For thousands of years, creative architects have employed formal ponds to provide focus, noise abatement, and evaporative cooling in both public and private gardens.
Although formal ponds were traditionally built of stone, today they can also be built with brick, concrete, or pressure treated wood. A raised perimeter wall can highlight the attractive structural materials and offer visitors a place to sit by the water; a flush edge is easier to build and will make the garden feel more spacious. Simple rectangular shapes with vertical side walls are recommended for ease of waterproofing, but other shapes are possible.
Fish and plants are optional, but a fountain is a virtual necessity. A depth of 10″ to 24″ is sufficient.
Formal ponds can match a more formal architectural design but can be difficult to maintain and expensive to build. Their pumps can clog easily and there is no biological or mechanical filtration. Also, if built from concrete, it can crack.