| CSLB #1045486 |

Safe Water Starts Here

Providing quality backflow services from Monterey to the Bay since 2016. AWWA & Cross - Connection Survey Certified.

Schedule a consultation for your property today!

Sergio Villegas & Alondra Haro | Founders 4th of July Backflow Testing LLC

Our Family, Serving Yours

We’re Sergio and Alondra, and we started 4th of July Backflow, LLC in 2016 to keep our community’s water safe while treating every customer like family. With my background in landscaping and a degree in Environmental and Occupational Health, I focus on backflow testing, repairs, and installations while Alondra manages the backend and ensures every customer feels supported. Together, we bring certified, reliable, and family-run care to every job.

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Experience . Trust . Local Care

Proudly Serving our Local Communities:

Monterey | San Benito | Santa Cruz | Santa Clara |
San Luis Obispo | San Mateo | San Francisco

8 + Years Field
Experience

Bringing 8 years of proven expertise in backflow services.

Family - Owned
& Operated

Caring for your backflow systems as if they were our own.

Licensed &
Certified

Rest easy knowing your service is in qualified hands.

Report? Consider It Done

We’ll submit your test result within 1–2 days after payment - so you don't have to.

5 Star
Reviews

Rated 5 stars for reliable and certified backflow testing.

What We Offer

Backflow Installations

Backflow Repairs & Replacement

Annual Backflow Tests

Cross - Connection Surveys

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We Serve:

Airports
Attractions
Condos
Hospitals

HOAs
Hotels
Malls
Military Bases

Private Residences
Restaurants
Schools
Shopping Centers

Theme Parks
Water Agencies
& More!

Learn more about our services and let us know what you need help with!

5 Star Rated for Quality and Care

Where quality service meets genuine customer care.

Richard Vargas

This company had great service and flexible scheduling. Affordable pricing rounded this out for a 5-stars! I would recommend them.

Amy Manuel

We've had excellent service on our backflow testing for the past seven years! Sergio is always friendly, professional, and efficient. He takes the time to explain any issues clearly, making the process smooth and stress-free. Highly recommend!

Dan Patel

Its has always been a pleasure working with Sergio, this is the 2nd job, Sergio as done in a very professional, timely and cost effective. Thank You for being there when needed fast.

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Got Questions About Backflow? We've Got Answers.

How Much Will My Backflow Test Cost?

Most backflow tests range from $120–$250. The price depends on your device’s location and your water company’s rules. Some require a compliance tag, which only certified testers are able to purchase, and that may add a small extra cost.

How Often Should I Test My Backflow Device?

Most water companies require annual testing, though some areas may require it every six months. You’ll receive a notice from your water provider when it’s time for your backflow test.

Why Do I Need a Backflow Installed?

Water companies require backflows for high-risk properties. If the water system loses pressure, water could flow backward and bring contaminants - like chemicals, well water, or irrigation water into your drinking water. Backflows are designed to protect the public water supply and ensure everyone has safe, clean water.