How to Find a Pool Leak (Step-by-Step)
Empire Pools uses a proven process to confirm whether water loss is evaporation or a true leak, then pinpoint the source before repairs. Use the steps below to diagnose safely and efficiently — and know when it’s time to bring in a pressure test or pro repair.
DIY Steps to Confirm & Locate a Pool Leak
- Step 1: 48-Hour Hold Test (System Off). Turn off pumps and auto-fill. Place tape on the skimmer faceplate to mark water level. After 48 hours, compare the drop to your mark. If it falls more than typical evaporation, proceed to the next steps. Tip: Cover the pool at night to reduce wind/evaporation variables.
- Step 2: Bucket Test (Evaporation Control). Fill a bucket, set it on the top step so water inside matches pool level, and weigh it down. Mark both levels. After 24–48 hours, compare drops. If the pool drops faster than the bucket, you likely have a leak.
- Step 3: Pad & Plumbing Inspection. Check the equipment pad and surrounding soil for dampness, white scale/salt trails, or air bubbles under the pump lid (suction-side leak indicator). Tighten unions and inspect valves.
- Step 4: Dye Test at Penetrations. With the system off and water still, release a small dye stream around returns, skimmer throat, main drain cover, lights/niches, steps, and seams. If dye pulls in, that point is suspect.
- Step 5: Isolate Lines. Plug all returns and run a single return at a time (or single skimmer) to see if loss accelerates when a specific circuit is active. Note changes.
- Step 6: Liner & Structure Check. For vinyl, inspect seams, corners, ladder/step gaskets, and around fittings for pinholes or separations. For gunite/fiberglass, look for cracks or loose light conduits.
- Step 7: Pressure Test (Pro Step). If the hold/bucket tests suggest a leak and you can’t locate it, schedule a line pressure test to confirm which run is compromised before digging or cutting.
- Step 8: Stabilize or Repair. Apply an underwater vinyl patch to small liner tears or a two-part epoxy putty for minor fitting cracks. For confirmed plumbing or structural issues, schedule professional repair.
- Step 9: Re-Verify. Repeat the 24–48-hour hold test after the fix to confirm water level stability.
What You’ll Need
- Masking tape & marker (for water-level marks)
- 5-gal bucket (weighted)
- Dye syringe or food coloring for leak checks
- Goggles/flashlight for close inspection
- Vinyl patch kit / two-part epoxy putty (minor repairs)
- Winter plugs / test plugs (for isolating lines)
- Optional: pressure gauge/rig (pro testing)