Characterization of Faecal Sludge from Pit Latrines to Guide Management Solutions in Cape Coast, Ghana

Abstract

This study characterised faecal sludge from public ventilated improved pit (VIP) latrines in Cape Coast to assess their potential impact on the environment and to guide the selection of appropriate management solutions. The paper also estimates the amount of beneficial resources wasted due to the lack of a faecal sludge (FS) treatment facility. The study employed a quantitative design involving laboratory analysis of FS sampled from 13 purposively sampled VIP latrines in Cape Coast, Ghana. Sampling activities were carried out in January and February (dry season) and September and October (wet season) of 2015. Samples of unhardened pit latrine sludge were collected from all 13 pit latrines for quality assessment. Physicochemical parameters (moisture content, COD, BOD5, total solids and total volatile solids) of homogenous samples from the surface, middle and bottom of pit contents were analysed following standard procedures. Apart from total solids, all other parameters decreased with the depth of sampling and the differences were statistically significant (p<.01). Seasonal variation in faecal sludge characteristics was not significant except for BOD5. A high COD: BOD5 (3.8-4.5:1) shows faecal sludge that is characterised by slowly degradable organic matter. Even though the FS at the bottom of the pits was found to be the most stabilized, its characteristic parameters indicate that discharging it into the environment without any further treatment would pose a significant threat to public health.  The characteristics suggest that co-composting would be the most appropriate option for treating the FS and also underscore the fact that the VIP latrine technology is not suitable for use as a public toilet.