Fountain Design Process & Guidelines
For your convenience, 1 cu. ft. of water - 62.4 lbs. (28.3 Kgs.) and 7.48 U.S. Gallons (28.3 Liters) - 1 Meter = 3.28 Ft.

Step 1 : Determine the effect desired
  Consider the size of the effect in relation to the size of the pool, the site and surroundings. Most fountain pools are 18" deep, so be sure to provide a sufficient volume of water to produce the effect satisfactory.

Step 2 : Define size, shape & depth of your pool
This planning should involve such factors as the pool configuration most suitable for the site, as well as pool location and orientation, the materials you wish to use, the available water supply, etc.

Step 3 : Choose the proper pump and piping
  The nature of the effect, the elevations, piping distances, fittings and valves will determine the size of the pump required. Large fountains normally use centrifugal turbines or flooded end pumps, while less expensive, easier to install submersible pumps are specified for smaller effects.
For computing pressure, 2.3 ft of head is equal to one PSI; 1 Meter of head to 1.4 PSI. Piping Size: If 100' of pipe is required to reach pool center, 100 GPM requires a 3" pipe; 200 GPM a 4" pipe; and 300 GPM, a 6" pipe. (For flow of 5 FPS). A 3" pipe provides a flow of 5 FPS maximum, 4" or larger pipe, 10 FPS maximum. Gravity Return Piping is usually sized for flow of 2 FPS or less. Sizing is critical, and unusually long runs or changes in elevation must also be considered. Return Piping : 3" diameter or less; 5 FPS. 4" or more, 7 FPS maximum. Gravity Drains and Overflows : 5 FPS maximum.

Step 4 : Choose your filters
  Water clarity and condition is important in all fountains, and most of them use a small recirculating pump and sand filters, with skimmers or floor drains returning with water to the filters. This action can be independent of the water effect. A high rate sand filter area for each 1000 cubic feet of pool area, is normally
recommended for larger fountains, with the filter supplied by an independent pump. For filters 30" in dia. or less, this is usually included. Many smaller fountain rely upon the pump filter screen for water clarity, and are simply drained when necessary. When chemical addition is desirable, metering pumps with hypochlorite systems may be used. A reliable pool service to monitor and maintain water clarity and chemistry is often the simplest answer to water treatment concerns.

Step 5 : Define and locate plumbing for pump and filter systems; locate sensors, lights and junction boxes to be in the pool
Pumping systems often need antivortex plates for inlet lines, shut-off and flow control valves, and strainers. Filter systems include antivortex plates, inlet fittings, skimmers and vacuum fittings. The electrical systems normally include underwater junction boxes, low water cut-off sensors, water make-up and wind sensors, times and lighting fixtures. 

Step 6 : Determine your lighting requirements
Lighting may provide overall pool lighting, illuminate key elements and create visual contrast between elements. Underwater units should be located about 2" below the water surface, and may up-light jets, spray rings, cascades, etc. Flood lights accent above-water elements or provide safe area illumination.  

Step 7 : Define the controls
Controls may include such elements as timers for pumping, lighting and filtering operations, as well as motor starters for the pump, water make-up, low water cut-offs and various valves. Weigh the merits of both electro-mechanical and micro-processor controls in this respect. 

Step 8 : Consolidating & locating the equipment
Simple fountains with submersible pumps require a small panel mounted in any suitable location. Larger water effects, pumps, timers, microprocessor controls, electrical panels, fuses, filtration and water conditioning elements and other controls are consolidated and installed in a small building or vault, or on a fenced pad. Local building codes govern location, ventilation, access, etc.
Systems
Once the basic fountain design is settled, systems to produce and maintain the display must be worked out. These systems include: 1. The Pumping Systems, with the jets or water diffusion plates to create the effect; plus the pump water inlet and the required valves and plumbing. 2. The Filtration System, to keep the water invitingly clean with a re circulating pump, skimmer, vacuum lines, valves and plumbing. (Here elements to provide chemical water treatment are often included). 3. The Electrical Systems, with sensors to maintain water levels and shut down electrical equipment when water levels are inadequate. Sensors can also shut down or reduce the size of water effects in high winds. Mechanical or microprocessor controls, timers, motor starters, contractors and underwater lighting units are also included.

The size of a pool or reservoir and the size of its water effect are interrelated. The pool must contain a sufficient volume of water to meet the requirements of the effect, and be large enough to contain the splash or wave action it produces. This splash pattern will be approximately as wide as its height, so the pool's minimum diameter should be twice the height of the effect. In addition, jets, fountains and waterfalls require that both flow rates and pressures be adequate to produce the visual effect desired.
Waterfalls have unique flow requirements. A weir depth of 1/4" requires a flow of 10 GPM per linear foot of weir. A depth of 1/2" need 20 GPM; and a depth of 3/4" , 30 GPM. The total height of a weir should not exceed the distance from its base to the pool's edge.

Large Fountain Design Layout

A Large Fountain ...

Pump Section - Water is supplied to the pool via a main line and inlet (1), which is controlled by a gate valve for inital filling of the pool. A centrifugal end pump (2) recirculates water through a butterfly valve (3) for adjustment and a jet (4). Water from the jet is contained in the pool and returned to the pump via an anti-vortex plate (5), butterfly isolation valve (6), and strainer (7), for removal of coarse material and protection of the pump.

Filter Section - Water is filtered by a sand filter (8), which includes a self-priming pump independent from the main fountain group. Water is returned through a gate isolation valve (9) through adjustable inlets (10), which can be directed to create turbulence in desired areas. Water is returned to the filters via an anti-vortex plate (11), surface skimmer (12), and a vacuum fitting (13); which are connected to a manifold (14). These lines each have isolation gate valves. The manifold is connected to the strainer on a small self-priming pump which recirculates the water from the pool through the filter. Chemical addition is accomplished by use of a small metering pump (15) and tank to supply hypochlorite solution. An overflow drain (16) is set to eliminate rainwater, etc., to prevent overflow. The upper section can be unscrewed to completely drain the pool.

Electrical Control Section - An electric water makeup control replaces water lost to evaporation, splashing, etc. This sensor and control actuate a solenoid valve (17) on the main water line to maintain water level and cuts off electrical power to lighting fixtures if they are not immersed. A wind control (19) monitors wind conditions and can shut down or reduce the flow to the jet at preset wind conditions. The underwater lighting fixture (20) is a base mounted unti connected to an underwater junction box (21) by underwater cable. The junction box is conduit-connected to the control box, and completely potted to prevent leakage. The light is controlled by a timer or sequencer. The main control box (22) houses the timers, light controls, water makeup and wind controls. In addition, it is the center for power distribution to various components and contains circuit breakers, fuses, motor starters, etc.
This diagram illustrates the various circuits and components commonly used in a large fountain, including a centrifugal flooded end pump, a filtration and water treatment system, various sensors, underwater lighting and electrical controls.

Fountain Design - Engineering and Conversion Data