WATCH: Dead fish sparks Umgeni River contamination probe

The investigation comes after videos were shared online, showing dead fish floating in murky water at Durban's Blue Lagoon.

The city has urged locals to not consume or collect the dead marine life.

Arrangements have also been made to remove the fish and mitigate the impact on the local environment.

"We believe that it's now high time for the government to make good on the constitution and start fixing the critical sewerage infrastructure that needs to be fixed,” says Heinz de Boe, who is the DA's KZN spokesperson on Environmental Affairs.

 READ MORE: eThekwini lambasted for 'devastating' Isipingo Lagoon fish disaster

“It's estimated that we need at least R4 billion in KZN to fix the infrastructure damaged by the recent floods. But this is not a new issue. Provincial and National governments have allowed the infrastructure to deteriorate to the point where it's now critically failing.

“No longer is E.coli measured in hundreds of units, it's now measured in millions of units. With the Umgeni River suffering heavily with pollution.”

Meanwhile, eThekwini's closed 13 beaches in Durban because of high levels of E.coli.