Wastewater Collection and Transportation through Drainage Network- a Potential Threat to Biodiversity & Local Eco-system in Zanzibar Stone-town & Surroundings

Wastewater effluents discharged into coastal waters around Zanzibar's Stone Town pose significant threats to biodiversity and public health, revealing alarmingly high levels of contamination. A cross-sectional study identified that impervious drains, out-pour sites, and afternoon samples exhibited the highest bacterial loads, predominantly gram-negative Enterobacteriaceae, including Vibrio cholerae. Physicochemical analysis showed lower dissolved oxygen (DO) in impervious drains and elevated turbidity in mornings, with one drain exhibiting exceptionally high levels. Groundwater near pervious drains also exceeded WHO coliform guidelines. The findings underscore the urgent need for wastewater treatment strategies to mitigate ecological and health risks in this UNESCO World Heritage Site.

M. Abubakar, Z., R. Rabia, A., M. Ussi, A., A. Bakar, M., & A. Ali, R. (2018). Wastewater Collection and Transportation through Drainage Network- a Potential Threat to Biodiversity & Local Eco-system in Zanzibar Stone-town & Surroundings. International Journal of Pathogen Research, 1–13. https://doi.org/10.9734/ijpr/2018/v1i11210