Summary:

• San Mateo’s climate is changing. Heavy rainstorms are increasingly common, and our infrastructure isn’t equipped to keep up after years of droughts. 
• Record-breaking rainfall in 2024 from multiple storms caused billions of dollars of damage across California. Storms like these aren’t going away any time soon.
• Aging infrastructure, corrosion from dry conditions, urbanization, and poor maintenance can be a perfect storm for your pipes. They make it harder for local drainage systems to keep up during torrential downpours.
• You can’t control the weather, but you can take practical steps to reduce your risk for storm-related plumbing emergencies—like installing a backflow preventer or sump pump.
• Scheduling a yearly inspection can also help you notice problems before failures occur.

Here in San Mateo, it’s fair to say most people are used to droughts. California’s dry cycles come and go, but they tend to last for months or years at a time.

Droughts strain the local water supply and lead to heavy restrictions on use, but being unable to water your garden isn’t the only issue. Years-long dry conditions also wreak havoc on your plumbing, making pipes and aging infrastructure more prone to corrosion and cracking.

With climate change bringing sudden heavy rainstorms back to the region, damaged pipes can be a serious problem. A rush of stormwater can lead to flooded streets, backed-up drains, and costly property damage if your system is already compromised.

Don’t wait for the next storm to expose the cracks in your system. Send us a message at Caccia Plumbing to learn how we can help!

Related: What To Do During a Plumbing Emergency

How Caccia Plumbing Can Help You Prepare for Rainstorms

At Caccia Plumbing, we’re proud to help residents of San Mateo prepare for storms and respond to plumbing emergencies when they strike. Whatever the weather brings, we’re always standing by.

We can help with:

• Emergency plumbing to address problems like failures, floods, and leaks—even if they happen during a storm, outside of working hours, or on a holiday.
• Sump pump installation and repairs that help keep your basement flood-free during severe storms, or just when your old water heater decides to give up.
• Backflow preventers that help protect your home from contaminated wastewater if it overwhelms the local water supply during storms.
• Regular maintenance and inspections to help discover potential problems with your plumbing so your pipes and drainage systems remain free and clear.

Our licensed and insured plumbers have the knowledge and skills needed to protect homes from severe weather systems in San Mateo and the surrounding communities. Read on to learn more about preparing for rainstorms, then call us for help.

Related: How to Recognize Sewer Leaks

The Impact of California’s Rainstorms

Heavy rainstorms in California caused billions of dollars in damage in 2024 alone. According to the Department of Water Resources, over 9.4 inches of rain fell between January and December—that’s nearly 15% higher than the year before.

Last year’s most serious events included at least three atmospheric river storms and a rare tornado that touched down near Santa Cruz, tossing vehicles off the road. Here’s how some of these incidents affected plumbing and electrical services:

• February 2024. In early February, a string of atmospheric river storms occurred over Los Angeles, San Francisco, and the central coastline. Record-breaking rainfall triggered flash floods and overloaded local drainage systems, causing over 8 million gallons of sewage to spill onto the street.
• November 2024. In November, another atmospheric river event took place over the Bay Area and northern California. Heavy bands of precipitation dumped between one and four inches of rain on the Bay Area over a three-day period. Aging drainage and sewer systems struggled to keep up, causing water to back up into homes.
• December 2024. In December, a powerful level 3 storm pounded the Bay Area with torrential rain. The storm was severe enough to cause widespread power outages, flooding, and an F1 tornado that touched down briefly in Santa Cruz. It was quickly followed by a series of smaller storms affecting the Bay Area over the holidays.

California’s storms are expected to grow more intense over the coming decade, pushing a system that’s clearly already strained to the limit. But extreme weather isn’t the only challenge—years of drought have made pipes even more vulnerable to damage over time.

Why California’s Pipes are Struggling So Much

Why are residential plumbing systems breaking down during storms after years of drought conditions? The short answer is that too little water moving through your system is as big a problem as too much.

The same measures you take to reduce your consumption during a dry spell can leave your pipes vulnerable to damage during rainstorms and floods. Here’s how:

• Pipes can corrode over time from not carrying enough wastewater during extended dry spells. They may crack or burst without warning during or after a storm.
• Decades-old sewer systems were never designed to handle the kind of rainfall triggered by climate change. Storms can quickly overwhelm drainage points.
• Aging pipes and connections in older homes pose a problem for the same reason—they’re already prone to problems and often struggle to keep up.
• Urban sprawl makes city and town water systems more vulnerable to failures over time. Every new addition or connection increases the burden on outdated systems.
• Poor maintenance practices at home can lead to clogs and blockages, triggering severe leaks, water damage, or sewage backups.

You might not be able to control mother nature, but you do have the power to ensure your plumbing is up to the task before storms strike. Taking action now could help you avoid problems that cost you thousands of dollars to fix after the fact.

Related: How to Find Your Water Shut-Off Valve

Common Problems Caused by Overwhelmed Pipes

We’ve already talked about the factors that lead to pipes becoming overwhelmed in the first place. Now, let’s take a closer look at how this causes problems for homeowners.

