South Africa's drought-stricken city of Cape Town says police and military would help secure some 200 water collection sites if authorities must turn off most taps on what they call "Day Zero," a date currently projected to fall in the first half of April.

The city plans to open a disaster operations center Monday to prepare for the possible tap closure that it says would have a catastrophic impact on South Africa's second-biggest city. Cape Town says hospitals, key economic areas and densely populated areas with a higher risk of disease would be exempt from a tap cut-off.

City authorities say residents can avoid "Day Zero," slated for April 12, by each using no more than 50 liters (13 gallons) daily until alternative sources of water are arranged.