The best placement for your water feature is the location that will provide you with the most pleasure. Your water feature should be close enough to be seen, heard and enjoyed. Water can produce a variety of sounds depending upon the layout of the feature. A gurgling brook, the light spray from a fountain head, the splashes from a bathing bird or the crash from a waterfall. Even if the pond is not immediately visible the sound will be there to relax, soothe and act as a drawing feature.
It is also important to consider your water feature from the perspective from inside your home. You probably spend more time inside your home than out in your yard, and if you have a view of the pond from the breakfast nook or your favourite reading chair you can enjoy its beauty at any time and might be privy to a lot of animal activity that you would otherwise miss.
This same idea goes for sound. Your neighbors may not share your views on this but perhaps your idea of heaven is being lulled to sleep by the croaking of frogs. Then, be sure to put the pond close enough to your bedroom window so you have a concert every night. If you don't get along with your neighbors and plan to keep it that way you may want to consider moving the pond a little closer to their bedroom window.
Other determining factors are sunlight, the existing landscape and the elements within it, as well as accessibility of utilities.
Sunlight is very important for growing most water plants and also gives the pond a magical reflective quality. Sometimes a shady location is the only location available for your pond. Do, however, be warned that, if this shade is provided by trees, their falling leaves or needles will become an endless source of debris in your pond. A lot of decaying material is harmful to other life within your pond and should be removed on a regular basis. A little shade is fine but, ideally, for most gardening purposes your pond should have six or more hours of direct sunlight per day. If water lilies are your passion then, the more sun the better.
Another thing to consider is the existing landscape, its architectural style and size, as well as the elements within it. For example, a natural slope may work to your advantage as the basis for a waterfall, cascading steps or a meandering stream. Also consider the existing locations of trees, not only because of their leaves as previously mentioned but because their roots may cause a problem during excavation. They can be cut but you may harm the tree in the process.
The existing soil and site conditions are also very important. The pond should be situated on level terrain. This helps ensure a uniform water level around the entire circumference. Avoid the lowest point in the landscape because of potential run-off and drainage problems. A high water table or very rocky soil may make a raised water feature more feasible than an in-ground pond.
It goes without saying that the style of the water feature should be in harmony with the rest of the landscape and the buildings. A natural shaped pond edged in field stone will look out of place in a formal English rose garden. The size of the water feature must also harmonize with its surroundings. A very large water feature in a small residential yard will be out of scale as would a relatively tiny pond in the middle of a six-acre lot. The size of your pond is ultimately determined by its environment, its purpose, and the amount of money you are prepared to part with.
Is it meant to be the focal point of your yard or do you wish to place it discretely within the landscape where it will provide an element of surprise upon its discovery ? Is it meant mainly for gardening purposes or are you interested solely in the acoustical quality of the water ? The most successful water gardens are those that were thoroughly thought out and planned before the shovel and the wheelbarrow were ever removed from the shed.
Another important item to consider is the accessibility of both water and electricity. Your pond may need to be topped up from time to time and should be within easy reach of your garden hose, unless you are planning to incorporate an automatic filling system which will require some plumbing work. Electricity is needed if you plan on using a recirculating pump or underwater lighting, for example. It is very important that the electrical receptacles be close to the pond (consult your electrician for current regulations regarding minimum distance requirements from electrical outlet to pond). Exposed power cords make an excellent snack for squirrels and raccoons, and, aside from having to replace a gnawed electrical cord, you may even have to deal with a damaged pump. Some cords use a paper wrapping around individual wires which absorbs water, acts as a wick and draws water right into your pump motor. Make sure that your receptacles are properly grounded and GFCI (Ground Fault Circuit Interrupter) protected. Contact your electrician for assistance. Exposed power cords are also dangerous when mowing lawns, and they can be tripped over. Extension cords are not a good idea around the pond.
The last consideration is wind. If you are planning a large spraying fountain, a fleur-de-lis, for example, and wind is a problem in your area, consider either lowering the height of the display or increasing the surface area of the pond. Unless you have an automatic top-up system it is crucial that the water returns to the pond and does not end up in your flower beds. You might want to think of a more sheltered location for a feature of this type.