The most important thing needed for creating a waterfall or cascade is a change in level. This can be done by placing a water source above the pond, or by placing one pond higher than another.
If your garden doesn’t have a slope, raise the top pond by building up the soil or by making an above ground pond. Alternatively, you can excavate a hole for the lower pond.
Water will never flow uphill unless you force it to do so. If you want a continuous waterfall, you will have to install a pump. To operate the pump you will have to install electricity at the beginning of construction works.
The Water Outlet
When designing your waterfall, you will need to decide where to position the water outlet.
You can disguise the outlet by hiding it within the rocks on the high side of the top pond. This will create the illusion that the water is from a natural source.
Alternatively, you can make a bold feature of the water outlet by pumping the water into a fountain in the top pond. This approach will work well with formal ponds.
Because the water is flowing through a living system, you should always include a filter to remove unwanted particles from the water. This will prevent silting of the pump and keep the water clean for plant and animal life.
Formal waterfalls are usually symmetrical and may be complemented with formal plantings such as topiary. Concrete is a great material for formal waterfalls.
Vinyl liners are very flexible and offer great potential for creative landscaping. Naturalistic waterfalls should be positioned to use the existing slope of the site. If the water feature is sited at the lowest point in the garden, it will collect the natural water run off from your property and will sometimes flow without you having to turn on the pump!
In situations where there is only a slight slope on your property, it can be difficult to create a change in level that is large enough for a waterfall. This is ideal for a cascade – a series of ponds connected by small waterfalls.
Cascades look best when they are made using ponds of different sizes and with a range of level changes between the ponds.
Cascades can have a natural look that is particularly suited to informal gardens. You can achieve this look by including rocks and adding water-loving plants such as rushes and sedges alongside the stream.
If your garden is more formal in design, then the cascade should be made from geometric ponds that gradually increase in size as they go down the slope. The ponds could include statuary or other features to provide interest.
When building a cascade you need to ensure that there are no leaks in the system.
The vinyl liner must be cut so that the edges of the liner are above the water level. The liner needs to be carefully installed on a bed of thick sand and protected from possible damage by rocks, stones and sharp objects.
If the cascade is made from concrete ponds, the concrete must be made waterproof by adding a sealing compound to the concrete mix or coating the cured concrete with a sealant.
THINGS TO REMEMBER
Water prefers to go under rocks. Design your waterfall so that the water falls on top of the rocks.
Shade can make water depressing. Allow as much light on your waterfall or cascade as possible.
Shallow water gets hot and weeds can breed quickly.
Water should always look ‘full’ and go up to the edge of the pond
Where the top pond needs to be elevated, don’t place it above eye level.
Water features can be a beautiful addition to your garden, but make sure you prevent children from getting to deep water. If you have a deep water feature, fence it and make sure your gate is child proof. The gate should have a child proof latch and should close automatically.
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