A play pump is a water pump which doubles as a merry go round for children. When children play on the merry go round, they power the pump, bringing clean water up into a storage tank which can be used to feed spigots and other plumping fixtures. The play pump is designed to be very simple and easy to maintain, so that it can be installed in rural areas to ensure a steady supply of safe drinking water. The bulk of such pumps are currently installed in Africa, but they can potentially be installed anywhere in the world.
The design of a play pump is much like that of a windmill. As children play on the merry go round, the pumping system activates. The storage tank is designed on a gravity feed system, so that no additional power is needed; when someone opens a spigot, the pressure of the water in the tank pushes water out. All of the components are ideally cheap and easily replaceable, and the design is simple enough that someone with basic mechanical abilities can care for the play pump with ease.
In addition to providing a supply of clean water and a place for children to play, a play pump can also be used for public health messages. The sides of the storage tank are an ideal medium for various public service announcements, and they can also be leased as billboards to finance the initial expense of the play pump.
Access to safe drinking water is a major issue in the developing world, which makes solutions like the play pump especially vital. Charity organizations can install such pumps as part of their mission to help villages sustain themselves, and villages can also opt to band together to buy a play pump. Since the design is meant to be shared, a single play pump located in the center of a village can meet the water needs of the residents with relative ease.
In order for a play pump to be effective, the underlying water table needs to be safe from contamination. While a play pump can potentially be linked to a river, for example, most development agencies try to avoid using rivers as sources of water, due to risks about pathogens and toxins which may be carried downstream. Theoretically, a play pump could be linked to a water purification and treatment system to address the issue of water safety, but more commonly, the groundwater is simply periodically tested for safety, because water filtration is too expensive and complex for many villages.