Efficacy Assessment of Decentralized Wastewater Treatment Systems in treating Faecal Sludge within Dar es Salaam City

Mwingira Catherine^* & Alexander Augustina

Abstract

Dar es Salaam Water and Sewerage Authority (DAWASA) considers DEWATS as effective system for faecal sludge management especially from unplanned settlements. No study has been done in Tanzania to assess the treatment efficiency, adoptability and sustainability of the systems. That being the case, this study aimed at assessing the treatment efficiency of the Decentralized Treatment Systems installed within the city. Kigamboni and Mburahati DEWATS were selected as case study areas for the study whereby, quantitative method was used for data collection. The collected results showed that most of the physical parameters were within the allowable range specified by Tanzanian Standards for municipal wastewater discharge (TZS 860:2006). Nitrate and Phosphate levels were within the allowable range at both treatment plants. The BOD₅ and COD for Kigamboni DEWATS were four times higher than the maximum allowable safe limit for each. Both Kigamboni and Mburahati DEWATS failed to lower the coliform levels of faecal sludge to meet the maximum allowable discharge standard (10,000 cfu/100 ml) by having the effluent quality of 115,000 cfu/ 100 ml and 22,875,000 cfu/100 ml respectively. Addition of dosing chamber between the gravel filter and polishing dosed at 6mg/l of chlorine remediated the state.

Keywords

decentralized wastewater treatment systems (DEWATS); sanitation; faecal sludge

Cite This Article

Catherine, M., Augustina, A. (2022). Efficacy Assessment of Decentralized Wastewater Treatment Systems in treating Faecal Sludge within Dar es Salaam City. International Journal of Scientific Advances (IJSCIA), Volume 3| Issue 5: Sep-Oct 2022, Pages 782-788, URL: https://www.ijscia.com/wp-content/uploads/2022/10/Volume3-Issue5-Sep-Oct-No.351-782-788.pdf

Volume 3 | Issue 5: Sep-Oct 2022