Pool Losing Water? Water Loss, Evaporation, or Leak?

Is your pool’s water level always dropping, leaving you frustrated and wondering what’s going on? If your swimming pool is losing water every day or you wake up to see the water level lower each morning, you’re not alone. Many San Antonio area pool owners face water loss–whether it’s due to natural evaporation or a hidden pool leak. Understanding the causes of pool water loss is essential to keep your backyard pool safe, efficient, and enjoyable. At South Texas Pool Leak Detection, we use industry-leading LeakTronics equipment to pinpoint the exact location of leaks and help you fix pool leaks before they become bigger problems. This article will make sense of why your pool loses water and share practical pool care tips for San Antonio homeowners.

Why Does My Pool Lose Water Overnight?

Pools lose water overnight for a few main reasons: evaporation, leaks, or a combination of both. On a hot, windy night, water and heat work together to cause water to evaporate from your swimming pool. However, if your pool water loss is significant or you notice soggy spots around the pool, you may have a leak in your pool. Pay attention to how much water your pool is losing water overnight—if it’s more than 1/4 inch, that’s often a sign of a leak, not just evaporation.

Pool Water Loss: How Much Is Normal?

A pool’s water level will naturally drop a little each day due to evaporation—usually about 1/4 inch of water per day, depending on San Antonio’s temperature, wind, and humidity. Factors like pool features (waterfalls, fountains), lack of a pool cover, or uncovered water overnight can increase evaporation. If your pool loses water beyond this amount, there’s likely an underlying issue that needs attention.

Evaporation or a Leak: How Can I Tell The Difference?

To find out if your pool is losing water due to evaporation or a leak, try the “bucket with water” test.

Fill a bucket with water and place it on a step in your pool so the water level in the bucket matches the pool’s water level.
Mark the water level on both the bucket and the pool.
After 24 hours, compare the water loss. If both levels drop the same, your pool is losing water due to evaporation. If the pool water level has dropped more than the bucket, you may have a leak in your pool.

If the difference is more than about a quarter-inch a day, you may have a leak instead of just evaporation.

Common Signs of a Pool Leak

If your swimming pool is losing water overnight, look for these signs that indicate a leak:

Water loss is greater than normal even in mild weather
Wet spots or soggy ground around the pool
Cracks in the pool structure or on the side of the pool
Bubbling in the pool pump system, which can mean air is getting drawn into the lines
The pool loses water even when the pump is off

Why Does My Pool Lose So Much Water Every Day?

Things that cause water loss in a pool faster than evaporation include:

Pool leaks (often in plumbing, fittings, skimmer, or pool structure)
Faulty pool pump or leaky valves
Cracked pool surfaces or damaged liners
A leak in the skimmer or bottom of the pool

Addressing these issues fast is crucial to keep water in your pool and avoid high water bills in San Antonio.

Pool Leak Detection: How Do The Pros Find Out If Your Pool Is Leaking?

At South Texas Pool Leak Detection, we use LeakTronics’ professional-grade leak detection equipment. Our leak detectors listen for the exact sound of water escaping from pool pipes or pool structures. We may use dye tests or pressure testing to find even the most hidden pool leaks. This non-invasive technology helps us find out the exact location of the leak so we can fix pool leaks quickly and efficiently.

What Should I Do If My Pool Is Losing Water Overnight?

First, check the water level in your pool every day for a week to see how much water is being lost. Perform the “bucket with water” test to see if the water loss is due to evaporation or a leak. If it’s greater than 1/4 inch per day, or you see soggy areas or cracks, it’s time to call for professional pool leak detection. Delaying pool repairs could lead to pool pump leaks, structural problems, or damage around the pool.

Pool Maintenance Tips to Prevent Water Loss

Regular pool maintenance can help prevent excessive water loss in a pool and may keep your pool’s water level stable:

Check the water for clarity, chemical balance, and debris daily
Use a pool cover at night and when not using the pool to reduce evaporation
Schedule regular pool service, especially before San Antonio’s peak swimming season
Inspect the pool structure for cracks and repair small damages before they become bigger leaks
Watch for signs the pool water level has dropped suddenly

What If My Pool Is Losing Water When the Pump Is On or Off?

If the pool loses water only when the pump is running, the problem could be on the pressure side of the pool pump system (like filter or return lines). If the pool is losing water when the pump is off, the issue may be on the suction side or within the pool itself (floor, steps, lights, or skimmers). Either situation calls for professional leak detection, since serious pool water loss can harm your pool equipment and cause costly repairs.

How South Texas Pool Leak Detection Can Help

If your swimming pool is losing water, don’t let the leak cost you time, money, and stress. At South Texas Pool Leak Detection, we offer comprehensive pool leak detection and repair for homeowners in San Antonio. We use LeakTronics’ innovative technology to provide accurate, fast service. Our local team knows the unique challenges of San Antonio pools—whether you’re dealing with evaporation or a leak, we’ll get to the bottom of your pool water loss.

Protect your pool investment. Our LeakTronics technology means we find pool leaks faster with less guesswork and disruption.

Key Things to Remember

A pool loses water naturally from evaporation—usually about 1/4 inch per day.
More significant water loss (especially water overnight) often signals a leak in your pool.
Use the bucket with water test to see if your swimming pool is losing water due to evaporation or a leak.
Common leak sources include poor pool structure, pool pump system leaks, and skimmer breaks.
Professional leak detection using LeakTronics equipment gets you reliable results for finding and fixing leaks.
Regular pool maintenance and inspections in San Antonio can prevent significant water loss and damage.
If you suspect a leak, don’t wait—call South Texas Pool Leak Detection for accurate, stress-free repairs and to keep your pool’s water level just right