How to Detect Pool Leaks & Budget Repairs

Is your pool losing water? In hot summer months, pools naturally lose **1/4 inch of water daily** due to evaporation. However, if you are losing more than that, you likely have a leak. Here is how to diagnose it and budget for repairs.

1. The Bucket Test Diagnostic

This simple, zero-cost test helps determine if water loss is due to evaporation or a physical leak:
1. Fill a standard 5-gallon plastic bucket with pool water to about 5 inches from the top.
2. Place the bucket on the first or second step of the pool (so it is partially submerged to maintain matching water temperatures).
3. Use tape to mark the water level inside the bucket. Also, mark the pool's water level on the outside of the bucket.
4. Wait 24 to 48 hours. Compare the levels.
- **Result:** If the pool water level (outside mark) has dropped more than the bucket water level (inside mark), you have a physical leak.

2. Identifying the Leak Source

- **Plumbing Lines:** Turn the pump on. If the water level drops faster when the pump is running, the leak is likely in the pressurized return piping.
- **Pool Shell:** If the water stops dropping at a specific level (e.g. exactly at the bottom of the skimmer throat or a light fixture), the leak is at that height.
- **Hydrostatic Valve:** A failing valve at the bottom of the deep end can allow water to drain into the ground below.

3. Repair Budgets

Leak repair costs vary widely based on location:
- **Professional Leak Detection Service:** Pressure testing lines and using underwater microphones costs **$350 to $650**.
- **Skimmer / Light Conduit Patching:** Simple epoxy or grout work costs **$400 to $800**.
- **Under-Deck Underground Pipe Repair:** Requires cutting concrete decking, excavating, and replacing piping. Costs range from **$1,500 to $3,500**.

Promptly repairing pool leaks prevents water from eroding the soil beneath your pool deck, which can cause concrete slabs to crack or sink.