Common Causes of Low Sprinkler Water Pressure and How to Fix Them in Rockwall, TX

In Rockwall, TX, a dependable sprinkler system is essential for keeping lawns green and landscapes healthy through hot summers and changing weather. One of the most common issues that disrupts irrigation systems is low water pressure, which causes weak spray, uneven coverage, and dry spots in the yard. If left unresolved, low pressure can waste water and harm your lawn.

Andy’s Sprinkler, Drainage, & Lighting proudly serves Rockwall homeowners while also offering professional sprinkler repair in Carrollton, Southlake, Austin, and Lubbock. Our team of licensed experts knows how to diagnose and fix water pressure problems so your irrigation system runs efficiently all year long.

In this post, we’ll discuss some of the common reasons for low pressure sprinklers.

How Water Pressure Works in Sprinkler Systems

Water pressure is measured in PSI (pounds per square inch). Spray heads usually require 15–30 PSI to operate correctly, while rotor heads need around 30–50 PSI. Drip irrigation systems often function at 10–25 PSI.

In Rockwall, where the summers are hot and dry and soil can be clay-heavy, proper PSI is essential for coverage. Too little pressure leaves dry patches, while too much pressure can waste water and cause misting. Adequate pressure ensures your yard gets even watering through every zone.

Table of Contents

Causes of Low Sprinkler Pressure
Troubleshooting Low Pressure
Fixes and Upgrades
Preventive Maintenance

Backflow Preventer Valve Issue

One of the leading reasons for low sprinkler water pressure relates to the valves on your backflow preventer device. If you notice limited water pressure in your sprinkler system but normal water pressure inside your home, then the problem might be that your backflow preventer valves are not completely open.

If this is the only issue, the fix is simple: access your backflow valves and open them completely to improve your water pressure. Most backflow preventer devices have two pipes: one that is horizontal and one that is vertical. Since there is typically a valve on both pipes, we’ll make sure that all valves are fully open.

The valves are open once they are parallel to the pipe. We make sure to make adjustments to the horizontal pipe first before moving onto the vertical pipe. To ensure that this is done correctly and that it is the only cause for concern with your sprinklers, it is best to have a professional handle this process.

Water Line Leak or Break

A much more concerning problem involves a break or leak in your water line. This issue is typically caused by digging too close to a water line, then accidentally breaking it.

In Rockwall, water line damage can also happen due to shifting soil after heavy rains or drought periods. Signs of a leak include depressions in your lawn, unusual wet spots, or bubbling water near sprinkler zones. If you notice multiple heads in a row not working, that may point to a break as well.

To ensure the problem is detected and fixed properly, it’s highly recommended that you call the professionals at Andy’s Sprinkler to handle the whole process.

Shut-Off or Main Water Valves Aren’t Fully Open

Other valves you have to keep in mind include the shut-off valve and main water valve. Sprinkler systems typically have a shut-off valve that connects to your home’s water supply. To ensure adequate water pressure, be sure that this valve is opened all the way.

You’ll also want to keep in mind your main water valve, which is the valve that provides water for your entire home. To ensure proper water pressure, make sure that this valve is completely open as well. To help find these valves and ensure they are fully open, contact a professional for assistance.

Clogged or Dirty Sprinkler Heads

Sometimes sprinklers may indicate that there is a water pressure problem, but sometimes the issue lies within the sprinkler head. When sprinkler heads are clogged or dirty, then water is unable to flow properly through the system.

In Rockwall, dust and lawn debris can easily clog sprinkler heads, especially during windy, dry days. If this is the culprit, you’ll typically notice some sprinkler heads that are flowing properly and others that aren’t. In this case, you’ll need to have the sprinkler heads thoroughly cleaned and inspected for other issues.

Water Line Obstruction

Another common culprit of low water pressure involves what’s happening underground. If you have trees or large shrubs in your yard or nearby, then their root systems can infiltrate your water lines.

In Rockwall neighborhoods with mature oaks and maples, root intrusion is a frequent issue. To find a solution to this problem, it is highly recommended that you call a reputable service provider.

Other Common Causes of Low Sprinkler Pressure

Beyond the main culprits, other issues may include:
• Too many sprinkler heads per zone, creating overload.
• Aging or undersized pipes leading to friction loss.
• Municipal water pressure drops during peak summer use.
• Zone valve timer malfunctions.
• Whole-home filtration or softeners restricting flow.

How to Test for Low Water Pressure

Here are some quick DIY checks you can try before calling a pro:
• Attach a pressure gauge to your outdoor faucet (15–30 PSI for sprays, 30–50 PSI for rotors).
• Watch your water meter for unexpected movement, which may signal a leak.
• Do a bucket test by timing how long it takes to fill a gallon container.
• Compare spray coverage against manufacturer spacing guidelines.

Fixes and Upgrades

Solutions may be simple or involve upgrades:
• Clean or replace clogged nozzles.
• Repair small leaks quickly.
• Split overloaded zones.
• Install a booster pump if city water pressure is consistently low.
• Upgrade undersized pipes in older Rockwall homes.
• Switch to water-efficient rotary or low-flow nozzles.

Preventive Maintenance Tips

To prevent future water pressure issues:
• Flush the sprinkler system at least once a season.
• Clean heads and filters regularly.
• Inspect valves and lines yearly.
• Winterize before Rockwall’s occasional cold snaps.
• Consider smart irrigation controllers for efficient watering.

Choose Andy’s Sprinkler, Drainage, & Lighting Today!

If you’re dealing with any of the issues outlined above, then it’s time to pick up the phone and call Andy’s Sprinkler, Drainage, & Lighting, find out which location offers sprinkler repair near you. We offer top-notch sprinkler system services and we can ensure your yard is ready to look its best! Contact us today to schedule an appointment.