If you own a pool in Las Vegas, you already know that keeping water in it can feel like a full-time job during the hottest months of the year. Between triple-digit temperatures, intense sunlight, low humidity, wind, splashing, and normal evaporation, your pool can lose a noticeable amount of water without anything actually being wrong.

But there comes a point when normal water loss starts looking a little too normal.

Maybe you’re filling the pool more frequently than you remember. Maybe your autofill seems to run constantly. Or maybe you’ve noticed the water level dropping every time you shut the autofill off.

Before assuming you’ve got a leak, there’s a simple test you can perform at home. It’s called the bucket test, and it’s one of the easiest ways to compare your pool’s water loss against natural evaporation.

What Is the Pool Bucket Test?

The idea behind the bucket test is pretty simple.

Water inside your swimming pool is exposed to the same weather as water sitting in a bucket next to it. Both are dealing with the same Las Vegas heat, sunlight, wind, humidity, and overnight temperatures.

By placing a bucket partially submerged in the pool and comparing the water loss inside the bucket with the water loss in the pool, you can get a much better idea of whether evaporation is responsible for your disappearing water.

If they lose roughly the same amount, evaporation is probably playing a major role.

If the pool loses noticeably more water than the bucket, there’s a good chance something else is going on.

How to Perform a Bucket Test

You don’t need any special pool equipment for this. Grab a clean five-gallon bucket, a marker or some tape, and give yourself about 24 hours.

1. Turn off the autofill. This is important. If the autofill continues replacing water during the test, you won’t get an accurate measurement.
2. Fill the pool to its normal operating level. Don’t intentionally overfill it. You want to test the pool under normal conditions.
3. Place the bucket on a pool step. Add pool water to the bucket until the water inside the bucket is approximately level with the pool water outside of it. The bucket should be stable and partially submerged, but don’t allow pool water to wash over the rim.
4. Mark both water levels. Mark the water level inside the bucket and the pool water level on the outside of the bucket. Tape works well if you don’t want to mark the bucket permanently.
5. Leave everything alone for approximately 24 hours. Avoid swimming, adding water, backwashing the filter, or doing anything else that could substantially change the pool level.
6. Compare the results. Measure how far the water dropped inside the bucket and compare it with how far the pool water dropped outside the bucket.

The difference between those two measurements is what you’re interested in.

How to Read Your Bucket Test Results

If the water inside the bucket and the water in the pool dropped by approximately the same amount, the water loss you’re seeing may simply be evaporation.

That’s particularly important here in Las Vegas.

Our climate can produce substantial evaporation, especially during periods of extreme heat, low humidity, wind, and prolonged direct sunlight. A pool with a large surface area may naturally lose more water than a homeowner expects.

However, if the pool water drops noticeably more than the water inside the bucket, that additional loss may indicate a leak.

For example, suppose the water inside your bucket drops 1/4 inch over 24 hours while the swimming pool drops 3/4 inch. The weather affected both bodies of water, but the pool lost an additional 1/2 inch.

That’s something worth investigating.

And half an inch may not sound like much until you consider the size of a swimming pool.

A 15-by-30-foot pool contains approximately 280 gallons of water for every inch of depth. An unexplained half-inch of water loss could therefore represent roughly 140 gallons in a single day.

Over a month, that’s thousands of gallons of water going somewhere it shouldn’t.

Try the Test With the Pump On and Off

If your initial bucket test suggests a leak, you can gather another useful clue by repeating the test under different operating conditions.

Run one test while the circulation system operates normally. Then perform another with the pump off.

If the pool loses substantially more water while the pump is running, the problem may be associated with the circulation system or pressure-side plumbing.

If the pool continues losing water at a similar rate with the equipment off, the leak could be somewhere in the pool structure, skimmer, light niche, fittings, suction plumbing or another location.

This isn’t enough information to definitively locate a leak, but it can help narrow down what’s happening.

What If the Water Keeps Dropping and Then Stops?

This is another clue we pay attention to.

If a pool repeatedly loses water until it reaches approximately the same elevation and then stops, look at what’s located around that waterline.

Is it near the bottom of the skimmer opening? A return fitting? A pool light? A crack? A penetration through the pool shell?

Sometimes the level where the water stops can provide an important clue about where water is escaping.

That doesn’t mean you should intentionally allow a pool to drain several feet trying to find the leak. Running equipment with an inadequate water level can create an entirely different set of problems.

Don’t Forget About the Autofill

Autofills are convenient, but they can make pool leaks surprisingly difficult to notice.

A pool can lose water every day while the autofill quietly replaces it. From the homeowner’s perspective, the water level looks perfect.

The first sign of trouble may instead be a higher water bill.

If you’re suspicious about your pool’s water usage, shut the autofill off before performing the bucket test. Otherwise, you’re essentially trying to measure a leak while another device is continuously replacing the missing water.

The Bucket Test Tells You If You May Have a Leak — Not Where It Is

This is the most important thing to understand about the bucket test.

It’s a diagnostic starting point.

It doesn’t tell you whether water is escaping through a skimmer, plumbing line, fitting, light niche, crack, equipment connection or another part of the pool.

That’s where professional pool leak detection comes in.

Depending on the symptoms and pool, locating a leak can involve inspecting the pool and equipment, isolating plumbing, pressure testing lines, testing suspected areas with dye, checking fittings and penetrations, and working systematically through potential leak locations.

The goal isn’t to start tearing things apart looking for water. It’s to identify and isolate the source of the loss before deciding what needs to be repaired.

Think Your Las Vegas Pool Is Leaking? Let’s Find Out.

If your bucket test shows the pool losing more water than evaporation can account for, don’t keep feeding it water and hoping the problem goes away. A small leak can waste a surprising amount of water over time, and the source isn’t always obvious from the surface.

Las Vegas Pool Bros offers professional pool leak detection throughout the Las Vegas area to help determine where your water is going and what needs to happen next.

Run the bucket test first. If the numbers don’t add up, schedule a leak detection service with Las Vegas Pool Bros and let us track down the source.