How much water a pool loses to evaporation
In July and August the sun and the wind take 5–8 mm off the surface every day. That adds up to 3.5–5.6 cm a week, so on a hot, windy week evaporation alone comes close to the 5 cm mark. In spring and autumn it is lower. The table shows what the drops mean for an 8×4 m pool, which has 32 m² of water surface.
5 mm a day (3.5 cm a week)
Water lost from an 8×4 m pool: About 1.1 m³ a week
What it usually means: Normal evaporation in summer
8 mm a day (5.6 cm a week)
Water lost from an 8×4 m pool: About 1.8 m³ a week
What it usually means: The top of the evaporation range: hot, windy weeks
1 cm a day (7 cm a week)
Water lost from an 8×4 m pool: About 2.2 m³ a week
What it usually means: More than evaporation explains. Do the bucket test
2–3 cm a day
Water lost from an 8×4 m pool: About 4.5–6.7 m³ a week
What it usually means: Far past the 5 cm mark. Ask for a leak check
| Level drop | Water lost from an 8×4 m pool | What it usually means |
|---|---|---|
| 5 mm a day (3.5 cm a week) | About 1.1 m³ a week | Normal evaporation in summer |
| 8 mm a day (5.6 cm a week) | About 1.8 m³ a week | The top of the evaporation range: hot, windy weeks |
| 1 cm a day (7 cm a week) | About 2.2 m³ a week | More than evaporation explains. Do the bucket test |
| 2–3 cm a day | About 4.5–6.7 m³ a week | Far past the 5 cm mark. Ask for a leak check |
The bucket test, step by step
It is the oldest pool trick there is, and it works because the bucket and the pool lose water to the same sun and wind. Pick a day without rain.
- Top the pool up to its normal level and turn off any automatic filler.
- Fill a bucket with pool water and stand it on the first or second step, so it sits in the pool. Put a brick in it if it floats.
- Mark the water level inside the bucket. Mark the pool level on the outside of the bucket, or with a strip of tape on the skimmer opening.
- Leave it 24 hours with the pump running on its normal timer. Nobody swims and nobody tops up.
- Compare the two marks. If the pool dropped more than the bucket, the difference is a leak.
- Repeat with the pump off for 24 hours. If the result changes a lot between the two days, the leak is likely in the pipes or the equipment, which tells the company where to start.
One more thing to watch: a leaking pool left with the pump off often stops dropping at the height of the leak, for example just under the skimmer mouth or at the light. Note where it stops, but don't let the level fall below the skimmer while the pump is on, or the pump runs dry.
Where pools leak
- The skimmer, where the box meets the pool wall.
- The return fittings, the jets in the wall that push the water back in.
- The pipes under the deck. Look for a wet patch in the garden or around the plant room, or air in the pump basket.
- The light niche and the conduit that carries the cable.
- Cracks in a concrete shell, often near tiles that sound hollow or have come off.
- The liner: a tear, a seam, or simply age. The July sun on the island wears liners faster, and they last 10–15 years.
A drip at the pump or the filter in the plant room counts too. It is the easiest one to see, so look there before anything else.
What pool leak detection and repairs cost
One Paphos pool company's April 2026 price list puts leak detection at €250–400. That pays for finding the leak. The repair is a separate price and depends on what they find: a skimmer seal or a fitting is a small job that the company prices after the visit, while the same list gives €3,000 and up for a new liner and €5,000 and up for structural work on the shell.
- Pump repair
- €100–300
- New pump, fitted
- €300–800
- Leak detection
- €250–400
- Salt cell replacement
- €400–600, every 3–5 years
- New liner
- from €3,000
- Structural repair of the shell
- from €5,000
What pool companies on the island charge, from their own price lists, property guides and listings (October 2026); VAT is not always included. The company that takes your request names the exact price once it has seen the pool.
Why a leak costs more now
2025 was the driest year in Cyprus since 1901, as Cyprus Mail reported in December. Water is short, and a leak that keeps the hose running all summer shows up on the bill.
In Limassol the water board (EOA Lemesos) bills per four-month period: €0.90 a cubic metre for the first 40 m³, €1.43 for 41–80, €2.45 for 81–120 and €5.00 above 120, plus €22 fixed. Take an 8×4 m pool in Ypsonas losing 1 cm a day more than evaporation would explain. That is 0.32 m³ a day, about 38 m³ in one four-month bill. If the house is already above 120 m³ for that period, the leak alone costs about €190 at the top rate.