Garden Watercourses and Cascades
Preformed units are available in a variety of materials: fiberglass, plastic, cement and reconstituted stone. Preformed units have many positives attached to their reputation; several designs and sizes are available, some contain preformed pockets for water plants, all are made to flow smoothly and pour water neatly from unit to unit. Preformed units can deal with a decent range of flow rates anywhere from fifteen to more than one hundred liters of water per minute.
The most popular preformed units are made of fiberglass because they are both lightweight and reasonably strong. This material can easily be designed to mimic natural rock and is frequently given a coat of grit or sand to further enhance its rustic appeal. Plastic units come in many sizes and shapes but require careful anchoring so they may not be dislodged by inclement weather. Plastic units are more inexpensive, but their uniform color makes camouflaging them difficult. Concrete and reconstituted stone are more expensive, but far more substantial and enduring. They also blend into the landscape far more effortlessly than other materials.
Liner constructed cascades and waterfalls are also available in many sizes and designs. If the landscape in question is large, than almost certainly a liner constructed watercourse should be considered. Preformed units become easily dwarfed by expansive surroundings. Liner constructed cascades can be adapted to both formal and informal gardens and they may be used to create nearly any desired size waterfalls. Liners are made of waterproof material that stretches along the course of the water.
Over the liner, materials such as pebbles or stone would be placed for rustic cascades. Formal cascades might employ mosaic designs, bricks or decorative tiles. It's best to purchase high quality butyl rubber liners as they are flexible, strong and will conform well to any course design. However, even more inexpensive liners may be sufficient when covered by pebbles or stone which will actually protect it from degradation by the sun.
When designing your course, you may employ a single cascade that flows into a pool or even a series of cascades and pools depending on how elaborate a landscape you desire. Liners are often used for streams, but they are seldom attractive when the water is turned off; consequently, most are purchased for cascade designs. Careful planning is required for both preformed units and liner constructed watercourses. If your landscape has an area that naturally slopes, this might be the ideal situation for either type.
Also, give careful consideration to the water pump which is, of course, the engine of your cascade or waterfalls. Output figures will indicate performance levels of any given pump. Pumps that employ high maximum heads are ideal for tall waterfalls as they are suited to high pressure flows. You'll also have to decide between submersible and externally mounted pumps. Submersible are the most popular choice, but external pumps are used because there is no pump or cable to be seen in the water and they can easily be hidden out of sight. There are many different types of pumps available so be sure to take care to choose a model that is in keeping with your cascade's specific needs.
For many water gardeners, the fun begins once the watercourse or cascade has been installed. Be sure to give it a test run before you anchor it firmly into place. Once installation is complete, the landscaping can be attempted. Keep in mind that many water plants or marginals can be very aggressive. Whenever possible, contain these varieties nearby. Many water gardeners take care to landscape with plants that will blend in with the rest of the landscape and help make the watercourse appear more natural. In any case, your watercourse or cascade is bound to become the focal point of your landscape.