FLEXIBLE POND LINERS


Before installing your pond, you must decide on how you will configure your pond.  How will you create the pond's edging?  Do you need a site plan before you begin?  You can't simply dig a hole in the ground and expect it to hold water.  You will first need to provide a foundation that is water tight.  Since most of today's ponds are built with either a preformed shell or a flexible liner, you can create a formal or informal pond of your choice.  You will also need to provide an edging to mask the rim of the liner.  The edging can be an important asset as it helps an informal pond blend into the landscape.  The pond shown left, below is an example.  Notice how they blended the pond into the surrounding landscape.

Although they are called flexible because of their pliability, the biggest selling point for a flexible liner is their design options.  They are very popular with Koi pond fish hobbyists because you can make a flexible liner adapt to your design.  You can build a winding stream or a waterfall.  Flexible liners are also relatively inexpensive and easy for do-it-yourselfers to install.  You lay the liner in the hole, fill the pond with water, trim the liner and then install the edging.   Drs. Foster and Smith.com carry a complete pond kit if you are just getting started,  as shown top left.  This kit has everything you need to get started with your koi fish pond, a liner, filter, tubing, pump and is very reasonably priced compared to buying each piece individually.                                               

Liners made especially for ponds are either PVC or synthetic rubber.  Naturally the best liners cost more.  Thicker liners usually last longer.  Liners are available in thickness from 20 to icon32 millimeters and will typically last from 5 to 15 years depending on the quality.  Naturally a 32 mill liner will last longer than a liner of only 20 mills.  They come in various sizes ranging from about 5 x 5 feet to 30 x 50 feet.  Some manufacturers even offer custom sizes priced by the square foot.  By using a seam sealer, you can literally create any size or shape koi pond, just by cutting and seaming the pieces of your liner together to conform to your desired shape.

Because flexible liners are susceptible to punctures from rocks, gravel, broken tree roots, or other sharp objects, you should use some type of underlayment to cushion the liner.  A carpet pad is one possible choice.   Most water-garden suppliers offer a tough, flexible underlayment material specifically designed for use with pond liners.

If you have especially rocky soil, or if it is full of roots or even subject to excessive shifting during the winter months, then you should install both a layer of sand and underlayment fabric.   The underlayment fabric above right is perfect for your pond as it will protect not only against punctures and tears, but it is also a durable safe and clean material to install under your pond liner.  The underlayment will help to extend the life of your pond.

If,
however, the soil is rock free, and stable you can skip the underlayment as it really isn't needed.  Sand will work just as well, as it did in my own koi pond.  If you are working on a tight budget, this is one place you can save money and still  create a fabulous looking pond!