Why does my Pond or Waterfall leak?

You have enjoyed your Pond or Pondless waterfall for sometime now without issues, then out of the blue you spring a leak. Leaks typically don’t happen all of a sudden. Usually the problem happens slowly until one day it becomes very noticeable.

What causes leaks in a Pond or Pondless waterfall? Before we answer, it has to be said, that the majority of leaks are located in the waterfall / stream and not the pond.

Michele and Ethan preparing a liner on a Pondless Waterfall

Michele and Ethan preparing a liner on a Pondless Waterfall

How to do a leak test to find out if your leak is in the pond or waterfall. Turn pump off, wait 1/2 hr and note the level of the pond. Check level 24hrs later and if the water level has not gone down most likely the leak is in the stream or waterfall.

Causes – Ponds and Waterfalls with a liner membrane

Low Edge –

Our ponds and streams are constructed with an EPDM rubber liner that keeps the water within the system. When an ‘edge’ drops water can trickle over the edge into the landscape and after a short period of time the water loss is noticeable. This type of leak is usually easy to find and fix. To fix you simply pull liner up and backfill with soil to hold liner up.

What causes a low liner edge?  There are a few  causes to a low liner edge including settling of the backfill material, plants in the planting bed next to the liner sending roots over for water and gophers / moles burrowing under rocks and in the planting bed. Add a little rain or an aggressive watering system and the soil will settle or get washed away, thus causing the liner to settle with the soil.

Other causes of leaks we have encountered include that may be harder to find, but occur less often. These situations are all fixable.

  1. Irrigation stakes placed inside and through the pond or stream liner by a home owner or gardener.

    Mature planting around this Pondless™ Waterfall

    Mature planting around this Pondless™ Waterfall

  2. Lighting stakes and other garden art placed inside and through the pond or stream  liner by a homeowner or gardener.
  3. Critters including moles and voles chewing through liner. (in the waterfall not pond)
  4. Tree roots (Fig tree) Once. (Stream)
  5. Plants in the stream growing and left unchecked for too long causing the water to rise in the stream bed and go over an edge.
  6. Plants located in a Biofall filter left unchecked for too long, causing a leak at the biofall.
  7. Bolts at the skimmer faceplate may become corroded and the seal between the liner and skimmer can be compromised.
  8. Bolts at the Biofall filter may become corroded and the seal between the liner and Biofall can be compromised.
  9. Kids building a Dam with rocks causing the water to go over an edge.
  10. Plumbing connection from pond to waterfall.

One caution, an autofill device can mask a leak for some time. It is a good idea to turn the water supply off to the autofill device every now and then to see how the system is holding water.

The good news is that pond or stream constructed with EPDM liner means all of these situations are fixable. EPDM liner is flexible and will flex with the ground, concrete will not flex and will crack. With concrete the term fixable is usually not a choice or even discussed.

Do you have a pond or waterfall with a leak? Lets us know here.

Proper construction techniques mean this pond will not leak.

Relax and enjoy a leak free pond and waterfall