The Special Investigating Unit (SIU) is investigating more than 30 cases linked to water tanker corruption following the launch of the Water Sector Anti-Corruption Forum in March.
Water and Sanitation Minister Pemmy Majodina revealed the figures while delivering the opening address at the Water Institute of Southern Africa's Biennial Conference and Exhibition in Cape Town.
Majodina acknowledged that criminal syndicates, commonly referred to as the "water mafia", continue to undermine the country's water supply systems but said government has intensified efforts to dismantle their operations.
She explained that those involved in the alleged criminal networks are able to monitor and direct the movement of water tankers, controlling where they are deployed and when they operate.
The minister said the Water Sector Anti-Corruption Forum, established in partnership with the SIU, has already resulted in more than 30 active investigations.
She added that the Presidential Water Committee also includes a water security and intelligence component tasked with tracking and disrupting the activities of the so-called water mafia.
Majodina took a firm stance against the criminal networks, saying they have no regard for her efforts to root out corruption, adding that the matter would ultimately be settled through the courts.
The minister also highlighted the scale of South Africa's water infrastructure crisis, saying an estimated R400 billion is needed to repair ageing infrastructure, fix leaks, replace burst pipes and address other maintenance backlogs.
She acknowledged that neither national government nor municipalities have the financial resources to meet those costs and called on the private sector to partner with government to help fund critical water infrastructure projects.