Aloha, this is Shane from 535 Plumbing. My team and I have been working on plumbing systems all across Hawaiʻi for a long time, and every rainy season I hear the same question from homeowners: “Can all this rain really mess with my plumbing?”

The short answer is yes — heavy rain can absolutely cause plumbing backups, especially here in Hawaiʻi. We don’t deal with frozen pipes like the mainland, but our rainy season brings a different set of plumbing challenges that a lot of people don’t see coming until there’s a problem.

I want to walk you through why rainy season affects your plumbing, the warning signs to watch for, and what you can do now to prevent costly backups later.

Why Hawaiʻi’s Rainy Season Is Hard on Plumbing Systems

During the rainy season, the ground around your home becomes saturated with water. That might not sound like a big deal, but underground plumbing pipes rely on stable soil to stay supported. When that soil is soaked, it shifts and puts pressure on sewer and drain lines.

In newer homes with updated piping, this may not cause issues right away. But in older homes — which many of us live in across Oʻahu and the neighbor islands — the plumbing systems were not designed for decades of soil movement, heavy rain, and tree growth.

Rainy season doesn’t usually create plumbing problems from scratch. What it does is expose problems that were already there.

How Heavy Rain Can Lead to Plumbing Backups

Saturated Ground and Sewer Line Pressure

When the soil is full of water, it presses against your sewer line. If the pipe has cracks, weak joints, or corrosion, that pressure can cause it to shift or collapse. Even a small sag in the pipe can lead to slow drains or full backups.

This is something we see often during heavy rain — homeowners call us because everything was “working fine” before, but now multiple drains are backing up at once.

Stormwater Overwhelming Older Sewer Systems

Some older neighborhoods in Hawaiʻi have sewer systems that struggle during heavy rain. When stormwater overwhelms the system, the water has to go somewhere. If your home doesn’t have proper protection, it can push water back toward the house instead of away from it.

That’s when people experience sewage smells, bubbling toilets, or water coming up through floor drains or showers.

Tree Root Intrusion Gets Worse in Wet Weather

Tree roots are one of the biggest causes of sewer problems in Hawaiʻi. During the rainy season, roots grow faster and search for moisture. Sewer lines are an easy target.

Roots can push into tiny cracks in pipes and slowly grow until they block the line or cause it to break. This doesn’t happen overnight, but rainy season is when the damage becomes noticeable.

We often find major root intrusion during sewer camera inspections, especially in older areas with large trees.

Existing Clogs Become Bigger Problems

Grease, soap buildup, hair, and debris collect in drain lines over time. During dry months, water may still squeeze through. But when rainy season adds more pressure and water volume, those partial clogs can turn into full blockages.

That’s when sinks drain slowly, toilets back up, or multiple fixtures stop working at once.

Warning Signs Your Plumbing Is Struggling During Rainy Season

One of the best things you can do as a homeowner is pay attention to early warning signs. Catching a problem early can save you a lot of stress and money.

Here are signs we tell our customers to watch for:

• Slow drains throughout the house
• Gurgling sounds from toilets or sinks
• Bad smells coming from drains
• Water backing up in showers or tubs
• Toilets that bubble when other fixtures are used
• Patches of grass in the yard that are always wet or extra green
• Drains that work fine when it’s dry but act up after heavy rain

If you notice more than one of these, it’s usually not just a simple clog — it’s often a sewer or main drain issue.

A lot of people wait until something breaks to call a plumber. I get it — nobody wants to deal with plumbing issues if they don’t have to. But rainy season is actually the best time to inspect your system, because problems show themselves more clearly.

At 535 Plumbing, we use sewer camera inspections to look inside your pipes without digging. This allows us to see cracks, root intrusion, buildup, and pipe alignment issues before they cause a full backup.

We also offer leak detection services, which are especially helpful during rainy months when hidden leaks can be mistaken for stormwater problems.

Services We Recommend During Hawaiʻi’s Rainy Season

After years of working through Hawaiʻi s rainy season, there are specific plumbing services I consistently recommend to help homeowners prevent drain backups, sewer problems, and water damage. Heavy rain across areas like Honolulu, Kapolei, Pearl City, Aiea, Kāneʻohe, Mililani, North Shore, and the neighbor islands puts extra pressure on drain lines, sewer systems, and older pipes — especially in established neighborhoods.

Drain Cleaning Services

Professional drain cleaning is one of the most important services during Hawaiʻi’s rainy season. In many Hawaiʻi homes, grease, soap buildup, hair, and debris collect inside drain lines over time. When heavy rain hits, those partial clogs can quickly turn into full drain or sewer backups. Routine drain cleaning helps homeowners keep their plumbing flowing properly during periods of heavy rainfall.

Hydro Jetting from Homes with Tree Root Issues

Tree root intrusion is a common problem across Hawaiʻi, especially in older neighborhoods with large trees. Hydro jetting uses high-pressure water to clear heavy buildup and cut through roots inside sewer lines. This service is especially effective for homes in areas like Mānoa, Kailua, and older parts of Honolulu where root intrusion is a frequent cause of sewer backups.

