NI Water engineers have been dispatched to a burst pipe in the Ballyclare area.
The Times understands approximately 490 properties are currently without a water supply.
Homes in the BT39 and BT42 areas have been affected.
A Northern Ireland Water spokesperson said: “Customers may experience a loss of water supply or a drop in pressure when the work is being carried out. We are working to fix the problem as soon as possible.
“Discoloured water can occur when the mains are disturbed. This can happen when there has been an interruption to supply following a burst main and the operational activity associated with the repair.
“The discolouration will be short-lived, and running the tap for a while should help clear it from the system.”
The estimated restoration time is 9pm tonight.
Meanwhile, some homes may be experiencing a loss of water supply due to scheduled maintenance in the Parkgate and Ballyclare areas.
The work is due to be completed by 5pm today.