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Pool Repair Brentwood

Brentwood, CA · East Contra Costa

Pool Leak Detection & Repair in Brentwood, CA

Topping off the pool more than usual? A leak wastes water, washes out chemicals, and can undermine the ground around the shell. Finding it is a job of testing, not guessing.

Repairs & equipment, not weekly cleaning · No obligation

Signs it's a leak, not the weather

  • You add water every few days

    Even in mild weather, when evaporation is low.

  • The level drops faster with the pump on

    Points toward the pressure side: return lines or equipment.

  • It stops dropping at the same spot

    Often the height of a skimmer, a light, or a return fitting.

  • Wet spots, soggy lawn, or cracks

    Damp ground near the pool or the equipment pad, or new cracks in the deck or plaster.

First: is it really a leak?

Pools lose water to evaporation every day, and East County summers push that number up: hot afternoons, low humidity, and wind across the water. A common rule of thumb is about a quarter inch a day, more in a heat wave. The quick way to separate evaporation from a leak is the bucket test: a bucket of pool water on the step loses water to evaporation at the same rate as the pool, so any extra drop in the pool is a leak. Step-by-step instructions are in pool leak or evaporation?.

Turn off the auto-fill first

An automatic fill valve can hide a leak for months by quietly topping the pool back up. Shut it off before any test, and check your water bill for an unexplained jump.

Where pool leaks usually are

WhereCluesTypical fix
Skimmer throatLevel stops at the bottom of the skimmer opening; a crack where the skimmer meets the shellSeal or rebuild the skimmer joint
Light nicheLevel stops at the light; conduit or cord seal has failedReseal the conduit, replace the lens gasket, or repair the light
Return fittingsLoses more with the pump runningReplace fittings and gaskets
Underground plumbingLoses water with the pump on and off; wet ground between pool and padPressure-test lines, then repair or reroute the broken section
Main drainKeeps dropping below the lowest fittingRepair the drain body or pipe
Shell or plasterVisible cracks, hollow-sounding plaster, delaminationPatch the crack; widespread damage points to resurfacing
Equipment padDrips or puddles at the pump, filter, heater, or valvesReplace seals, O-rings, or unions (equipment repair)

How professional leak detection works

  • Measuring the loss with the pump on and off, which narrows it to the suction side, the pressure side, or the shell.
  • Dye testing at fittings, cracks, and the light niche. A diver or a pole puts a drop of dye near the suspected spot and watches whether it gets pulled in.
  • Pressure testing each plumbing line by capping it and watching whether it holds pressure.
  • Acoustic listening along underground lines to pinpoint a break before anything is dug up.

The goal is to open the deck in one place, not five. Ask the contractor which of these tests they'll use and what the price covers if they find the leak (detection only, or detection plus the repair).

What pool leak detection usually costs

HomeGuide puts professional leak detection at about $100–$1,000, with most inground pools landing around $400–$1,000, and typical leak repairs after that at about $500–$1,500 (HomeGuide, 2026). Underground plumbing that has to be dug up costs more. A small skimmer or fitting leak can cost far less.

National ranges, not a quote; Bay Area jobs often land in the upper half. Full breakdown: pool repair costs in Brentwood.

Why fixing it soon matters

A leak doesn't just cost water. Fresh fill water throws off the chemistry, and water escaping under the shell or deck can wash out soil, which leads to settling and cracks. A small leak found early is usually a fitting or a seal. The same leak left for a season can turn into plumbing and plaster work. If the leak is in the tile line or the plaster, see pool tile repair and pool resurfacing.

Check any contractor, including one you find here

  • Ask for the contractor's CSLB license number and look it up at cslb.ca.gov. Swimming pool contractors are generally licensed under the C-53 classification.
  • Get the quote in writing, with the parts and the make and model of any new equipment.
  • Don't pay large sums up front.
  • For gas or electrical work on a pool heater or light, make sure the person doing it is qualified for that work.

This site is a free referral service, not a contractor. Your request goes to an independent local pool contractor, who gives the quote and does the work. How this works

Pool Leak Detection: common questions

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Pool down, leaking, or won't heat?

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