All about design of water feature fountains
When tackling the design of an architectural fountain, it is important to consider the various components. This is exactly what we intend to do in this, and future installments of this Blog.
Water feature fountains generally need to have a water tank, a pumping system and a series of technological and construction items that enable the water to remain in continuous motion.
1.- Water Tank.
Generally, a water storage tank should be fitted to allow for the architectural fountain to work continuously and for the water to be re-circulated, while ensuring that the minimum depth required for the pumps to work properly is maintained. Tanks can be either visible or concealed from public view. Visible water tanks are known as ponds and form part of the artistic design of the project. In such cases, their base shape and height above ground level may vary greatly. It is recommended that ponds whose only purpose is to form part of a water feature should be designed as shallow as possible to save water and to prevent accidents involving children.
When architectural fountains are operating, a certain volume of water runs through the piping, open ducts, jets and sprays. This volume of water is temporarily 'removed' from the water tank, so that a suitable depth of water – in the ‘basin’ - has to be left in the pond to ensure the pumps and the submerged nozzles, etc. work properly. The size of the water tank can be a 'critical' factor in small water fountains and needs to be calculated as accurately as possible.
Depending on their height water tank walls can be made out of bricks, breeze blocks or ready-made concrete poured on site, as long as the casing provides for suitable water tightness. They can also be made using metal sections and plates or dug out of the ground and lined with a synthetic, pitch-based, clay or plastic material.
Water tanks that protrude above ground level should be suitably strengthened to prevent any structural failure of the walls such as cracks, chips or breakage, that might lead to the installation being left inoperative until it is repaired or, in the worst case, cause other damage if parts of the wall are sprayed by the water jets falling outside the basin, etc. It is always a good idea to entrust the security of your water tank to a specialist building contractor.
The purpose of the pumping equipment is to enable the water to circulate at the required pressure through the various circuits of the water feature. This task can generally be performed in each specific case by water pumps of varying types, sizes and quality. All water pumps used for whatever purpose should endeavor to ensure that power consumption is kept to a minimum. This characteristic, together with the manufacturer's warranty of the pump's quality, means that in the long run, installation operating costs will be minimal. The working efficiency of a pump in any specific installation depends not only on the quality of its design and build but also, very significantly, on it operating free of any cavitation problems and within its optimal operating range.
Generally, for water feature fountains, submergible pumps and 'dry-well' pumps are used. Submergible pumps have the advantage that they do not call for any additional building such as a pump room or suction chamber, they do not need a suction line and also, because they can be installed within the actual fountain, piping lengths are kept to a minimum. They require underwater electric wiring and, at equal load and flow rates, the initial outlay is greater than for a 'dry-well' pump of equivalent characteristics. Choosing the type of water pump – submergible or not, is a question of economics, where one must decide on the most recommendable option given the specific conditions of each installation, market availability and the investor's preference.
The following days we´ll continue talking about the components of architectural fountains such as the functions of pump rooms, the water feed to the architectural fountain, elements necessary to water discharge in the water feature fountain and the right water treatment in an architectural fountain. We´ll approach all of this in the next Post (Part 2 of 3) of our technical Blog.