Montclair and Glen Ridge are now asking people to stop using water unless it's essential.
Offiicials say the leak in the affected pipe has been located and sealed, and they are now working on fully restoring water to all affected within 24 to 48 hours.
It's all following a large water main break in Nutley that affected water service for hundreds of thousands of residents in Essex, Hudson and Passaic Counties.
Massive water main break impacting residents in several New Jersey counties
Bloomfield issued a boil water advisory, and Newark advised residents on Friday that they may experience low water pressure or no water as a result of this incident.
According to a statement from the town of Glen Ridge, repairs to the aqueduct remain ongoing.
"Multiple efforts have been taken to make up for the loss of water from the aqueduct. While these efforts have been successful, the temporary systems remain strained. We need to reduce the demand for water on our system," the town said.
The North Jersey District Water Supply Commission said the problem began Wednesday.
But neighbors told Eyewitness News otherwise.
"On Monday we are woken up in the middle of the night to move our cars, and then it took them," said Bill Wexler.
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