The City of Johannesburg’s wastewater treatment system is deteriorating significantly, with half of its plants in critical condition according to the 2025 Green Drop Report. Released on 31 March by the Department of Water and Sanitation, the report gives the metro an overall score of 48.8%, down from 91% in 2011. Failing plants are releasing poorly treated sewage into rivers, posing risks to public health and the environment.
The 2025 Green Drop Report assesses wastewater management across South Africa, scoring authorities on operational capacity, environmental performance and compliance. Johannesburg’s score has fallen steadily: 86% in 2013, 73% in 2021, and now 48.8% in the poor performance category. Scores below 31% trigger national intervention.
Of the city’s six treatment works—Northern Works, Olifantsvlei, Ennerdale, Driefontein, Bushkoppies and Goudkoppies—three are now in critical condition at 30%, down sharply from 2021 levels of 77%, 73% and 65%. The others achieved good or average results. Effluent and sludge compliance is rated poor, leading the Department of Water and Sanitation to issue five directives, two notices and refer five criminal cases to prosecutors.
Persistent vandalism, inadequate maintenance and procurement delays—sometimes linked to political interference—have crippled infrastructure across the 12,812km sewer network. Plants built for 1.1 billion litres daily now reliably treat only 945 million, with some like Ennerdale over 200% capacity.
Dr Ferrial Adam of WaterCAN said: “These results confirm what communities have been saying for years. The crisis is not new. What is new is the continued failure to act.” Johannesburg Water’s Motale Selesho acknowledged the need for “urgent and sustained improvement,” stating the city is committed to corrective measures with the department.
The utility’s 2025/26 plan allocates R214.1 million for upgrades and R317.6 million for blockages and pipes, but faces backlogs exceeding R20 billion.
