Aucklanders have failed to save enough water for a second day running.
Watercare says the 409 million litres used yesterday across the region was still above the vital 400m litre limit, even though it was 10m less than Monday.
Watercare said it was doing everything possible to avoid a boil water notice, including increasing capacity at all treatment plants.
"Auckland has demonstrated that we can reduce our water consumption without significant inconvenience. But as the weather improves and the weekend's storms become a distant memory, we run the risk of forgetting the need to reduce water use," said Watercare chief executive Raveen Jaduram.
"The reality is we are still dealing with 100 times more silt at our Ardmore treatment plant. And so we need to remember every day to reduce our water use by 20 litres per person."