The use of a risk assessment tool based on the Sanitation Safety Planning approach for the improvement of O&M procedures of a wastewater treatment plant in Tanzania

The treatment of wastewater and excreta is one of the major challenges in low-income contexts. The urgency of recovery and reuse of nutrients for agriculture come into contrast with the risks for workers, farmers, and communities. This article presents the development of a risk-based methodology adapted from the Sanitation Safety Planning (SSP) and NaWaTech Safety and operation and management (O&M) planning approaches aimed at improving the wastewater treatment plant (WWTP) of the Municipality of Iringa, Tanzania, selected as case study. The proposed approach is an innovative tool to identify and quantify the risk connected to hazardous events: the methodology was applied at the WWTP in order to identify and assess the risks related to the malfunctioning or to some exceptional events that could pose health risks to workers and nearby communities. The process permitted to identify the risk connected to the hazardous events in order to propose additional control measures for events having medium, high, or very high risk level. These additional control measures were aimed at improving current O&M procedures of the WWTP by the use of simple enhancements requiring low investments, as a first step toward the safeguard of the health of workers, farmers, and nearby communities.