Sewer Camera Inspections

If you’re dealing with slow drains, frequent backups, or sewer odors, a sewer camera inspection allows us to see exactly what’s happening inside your pipes. This service is ideal for homes with aging sewer lines, allowing us to identify cracks, root intrusion, and pipe misalignment without digging. Rainy season is one of the best times for sewer inspections because existing problems become more noticeable.

Pipe Repair and Replacement, Including NuFlow Trenchless Pipe Lining

For damaged or corroded pipes, repair or replacement may be necessary. We offer NuFlow trenchless pipe lining throughout the islands, which allows us to repair pipes from the inside with minimal digging. This is a great solution for homes, townhomes, and properties where preserving landscaping, driveways, or concrete is important.

Above-Ground and Underground Leak Detection

We provide both above-ground and underground leak detection services. Hidden leaks are common during rainy season and can be mistaken for drainage or stormwater issues. Accurate leak detection helps prevent water damage, high water bills, and soil erosion around plumbing lines.

Backflow Testing, Installation, and Memberships

Heavy rain can overwhelm sewer systems in some Hawaiʻi neighborhoods and cause water to flow backward into homes. Backflow testing ensures your plumbing system is protected, and installing a backflow preventer can help stop sewage or stormwater from entering your home. We also offer Backflow Testing Memberships to make annual testing easy and stress-free.

Aloha Membership Preventive Plumbing Maintenance

Our Aloha Membership is designed for homeowners who want year-round peace of mind. It includes routine plumbing inspections and maintenance that help catch issues early — before rainy season turns them into emergencies. Preventive care is one of the best ways to avoid unexpected plumbing repairs

Why Local Experience Matters

Plumbing in Hawaiʻi is different from plumbing on the mainland. Our soil, weather, tree growth, and older infrastructure create unique challenges. That’s why working with a local plumbing company that understands Hawaiʻi conditions makes a big difference.

At 535 Plumbing, we’ve helped homeowners across the islands deal with rainy-season plumbing issues for years. We don’t believe in scare tactics — we believe in honest inspections, clear explanations, and solutions that make sense for your home and budget.

Final Thoughts

Rainy season in Hawaiʻi doesn’t have to mean plumbing problems — but ignoring warning signs can turn a small issue into a major mess. If your drains aren’t flowing right, if you notice changes after heavy rain, or if you just want peace of mind, it’s better to check things out early.

If you have questions or need help, give us a call at 535 Plumbing. We’re here to help keep your home safe, dry, and flowing smoothly — no matter how hard it rains.

Mahalo for trusting local.

Start the new year with confidence. Call (808) 300-0535 to schedule your end-of-year plumbing inspection today. Hiring a licensed plumber ensures the job is done correctly and up to code.

Call 535 Plumbing for Expert Advice

Whether you choose to repair or remodel, 535 Plumbing can help you make the right decision for your home and budget. We provide honest recommendations, professional installation, and access to high-quality appliances designed for island life.

📞 Call us today at (808) 300-0535 to schedule your consultation.

Want Peace of Mind All Year?

Join one of our 535 Plumbing Membership Plans and get:

• 1 Free Annual Plumbing Visual Inspection
• 1 Free Water Heater Flush Per Year
• Priority Scheduling & Special Discounts
• Ongoing System Monitoring & Maintenance Tips
• Annual Backflow Inspection and Test

Let us help you prepare, protect, and prevent plumbing problems—before and after the storm.

Get a Professional Quote for Your Plumbing Emergency

535 Plumbing specializes in plumbing inspections and repairs. Whether you need a routine cleaning or a complex repair, we provide expert plumbing services tailored to your specific situation. Contact us today for a professional assessment and a customized quote to keep your plumbing system in top shape!

Contact 535 Plumbing today to schedule an inspection and take the first step toward reclaiming control over your building’s plumbing. We have the tools and expertise to diagnose and resolve your issue efficiently. Don’t let a simple plumbing problem escalate—take action today to maintain the functionality of your building’s plumbing system. For more plumbing maintenance tips and advice, check out our other guides!

Contact 535 Plumbing Today

535 Plumbing is here to help. We offer:

• Fast and Reliable Service: Get prompt assistance when you need it most.
• Expert Technicians: Our skilled plumbers have experience with all garbage disposal types and plumbing systems.
• Upfront Pricing: No surprises—just honest, transparent estimates.
• Sustainable Solutions: We fix garbage disposals efficiently to save water and reduce your environmental footprint.

If you live on Oahu and are in need of a licensed plumber to help with your plumbing issues, choose 535 Plumbing for the job! Our team of professional Oahu plumbers are highly skilled and our excellent customer support representatives will work with you to schedule your appointments at a time you most convenient. Learn more and schedule an appointment by calling (808) 300-0535, or Visit Our Contact Us Page. Mahalo!