Johannesburg Water say roughly 10,000 Johannesburg residents will be without water on Sunday.
The outage will affect some customers linked to the Illovo reservoir and supply tower.
Residents could awake on Sunday morning to dry taps as the emergency shutdown will be implemented from midnight on 20 October.
Technicians will be conducting repairs to a 600mm main water pipe near the corner of Katherine and Pretoria Roads in Sandown.
Johannesburg Water have not stated how long the shutdown will last or given an estimated time of restoration.
The suburbs affected will be:
Meanwhile, the Gauteng Department of Water and Sanitation (DWS) issued a warning encouraging residents to use water sparingly.
The DWS said the Vaal Dam is currently at 39.5% of its full storage capacity, down from 77.5% at the same time last year.
ALSO READ: Vaal Dam levels continue to drop, now below 40%
The city of currently under Level 1 water restrictions with a R5,000 fine applicable to residents caught watering their lawns and gardens between 6am and 6pm.
Residents are also not allowed to wash their driveways, patios or hard outdoor surfaces using a house pipe or risk the same penalty.
The six-moth shutdown of the Lesotho Highlands Water Project began on 1 October.
Pumping of water from two dams in Lesotho into the Integrated Vaal Tiver System (IVRS), which feeds Gauteng, was stopped in order to contact necessary maintenance.
The Vaal Dam is one of 14 dams that make up the IVRS and is the primary feeder for Rand Water, who will draw from the Sterkfontein Dam should the Vaal drop below 18%.
NOW READ: Lesotho Highlands water shutdown kicks off on 1 October: Here’s what to expect
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