Published 2025-03-18  |  Placentia Leak Repair Experts

Your Placentia Pool Loses More Water in July Than December: Here Is What Is a Leak and What Is the Heat

Placentia pool owners notice it every summer: the water level drops faster in July and August than it did in May, even though no one is splashing more or filling more frequently. The pool looks the same. The equipment is running normally. But you are adding water more often than you did in spring.

This is not always a leak. Placentia's inland North Orange County location produces summer high temperatures that regularly exceed 90 degrees, and July sun angle and duration drive evaporation rates substantially higher than December. A pool that loses a quarter inch per day in winter may lose significantly more per day in peak summer conditions without any structural or plumbing failure being present. But the bucket test is the only way to know for certain which situation you are in.

Summer Evaporation in North OC

Evaporation rate from a pool surface depends on air temperature, relative humidity, wind speed, and direct sun exposure. Placentia in July has all the conditions that maximize evaporation: high air temperature, low relative humidity for an inland location, afternoon sea breeze that carries evaporated moisture away from the pool surface, and long daylight hours with direct sun exposure on an outdoor pool. These conditions can produce daily water level drops that alarm homeowners who are used to the winter rate.

The bucket test removes the guesswork by measuring evaporation and leak loss simultaneously with the same weather conditions. If the pool loses more than the bucket over the same 24-hour period, the difference is a leak, not the July heat. If they drop equally, you have normal summer evaporation and no structural problem to address. See our pool leak detection page for the complete bucket test procedure.

What a Summer Pool Leak Looks Like

Pool leaks that develop or worsen in summer are often thermal stress failures at the waterline tile. Placentia's summer pool water temperatures rise substantially in July, and the thermal differential between the warm pool water and the cooler air above the tile line creates expansion and contraction cycles in the plaster at the waterline. Plaster that has already been thinning through years of hard-water mineral exposure is more vulnerable to these thermal cycles. Small cracks at the tile line that were not leaking in winter may begin losing water as the seasonal temperature cycling stresses the already-weakened plaster.

Underground pool plumbing also behaves differently in summer: the soil around buried PVC pool plumbing expands slightly as it heats, and PVC fittings that held through a wet winter may develop small gaps at joints as the soil movement applies new stress to the fitting connections. Air bubbles returning through the jet inlets during pump operation are the diagnostic signal for a suction-side underground plumbing failure, and this signal is more commonly reported in summer than in winter for this reason. See our inground pool leak detection page for the underground plumbing pressure testing sequence.

For any Placentia pool that fails the bucket test at any time of year, call (714) 750-8637 for a complete shell and plumbing inspection. We cover all Placentia neighborhoods and adjacent North OC cities on the same dispatch line.