EXPLAINER: This is why parts of Durban will be without water on Thursday Share DURBAN - Parts of Durban will be without water for at least 19 hours on Thursday for Umgeni Water to conduct essential repair work on a scour valve. Umgeni Waterâs Shami Harichunder said aqueducts 3 and 4 in the Nagle System that supplied raw water to Durban Heights Water Works for treatment would be shut down. He said 19 hours have been allocated for this work to be undertaken and completed. "There are four aqueducts in the Nagle System. Two of them (1 and 2) will continue to function while repairs are being undertaken on the other two. However, the impact of the closure of 3 and 4 will be reduced supply of raw water to Durban Heights Water Works, from an average of 550 million litres per day to 380 million litres per day.â