Design improvement for pond sand filter

Pond sand filter (PSF), a special small scale filtering device has been used mainly in the coastal parts of Bangladesh to treat the water from rain-fed ponds. It is a manually operated treatment unit, based on the principle of slow sand filtration. Water is pumped up from the pond by a handpump and is poured into a small concrete tank, having more compartments, of which one is the filter chamber filled with the sand. Water passes through the sand filter chamber from where it flows into adjacent storage chamber. A small chamber filled with brick chips acts as a pretreatment unit. The treated water quality depends on the efficiency of the filtration system and also on the raw water quality of the pond. Again, the water quality of the pond depends on design of the pond, the use being made of the pond by people and or livestock, and the runoff into the pond of drainage and wastewater.