Cape Town's Deputy Mayor Ian Neilson says Day Zero has been pushed back partly due to the slowing decline of dam levels.
The City of Cape Town last week announced that Day Zero would be moved to 4 June.
Neilson says the latest Day Zero projection has not taken into account all the water from the Palmiet-Kogelberg dam near Grabouw, which will feed into the Cape's municipal supply.
The City has secured 67 million litres a day, for 60 days from the Palmiet-Kogelberg dam.
There are concerns that announcing the changed Day Zero projections will cause residents to slack off on water-saving efforts.
Neilson says that punitive water tariffs, the pressure reduction programme and other measures will help keep consumption down.
He says city officials have decided not to drop the phrase 'Day Zero' for now.
Also read: City of Cape Town: Day Zero moves to 4 June
This phrase has been so entrenched in public discourse that we need to keep it for the moment.— Ian Neilson, Deputy mayor in the City of Cape Town
The slowing of the drop of the dam means that the projection pushes further out into the future.— Ian Neilson, Deputy mayor in the City of Cape Town
That is the concern, that people will relax.— Ian Neilson, Deputy mayor in the City of Cape Town
Effort to avoid Day Zero can only be achieved by keeping consumption down.— Ian Neilson, Deputy mayor in the City of Cape Town
Neilson explains the factors which have been taken into consideration to determine the Day Zero projection.
Take a listen to the deputy mayor: