O&M improvements for better WWTP performances (Zimbabwe)

The study was done at the Hwange Colliery Company’s (HCC) WWTP in Hwange District, Zimbabwe with the objectives to assess the current performance of HCC WWTP, evaluate the current operation and maintenance practices, and develop an operation and maintenance protocol for HCC WWTP. The results showed that the overall removal efficiencies of TSS was 48% and an increment of 22% for EC in the final effluent. However, HCC WWTP had an average performance of 8% based on the key parameters used to assess the performance of WWTPs. Key parameters of wastewater such as pH, TSS, NO3, PO4, BOD5, Alkalinity, E Coli and COD were 7.29 ± 0.22, 84.8 ± 117.5 mg/L, 136.9 ± 163.6 mg/L, 223.1 ± 67.6 mg/L, 2461 ± 2204 mg/L, 383.0 ± 111.5 mg/L, 382 ± 301cfu/100ml and 10,700 ± 111,667mg/L respectively, which all exceeded the blue and yellow bands of the SI 6 of 2007 Environmental Management Standards of Zimbabwe. The deteriorating infrastructure of the WWTP and the malfunctioning WWTP equipment are clear indicators of poor operation and maintenance practices. It was recommended to put the O&M protocol into practice, which outlines the necessity of technical personnel requirements, protective clothing, training frequency, documentation frequency, and need for a laboratory station, frequency of measuring parameters, data analysis frequency, and types of maintenance frequency.