If your plumbing system isn’t ready for the next storm, you might experience:

• Flooding in your street, front yard, or home. When water has nowhere to go, it can pool up quickly, leading to serious structural damage and expensive repairs.
• Sewage backups. Trapped wastewater with nowhere to go will look for the closest point of escape—and that might include your toilets and floor drains.
• Erosion and damage to underground pipes. High volumes of water increase pressure on pipes, leading to sudden cracks and floods.

No homeowner looks forward to plumbing emergencies like these. Unfortunately, it’s all too common for regular maintenance to be an afterthought until it’s too late. Take the steps in the next section to lower your risk for problems during and after storms!

Solutions to Improve Pipe Infrastructure

California’s aging infrastructure can’t be overhauled overnight, and the effects of climate change can be extremely unpredictable. But that doesn’t mean homeowners and local governments can’t start working together on short and long-term solutions right now.

Short-Term Solutions (What You Can Do At Home)

• Make regular maintenance a priority. Schedule a sewer and plumbing inspection at least once per year. If you have underground pipes, let us know—we have special Ground-Penetrating Radar (GPR) equipment that helps us spot corrosion or leaks.
• Install a sump pump in your basement or crawlspace. Sump pumps kick in automatically when they detect water and pump it out before it can cause a flood, even if you aren’t home at the time. 
• Add a backflow preventer to your sewer line. This is a simple and effective device that stops waste from re-entering your home when the system is overloaded. Regular backflow testing ensures that this system is working properly.

Long-Term Solutions (How Cities Can Improve Infrastructure)

The City of San Mateo is already taking action to improve stormwater management in a number of ways, but changes like these take time. While you’re waiting for them to go into effect, make sure the plumbing on your property is protected.

• Expanding municipal sewer capacity. Upgrading local systems with larger-capacity storm-resistant pipes can help lower the risk for flooding and overflows during storms.
• Installing green infrastructure. Rain gardens, tree stands, and other green spaces help absorb stormwater naturally from the ground, reducing the burden on sewers.
• Rolling out flood prevention measures. Permeable pavement allows water to pass through walkways and roads so it doesn’t pool up, while retention basins channel it away into ponds that can sometimes be cultivated into an attractive water feature.

Want to know more about what the government is doing to address stormwater risks and improve drainage? Visit the City of San Mateo or San Mateo County Sustainability Department online.

Related: Why You Need a Basement Sump Pump

Stay Ahead of Storms With Caccia Plumbing

Proactive maintenance and infrastructure upgrades make it easier for California residents to sit out heavy rainstorms without facing serious structural damage or costly repairs. As climate change continues to intensify the systems that move through our region, it will become more important to do everything you can to stay one step ahead.

Take the first step toward peace of mind during rainstorms with the experts at Caccia Plumbing by your side. Contact us here or call (650) 442-1470 to protect your property and drainage system from rainstorms, no matter what the future brings!

Frequently Asked Questions About Stormwater, Your Plumbing, and Preventing Storm Damage

When should I call a plumber after a storm?

Contact us whenever you need help or advice about your residential plumbing, no matter how big or small the job. If you’re looking for help after a storm, you can send us a message or reach us by phone for faster help. 

We can help with:

• Slow drains
• Sewer backups
• Low water pressure
• Flooding in your yard or house
• Water damage and/or leaks
• Broken, cracked, or burst pipes

If you aren’t sure whether you need a plumber, give us a call anyway. We’re always happy to listen and recommend the right path forward.

How does rain lead to sewage backups in the home?

The technical term for this is hydraulic overload, but here’s a simpler way to understand it. Think of a bathtub with two drains, one for normal water flow and another for emergency overflow. 

Under typical conditions, water flows smoothly down the main drain. If the tub starts to fill too quickly, the overflow should kick in and redirect the extra water.

But what happens if the overflow is blocked and you suddenly turn on multiple faucets at full blast? The water has nowhere to go, so it will eventually spill over the sides.

San Mateo has a separated sewer and stormwater system, but intensely heavy rain can still overwhelm drainage lines and cause water to pool up. That overflow can eventually seep into cracks in the sewer line—or even flood into your home.

Backflow testing can help detect wastewater from reversing reverse direction or entering your clean water supply. If we find a problem, installing a backflow preventer can help.

Will my sump pump still kick in if the power goes out?

Maybe. If your unit has a battery backup, you install a water-powered backup system, or you have a generator that kicks in automatically when the power goes out, your sump pump should continue operating normally. 

Sump pumps that don’t have access to a power source or backup system often go down during severe storms and power outages. We don’t recommend running units like these alone without support. Ask us how we can help you upgrade to a more reliable option!

Should I turn off my water during a severe storm?

In general, no—it isn’t necessary as long as your plumbing is well-maintained and in good shape, but there are a few exceptions. If flooding occurs inside your home, a pipe bursts, or sewage begins to back up, you should turn off the water and call for help right away.

You should also be mindful of electrical hazards during a flood. If water reaches outlets, power strips, or appliances that are still plugged in, it can cause short circuits or even pose an electrocution risk. If you can get to your electrical panel safely, turn off the main breaker. Then, exit the building and give us a call for help.

We also recommend having your boiler inspected and serviced at least once per year (twice if you have an older, less efficient system). This will help ensure it stays in good working condition with no sudden surprises.