Leak detection and slab leak repair in San Diego

How can you tell whether you have a hidden leak?

The City of San Diego describes a simple meter test anyone can do:

1. Turn off all faucets and water-using appliances so no water is being used.
2. Note the position of the dial on your water meter and wait 30 minutes.
3. If the dial has not moved, the city says your home is relatively water-tight.
4. If it moved, check hose connections, faucets, toilets and appliances with water lines, such as dishwashers, washing machines, water heaters and refrigerators.
5. If everything is off, nothing visible is leaking and the dial still turns, there may be a concealed leak in an underground pipe, and a plumbing professional may be needed for leak detection.

The city says the meter is usually near the curb in a concrete box marked "water." It also notes that billing uses HCF, 100 cubic feet or 748.5 gallons, which helps when comparing your bill with what you think you use. Our guide on why San Diego water bills spike goes further.

What are the signs of a slab leak?

Many San Diego homes sit on concrete slabs with supply pipes underneath. HomeAdvisor lists these common signs of a slab leak:

• Warm or damp spots on the floor
• Standing water
• Sudden changes in water pressure
• Unusually high water bills
• The sound of running water when no fixtures are in use

What does leak detection and slab leak repair cost?

These are national figures from HomeAdvisor's slab leak repair guide, updated June 2026.

For an ordinary accessible leak, HomeGuide's plumber cost guide puts the cost to fix a leak at $150 to $850.

How does professional leak detection work?

A leak detection visit usually starts by confirming that water is being lost, often by isolating sections of the system and watching the meter or a pressure gauge. The technician then narrows down the location, for example by listening for the sound of escaping water or by checking for temperature differences in the floor where a hot water line runs. The goal is to open as little floor, wall or yard as possible. Ask before the visit what methods will be used, whether the price includes a written report, and whether repair is quoted separately.

Once the leak is found, the main options are a spot repair through the slab, rerouting the line through walls or the attic, or lining the pipe. A reroute abandons the leaking section rather than breaking the floor. Ask each contractor which option they recommend and why, in writing.

Who is responsible: you or the water utility?

For City of San Diego customers, the city maintains the main, the service line and the meter, and a city crew repairs leaks on its side. Everything on the property side of the meter is the owner's to repair. Signs of a meter leak include standing water in the meter box, soil that stays saturated and water flowing from the meter. Report those on the water emergency line at 619-515-3525. Outside the city, check with your own water agency.

Which permits and licenses apply?

The City of San Diego lists water or sewer piping repairs as work that needs a plumbing permit, with no exemptions. That means California's minor work exemption for unlicensed handypersons does not cover a slab leak repair, since the exemption only applies to work needing no permit. Check any contractor in the CSLB license lookup and get the repair method, footage and any wall or floor patching in the written contract. If you have water damage, photograph it before any work starts for your insurer.

For active, spreading water, close the main shutoff first and use our emergency checklist.

We are an independent guide and do not do plumbing work. You can send a request through our contact page; we reply with next steps and, where we know a licensed contractor for your area, an introduction.