Accumulation rates and pathogen concentrations in primary stabilization pond sludges in developing countries are important parameters for adequate sludge management and the safeguarding of public health with sludge reuse in agriculture. An anaerobic pond has been investigated for sludge accumulation rates and helminth egg viability after four years of operation in Burkina Faso. The rate of sludge accumulation was measured at 0.037 m3/capita-year or 2.26 kg dry weight/capita-year. An equation describing vertical distribution of total solids in the accumulated sludge was found to be adequately represented by a regression equation. Influent helminth egg concentrations were reduced on average by 90% in the anaerobic pond effluent.
Keywords: anaerobic pond, egg viability, helminth, sahelian climate, sludge accumulation, sludge distribution