Water Loss – Where does it go?

All pond owners deal with loss of water that seem in explicable. Once we rule out gaping holes in our liner we begin to wonder just where all that water can go. So here are some issues you may or may not be aware of.

Evaporation – In an open sunlight system with a black pond liner one can expect to loose about 1 inch per week due to evaporation. High temperatures and wind conditions may even raise it more.
Plant transpiration – IF you have a veggie filter or floating pond plants like hyacinth you could be losing up to 3 more inches per week due to the effect of water use by plants. Floating plants generally have large leaves which allow the water to transpire into the air as part of the natural photosynthesis process. Here is an interesting study done on the affects of hyacinth transpiration in a controlled system. It found that tanks with hyacinth lost 3-4 times the water than just a tank with no plants.
Siphon Action – The folds in your liner can act as a siphon. The folds form tubes for water to traverse either under pressure or because of overflow and waters innate stickiness which keeps it going. You can stop the siphon by folding liner back over itself or by placing a rock in the fold below the overflow point to widen the fold so the siphon is lost. You can also encounter a siphon by leaving a drainage tube in a pond after doing water changes and refilling. The static water pressure and air pressure changes may start the siphon process without your knowledge.
Ground Water – The accumulation of water beneath your liner after a heavy rain can sometimes creates a water bubble under your liner. Once the ground water is reabsorbed the liner flattens again and your water level in the pond drops.
Animals – If a herd of deer, racoons, and other critters visits your pond nightly they can drink a good bit of water in a week. Animals may also divert water in your streams such that the water does not return to the pond.

IF you have any other reasons for unexplained water loss feel free to share them in the comments section below.

UPDATE: An unusual solution that I found by accident … read more