Slab Leak Repair Los Angeles: $630 to $4,400 + LADWP Credits

Slab leak and detection rows are national; no publisher prices slab leaks for Los Angeles alone. Angi's LA rows show local service call and repipe prices.

Do this now: if you think you have a slab leak in LA

1. Stay out of standing water near outlets, cords or appliances. The Red Cross says not to touch electrical equipment if it is wet or while you stand in water.
2. If water is coming up through the floor, shut off the main water valve.
3. Run the EPA meter test: read the water meter, use no water for two hours, then read it again. Any movement means a leak.
4. Water at the street, sidewalk or meter box instead? That is LADWP's side: call 1-800-DIAL-DWP (1-800-342-5397).
5. Photograph wet floors and walls and call your insurer before repairs start. Do not sign any contract that hands your claim to a contractor.

Is it urgent? When a slab leak cannot wait

A slab leak is urgent when water is coming up through the floor, because the EPA says wet materials should be dried within 24 to 48 hours to prevent mold. A warm spot on the floor or the sound of running water with every fixture off is a same-day call (HomeAdvisor lists both as signs). A water bill that jumped, or a meter that moves in the two-hour test, can usually wait a few days for leak detection.

Leak detection in Los Angeles: cost and how it is found

Leak detection costs $150 to $400 for most homeowners in HomeAdvisor's 2026 data, about $280, and Fixr's range is $100 to $400. Fixr says detection uses pressure testing, checks of the slab for cracks and moisture, and a look at landscaping for excess water, and that it can take minutes or over an hour. Finding the exact spot first means the floor is opened once, in the right place.

In Los Angeles, access is the expensive part. Angi's LA guide says slab foundations make plumbing access more labor intensive, and that galvanized piping in many neighborhoods is prone to corrosion and leaks. Ask the detection company to mark the leak and estimate whether a spot repair or a reroute makes more sense before anyone breaks concrete.

Spot repair, reroute or repipe: what LA's permits allow

Rerouting a leaking line out of the slab runs $4,000 to $15,000 in Fixr's figures, against $630 to $4,400 for most repairs in HomeAdvisor's data. A reroute often makes sense when one leak in old pipe is likely to be followed by more; Angi's LA guide puts repiping in Los Angeles at $1,500 to $5,000 or more, the same band as sewer replacement.

For the permit, LADBS lists replacing underground water pipes with the same size and material as an Express Permit, issued without plan check, and says the old pipe stays uncovered until the inspector verifies it. A licensed contractor is required: CSLB's minor work limit is $1,000, and it never covers work that needs a permit.

LADWP's leak credit: does a slab leak count?

LADWP may adjust your water bill after you repair an underground leak on your property, if you ask within 12 months and include repair receipts; allow two to four weeks. Leaks from sprinklers, water heaters, faucets or toilets do not qualify. LADWP's page does not say whether a leak under the slab counts as underground, so ask its customer service when you submit the receipts.

Hardness varies across the city. LADWP's 2022 monitoring tables show 103 mg/L from the Los Angeles Aqueduct Filtration Plant and 230 mg/L from the city's own wells, with MWD supply in Eastern LA and the Harbor area near 279 mg/L. Ask your plumber what your pipes are made of and how they have held up in your area.

City of Los Angeles rules, programs and contacts from official city, utility, state, Census and NOAA pages. Other LA County cities set their own permit rules.

What to ask an LA slab leak plumber

1. How will you find the leak, and what does detection cost if you also do the repair?
2. Spot repair or reroute: what does each cost, and which do you recommend for pipe this age?
3. Will you pull the LADBS permit and leave the old pipe uncovered for inspection?
4. Can you give me receipts LADWP will accept for a leak adjustment?
5. What is your CSLB license number, and can I see proof of insurance?

More help in Los Angeles

Water damage from the leak: water damage restoration in Los Angeles. All plumbing topics: plumber in Los Angeles. Water heater leaks: water heater repair in Los Angeles. National guide: slab leak repair cost. Other cities: slab leak repair in San Diego and slab leak repair in Phoenix. All trades: home repair costs. Calls go to an independent company that serves your area and takes this kind of job (how calls work).