Different Types of Pond Underlayment Material
Pond underlayment should be installed before the pond liner in water gardens and koi ponds to prevent punctures that could happen from rough and rocky ground. It also helps release gases from the earth. If you did not allow for this the pond liner could develop bubbles and rise into the pond.
The ideal material is going to be cost effective, lightweight, and will not biodegrade. In the past pond owners have tried all kinds of material before settling on non-woven geotextile pond underlayment. Here are some materials I have seen used:
- Sand - While sand is good for protecting horizontal surfaces and we do reccomend adding some sand even if using non woven geo fabric.. it has no way to protect the vertical surfaces. Rocks and roots will be able to push through these surfaces into the liner, or trap gases.
- Newspaper - Some downfalls of newspaper.. hard to collect enough of it, hard to apply in windy conditions, and also time consuming and biodegrades quickly.
- Old Carpet - Hard to find, diffcult to get to fit the shape of the pond, weight makes it labor intensive.
- Non-Woven Geotextile Pond Underlayment - Geotextile has become the most popular because it is cost effective, easy to install, and black in color for easy hiding. You can also use geo textile for drainage and erosion projects.
The other factor you should keep in mind if you are going to try and use something other than geo fabric is your time. The effort and cost of your time could be used other ways than collecting newspapers around your town, and you get the added bonus of enjoying your water feature faster.
Pond underlayment is often not given enough thought. But, when you think about the headaches from leaks, etc if not properly done it is well worth investing in good material.
This will give you peace of mind for years to come.