Faecal sludge (FS) management is a challenging problem in low-income countries where large parts of
the urban population rely on onsite sanitation systems. The design of treatment plants relies on accurate
knowledge of FS characteristics, but this information is lacking. The goal of this study, conducted
between December 2010 and September 2011, was to determine physical and chemical characteristics of
raw FS from collection and transport trucks in 5 discharge sites in Ouagadougou. Over 100 samples
directly collected during truck discharge were analysed. Analyses included suspended solids, volatile
suspended solids, total solids, total volatile solids, sludge volume index, chemical oxygen demand,
biological oxygen demand, and heavy metals. The FS characteristics were highly variable, but had
similar characteristics for FS collected during the dry and rainy seasons and at different discharge sites.
The type of onsite system had an influence on FS characteristics.