.

– Partially Open Backflow Preventer Valve

Sometimes, the cause for the low pressure could be this valve. This will be evident when the pressure is fine inside the house, but the pressure isn’t enough when it comes to the sprinkler system. You’ll also notice that the valve is partially open when the handle sits on an odd angle, instead of a full 90 or 180 degrees.

– Shared Water Pressure

A shared water line is one of the most common reasons why your water suddenly loses its pressure. This usually happens because there is more than one water outlet running at the same time along with your irrigation or sprinkler system.

Reasons For Sprinklers to have Low Water Pressure

For example, if you are washing your car and using the sprinkler system at the same time, both activities will experience low pressure.

– Dirty Irrigation Filter

The filter works by screening off any large residues or contaminants in the water. Filters are often required in many modern water systems, so removing them is out of the question, and when there is dirt being filled on the other side, you will see that the pressure of the water is quite low.

When the filter becomes clogged with these impurities, you can experience low pressure coming from your water source.

– Clogged Sprinkler Heads and Valves

Take a look at the sprinkler heads around your irrigation system. If some have low pressure, these heads might be clogged with dirt or debris, or even sometimes minerals from the water can be stuck. A dirty sprinkler indicates that debris has gotten into the system’s parts and blocked the jet.

– Damaged Underground Pipes

The underground pipes are sometimes prone to damage, resulting in cracks or splits. The reason can be the material, the settling soil, frost, movements from heavy lawn equipment, or just age. This can cause a dramatic drop in pressure.

How to Fix Your Sprinkler System’s Low Water Pressure

To fix your sprinkler system’s low water pressure, you must check the water supply valve, and open the backflow preventer valve.

Also, stop sharing the water pressure, and clean the filters of the sprinkler and the clogged filter head. Check the damaged underground pipes, and contact the water supplier.

– Check the Water Supply Valve

If you suspect the cause for your low water supply is due to a partially open water supply valve, you’ll need to examine it the full way and check the damages. Simply look at the valve to determine that it is fully switched on. Most of the time, a partially closed valve with have a handle at an odd angle, and this is what must be adjusted.

If the handle is circular, then you can turn it until the pressure of the water gets stronger. The handle can be turned right or left depending on the setup to open the flow fully. Once you have full pressure, inform the other household members not to adjust the valve without consulting with you first.

– Open the Valve for the Backflow Preventer

Just like the water’s main supply valve, the backflow preventer valve needs to be checked if the pressure gets low. To do this, take a look at the valve to see if it has been accidentally adjusted, try to fix it, and relocate it in the right position.

You must keep in mind that the backflow preventer has two pipes: one is horizontal, and the other is vertical. Usually, there is a valve on each pipe, and each is responsible for different things, and depending on the setup and the handle, adjust the valves accordingly. Doing so will help you determine the right direction to open up the valve and allow full pressure for the water.

– Stop Sharing Water Pressure

If you suspect that the cause of your low pressure is shared water use, then you’ll need to stop it as soon as you can. For example, you can always schedule water use so that the pressure sprinkler system’s experience will be stronger, and the result will be great too because now the water will disperse throughout the whole lawn.

Fix Sprinkler Systems Low Water Pressure

Let’s say that you have a timed activity for your lawn sprinkler system. Avoid using the water for other activities, such as washing the car, while using your lawn irrigation system. If you have an automatic lawn sprinkler system, you can set it in the early morning, late at night, or at times when you don’t actively use your water supply.

– Clean Your Sprinkler Filter

When the reason for low pressure from your water line is a clogged filter, you can easily clean it with some vinegar and water solution to remove the clogged dirt, or you can simply replace it. To clean a dirty irrigation filer, pull it out of its housing. Inspect the filter for any damage; if there are clear signs of damage, discard it and replace it with a new one.

– Clean Your Clogged Sprinkler Head

A clogged sprinkler head has dirt and other debris in it, causing the gaps in the nozzle to close and the water to trickle out slowly. Check the heads by removing the top of the head. Inspect the internal filters and clean them as necessary, and you should manage to see the issue and fix it.

For the valves, remove the cover and inspect for dirt inside, and if it is dirty, then clean it. To avoid getting a dirty sprinkler head from build-up, it is best to check your sprinkler system regularly.

– Check for Damaged Underground Pipes

This is the hardest one to perform since it requires extensive work. If you are unsure about this undertaking, always consult a professional; however, you can do this yourself if you are confident about your skills.

Start by exposing the pipe, cutting off the broken section, and preparing the new pipe parts. Once all the components are ready, glue and install the couplings and cut the new pipe parts to length.

When the new pipe is ready, glue it and connect it to the undamaged pipe. Finally, backfill the hole and check your water pressure.

– Contact Your Water Supplier

If you have determined that the cause of your low water pressure is due to your supplier, you’ll need to contact them immediately. They may have maintenance issues that you were not aware of.

On the other hand, they may have issues with their water that they wouldn’t have known unless you contacted them, and the supplier would look into the matter and adjust it accordingly.

Stop Sharing Water Pressure on Sprinkle


Having low water pressure can be frustrating. Now that you know what to look for and how to fix them, you’re in a better position to deal with low sprinkler pressure and problematic sprinkler systems. Here are some quick reminders:

  • To reduce possible costs, always check the different options, such as the adjustment of the valve or the dirt that could be clogged in your sprinkler system.
  • Keep a preventative maintenance schedule for your sprinkler system, to avoid low pressure reaching them.
  • As much as possible, keep each sprinkler head clean to prevent the possibility of having a dirty sprinkler.

We know you can diagnose and treat low water pressure coming from any sprinkler head. Now, you can have great pressure in your sprinklers and watch them spread water evenly and in a stronger matter, and you will have a great green lawn. Also, make sure that you are using high-quality sprinklers since low-quality ones can easily and quickly fail you.

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