Faecal sludge is a fluid mixture of untreated and partially treated sewage solids, liquids and sludge of human or domestic origin. In other words, faecal sludge is sludge from onsite sanitation systems that is a combination of raw primary sludge and anaerobically digested sludge. The physical , chemical and biological qualities of faecal sludge are influenced by the duration of storage, temperature , soil condition, and intrusion of groundwater or surface –water in septic tanks or pits, performance of septic tanks, and tanks-emptying technology and pattern.
