Installing EPDM Pond Liner

Step 1: Decide on the position and size of your pond
Consider the siting of your new pond carefully - once a pond is installed it is not an easy thing to move! Also consider the available roll width sizes, before beginning your excavation. (See Step 6.)

Sunlight: Is important for all pond life. Water lilies particularly need plenty of sun to flower at their best.

The more sun your pond receives the bigger the filter you require. If your pond receives full sun, you will need to allow for a filter that can cater for 50% more water than your pond holds.

Beware of Trees: A pond too close to trees and bushes will soon have many leaves in the bottom.

These decay in the pond and become dangerous when ice forms and stops the poisonous gas escaping from the water, killing your fish. Tanin from gum leaves stains water a tea-colour.

Contamination: If you site your pond at the lowest part of the garden, remember that when it rains water from the lawn could run into the pond.

If you have applied fertilizer, weedkiller or insecticide and it is washed into the pond it will probably kill the fish and may harm the aquatic plants.

Site the pond at a higher point, or arrange the run-off so that it cannot cause contamination. If you build a rockery or waterfall by the pond, be sure to arrange the rocks and planting pockets so that the soil will not wash into the pond and make the water dirty.

Depth: You should try to have one area at least 600mm deep to provide a cool refuge for fish in the summer.

Local Council authorities may require a pond deeper than 300mm to be fenced.

Using a rope or your garden hose to indicate the outline of your proposed pond.

Step 2: Begin digging your hole
Using a spade, carefully cut within your rope or host marker and remove one spade width of turf or topsoil around the outline of the pond.

This gives you a good impression of the final appearance of the pond, and it is easy to make adjustments.

Step 3: Prepare the edge of the pond

 

It is important to make sure the edge of the pond is all one level.   Build up soil at low points if necessary, and cut down high points with your spade.  

Use a board and a spirit level, or a clear hose filled with water to make sure this is correct.   You will be laying the 300mm overhang over this prepared edge, and then landscaping over the top of the liner upon completion.  

Bushrocks and/or river pebbles are usually used to achieve this.

Step 4: Completing the excavation

This is where the hard work starts!   Carefully excavate your hole.   If you want to reuse your turf elsewhere, make sure you remove it with at least 25mm of soil.  

Good topsoil should be kept for use in the garden you will later build around your pond.   Subsoil and rock is used to build up your waterfall if necessary, or will need to be disposed of.  

Mark out where plant shelves are to be left in your pond and cut with the spade to this level.   Aim to keep the sides of your pond at as gentle a slope as you can to prevent too many wrinkles in the EPDM Rubber.  

Plant shelves enable you to have steeper sides because plants growing on the shelves hide wrinkles in the liner behind them.

Remove any sharp stones as you go.

Step 5: Protecting the liner from punctures

You should always line your hole with a layer of sand to protect the liner against punctures.   Whilst no guarantee can be provided against puncturing, sand acts as a protective cushion.  

You can also use old carpet.

 

Step 6: Work out the size of EPDM Rubber Liner you require  

Rolls are 15.2m or 30.4m long, and we cut to the length you require.  

EPDM Liner is available in the following different widths:  

2.44m, 3.05m, 4.57m, 4.88m, 6.10m, 7.62m, 9.15m, 12.20m,15.25m 

Measure your pond after you have excavated the hole using a length of string.   Run the string through the pond, following the profile you dug, along the two longest dimensions.   Ensure you allow for a 300mm overhand on each side for edging.

Step 7: Lay the liner in the hole

Lay the liner in the hole, roughly in position, weighing the sides down with a few bricks to keep it in place

 

Step 8: Fill the pond

Fill the pond with the garden hose.   As the pond fills, walk around in the pond levelling out the wrinkles, and adjusting the liner to suit.

Step 10: Set up waterfalls, pumps and filtration

Waterfalls, pumps and filtration requirements vary with every pond.    It is a good idea to circulate the water in your pond at least once per hour in Australian conditions.

To calculate the rough volume of a pond constructed in this manner, use the following formula:

Length x Width x Depth ¸ 2 (because your pond slopes in this approximation is close enough) 

When trying to work out how much water flow you require over a waterfall, you will find you will need approximately 225L/hr for every 2.5cm of waterfall lip width.   This means if you have a 30cm wide waterfall, you will need a pump that delivers 2700L/hr at the waterfall height.   You will find full details on all pumps we sell and recommend, including Hozelock Cyprio, Resun, and Zenit at our online store: http://www.rockaroundtheblock.com.au

If you have any further questions, give one of our friendly staff a call on 1300 733 113.