During the blistering summer months in the Inland Empire, backyard swimming pools in North Rialto and El Rancho Verde face intense sun and dry winds. Homeowners frequently notice their pool water level dropping by 1/4 inch or more per day, prompting the urgent question: Is my swimming pool just evaporating in the Rialto heat, or do I have a hidden underground plumbing leak?
Evaporation vs. Structural/Plumbing Leaks
Normal summer evaporation in San Bernardino County accounts for approximately 1/4 inch (and occasionally up to 1/2 inch on hot, windy days) of water loss daily. However, if your pool is losing 1 inch, 2 inches, or more every 24 hours, thousands of gallons of water are escaping into the surrounding subsoil, threatening pool foundation stability, eroding equipment pads, and inflating your Rialto Water Services bill.
The 5-Step DIY 24-Hour Bucket Test
Before scheduling a professional diagnostic, perform this simple scientific test to determine whether your water loss is normal evaporation or an active leak:
- Bring Pool to Normal Operating Level: Fill the pool to the middle of the skimmer opening as usual. Turn off the automatic water auto-fill float valve during the test.
- Fill a 5-Gallon Plastic Bucket: Place a clean 5-gallon bucket on the first or second step of the pool so it is partially submerged in pool water (this ensures bucket water and pool water stay at the exact same temperature). Fill the bucket with pool water until the water level inside the bucket is within 2 inches of the top rim.
- Mark Both Water Levels: Using waterproof tape or a grease pencil, mark the water level ON THE INSIDE of the bucket. Then mark the pool water level ON THE OUTSIDE of the bucket.
- Wait Exactly 24 Hours: Run your pool pump on its normal timer schedule. Ensure no rain occurs and keep swimmers and pets out of the pool during the 24-hour test period.
- Compare the Measurements: After 24 hours, measure the drop in the bucket vs. the drop in the pool:
- If both levels dropped by the exact same distance: Your water loss is 100% due to environmental evaporation!
- If the pool level dropped significantly more than the bucket level: You have an active plumbing or structural shell leak!
Where Do Pool Leaks Typically Occur?
If the bucket test confirms a leak, our certified technicians use hydrostatic pressure testing to isolate suction lines, main drains, return lines, and skimmer throats, along with syringe dye testing along light niches and tile grout seams. Explore our complete pool and spa leak detection services to stop water loss fast.