According to the long-awaited 2014 Blue Drop report the quality of drinking water in South Africa is on the decline.
The release of the report has been delayed since 2015.
The Blue Drop water score has dropped in eight provinces, including top performers Gauteng and the Western Cape.
But the Department of Water and Sanitation says that South Africa's drinking water is still among the world's best.
The 2014 Blue Drop report has become the subject of at least two Promotion of Access to Information Act applications, to force the Department of Water and Sanitation to release the full contents.
On Wednesday the main findings were revealed in Parliament.
Officials blamed budgetary constraints and staffing shortages for delaying this and more recent Blue Drop reports.
Although declining since 2012, Gauteng's water is still the best in the country with a score of 92%, followed by the Western Cape at 89%.
The Blue Drop score has also dropped in KwaZulu-Natal, the Free State, the North West, Limpopo and the Eastern Cape.
Deputy Director General Anil Singh says: “The drinking water that we have in South Africa is amongst the best in the world. So there is no concern or alarm about the decline being so significant that citizens have to be concerned.”
The department has pledged to complete its draft 2016 report by the end of October.