The filtration system consists of a flow regulating tank, ascending flow pre-filter, and 15’ X 20’, descending flow, main filter. The system can run continuously at a flow rate of 7 liters per minute.
The main filter consists of a concrete tank filled with layers of sand and gravel to a height of one meter. A biological layer naturally forms on the top layer of sand and contains microbes that will predate on harmful bacteria. A diffuser ensures that incoming water does not agitate the biolayer. The effluent pipe is raised to a hight above the top sand layer to ensure that the filter matrix remains submerged even if water supply is temporarily cut from the system.
Our team surveyed local alluvial deposits and found material suitable for the filter matrix. Sand and gravel was then sieved into appropriate sizes and washed before being loaded into the filter.
