Can a Plumber Replace My City-Required Water Service Line?

The Problem With Searching "Plumber"

When a city sends a homeowner a notice about a water service line, the natural instinct is to search for a plumber. After all, water lines sound like plumbing. But in California, the type of license a contractor needs depends on where the work takes place — not just what the work involves.

A water service line runs from the city's water main (in the street or parkway) to your water meter. That portion of the line crosses the public right-of-way — the strip of land owned by the city between your property line and the street. Any construction work in the public right-of-way requires a CSLB Class A General Engineering license.

The License That Matters

Plumbers in California typically hold a C-36 Plumbing Contractor license. This license qualifies them for plumbing work inside buildings and on private property. It does not qualify them for infrastructure work in the public right-of-way. Hiring a C-36 contractor for city-required water service line work can result in failed inspections, stop-work orders, and having to redo the work at your expense.

What Is a Class A General Engineering License?

A CSLB Class A General Engineering Contractor license is required for projects that are "fixed works" requiring specialized engineering knowledge and skill — including pipelines, utilities, water lines, sewer lines, and other infrastructure that crosses or sits in the public right-of-way.

Class A contractors are the category of contractor that cities and counties require for encroachment permit work — the formal permit required any time a contractor works in the public right-of-way. Without a Class A license, a contractor cannot legally pull an encroachment permit for water service line work.

Why Cities Are Sending These Notices

Across Los Angeles and Orange County, cities are actively identifying and requiring replacement of aging water service lines — particularly older galvanized steel or lead service lines that are deteriorating or no longer meet current standards. Cities including Anaheim, Fullerton, Buena Park, Huntington Beach, Norwalk, Downey, and Cerritos have active programs that generate these notices.

In some cases, the notice is triggered by a building permit application (for an ADU, addition, or remodel) that requires the water service to be upgraded to current standards. In other cases, the city proactively identifies aging infrastructure and issues notices directly to property owners.

What to Look for in a Contractor

When hiring a contractor for city-required water service line work, verify the following before signing anything:

CSLB Class A General Engineering License — Verify at cslb.ca.gov. This is the license required for right-of-way work.
Encroachment Permit Experience — Ask if they pull their own encroachment permits. A qualified contractor will handle this directly with your city or LA County Public Works.
Current Bonding and Insurance — City-required work in the public right-of-way requires specific bonding and insurance levels. Ask for certificates.
Experience With Your Specific City — Each city has its own permit process, inspection requirements, and approved materials. Experience with your city matters.

About Ambros Construction

Ambros Construction Inc. holds a CSLB Class A General Engineering License (#1037467), a C-34 Pipeline License, and a Class B General Building License. We are based in Norwalk and serve homeowners across Los Angeles and Orange County for exactly this type of city-required right-of-way work.

We handle the encroachment permit application, coordinate directly with your city's Public Works department, complete the water service line work, and manage the final inspection — so your notice gets closed and you don't have to navigate the process alone.