Could it be the first city in the world to run out of water? Maybe.

South Africa's Cape Town, considered as one of the world's iconic tourist destinations, may run out of water by 22 April as it's the worst drought for the city in a century. This risks can force residents to join queues for emergency rations.

"Day Zero" the day where taps are about to run dry and city authorities are speeding to build desalination plants and drill underground boreholes to gain water. At a trial water collection site, the city may introduce people queue between metal fences waiting to fill up containers from standpipes.

It has been officially said that a maximum of 25 litres of water will be provided per person and per day. Authorities want to reduce the city's consumption to 500 million litres a day which is half the amount used two years ago.

"Everyone is taking as many steps and measures that they possibly can to try and make sure we don't reach Day Zero," said Gabrielle Bolton, spokeswoman for the five-star Belmond Mount Nelson hotel. City officials said dam levels dropped below 30 percent in the first week of the new year with only about 19.7 percent of that water considered usable.

Residents will have to queue for water only when dams reach 13.5 percent.