A rock cascade adds value to your pool surround by giving it visual animation and the sound of cascading water
One of the simplest ways of adding interest to your garden is by constructing a rock cascade as part of your pool. Most DIY enthusiasts will manage this project fairly easily because you will be using an existing water source when building the focal feature.
Getting the basics right
Rock cascades are typically built on the walkway around your pool and brickwork, or a mound of sand, can be used to create the elevation needed for the cascade. If you’re using brickwork then the stones should be fixed into place with building mix. A cement additive, like bonding liquid, should be used in the building mix to decrease the permeability of the cement. Make sure that the stones you use are resistant to pool chemicals. If you are using a mound of sand for the embankment, a base layer of waterproofing material or concrete should be used to cover the sand and the stones are then fixed into place with cement.
- PVC or polyethylene (irrigation) piping to run water from the pump to the feature
- T piece and 2 valves
- Electric cord
- Waterproof liner
- Rocks that have been thoroughly cleaned
Where to start
- First decide where you want the cascade, keeping the power and water piping layout in mind.
- Dig a trench for the water pipe from the pump to the cascade. Insert the T piece in the pressure pipe where it exits the filter and connect the pipe from the cascade to the T piece. Install the valves. You can also use a separate pump to power the water, but this will require a dedicated suction point in the pool in the form of a new weir – this isn’t advisable as it can cause a lot of damage to an existing pool.
- Use the displaced soil from your excavations for the electric or water tubing to build an elevated area for your cascade. Lay the waterproof liner along the path of the water cascade, pinning it down with stones. Two layers of liner are recommended for the cascade as waterproofing – one for the splash and one for the actual path of the water. Note: make sure the liner drapes underneath the waterfall spillway stones otherwise you will experience water loss when the waterfall is in operation. Also, the liners must be placed so that no soil will be washed into the pool during a storm.
- Route the pipe for your cascade to the stones. Take care when hiding piping and liner – do not pinch or kink either, as this may reduce the water flow over time.
- Once the spillway liner and piping are in place, pump some water and watch it flow down the liner. Carefully select stones and position them – while the water is flowing. With the water flowing over the rocks, you can replace, shift and add stones so that you achieve the desired water spills you want.
Brick and stone cascade
- The steps to create a brick and stone cascade are similar to the above except that concrete and bricks are used to create the height for the cascade and each level within the feature.
- Some waterproof rock-lights work best for a cascade and draw minimal voltage. During the installation ensure that the electric cable is run in a suitable underground waterproof conduit like PVC or polyethylene piping and install a circuit breaker for safety. Remember that all lights in and around water must be 12 volt.
- The easiest way to install lighting is to use products specifically made for water features, like the Lirio Lights range by Waterfall Pumps. These submersible kits can be used in the garden, in all weather, or under water and come with four coloured lenses to change the effect. They have a base that can be weighed down with stones or sealed so that it can float on water, or they have a stake attachment that can be used to position them in the garden or in a tree. These lights simply plug in and can be moved at any time. Lights embedded into faux rock are also available.
- Moss and small plants can be placed between the stones around the waterfall to give it a softer, more natural look. However, this does create the problem of plant matter and soil being washed into the pool during a storm. To overcome this problem it is advisable to first plant the plants in containers or bidum pockets before placing them.
Article Source: http://www.thegardener.co.za/kb/article.php?id=266