Mid-April 2018 could be the time, that four million people in South Africa run out of water. The government says Cape Town's largest water reservoir is at dangerously low levels. A rising population, climate change and drought that's lasted more than two years have taken their toll on water supplies in South Africa's second largest city. And as Melanie Rice reports, the so-called 'Day Zero' is fast approaching. We are joined by Dr. Anthony Turton, Environmental Advisor and Professor at the Centre for Environmental Management, University of Free State, from Bloemfontein in South Africa.