The Lower 9th Ward and parts of the Upper 9th Ward are under a boil-order until further notice, the Sewerage and Water Board said.
Officials made the announcement Monday morning, which affects all of the Lower 9th Ward and parts of St. Claude, the Bywater, and the Florida and Desire areas.
Crews have stabilized pressure, and the Sewerage and Water Board is investigating the cause for the drop in water pressure.
The advisory does not affect New Orleans East and other parts of the east bank of Orleans Parish.
It only applies to households and businesses east of Almonaster Boulevard to the Industrial Canal and people in the Lower 9th Ward.
Residents in the affected areas are advised not to consume tap water until the advisory is lifted.
Use bottled or boiled water to drink, cook, clean food or brush teeth.
Those with compromised immune systems should also use safe water to wash hands, shower or bathe.
The advisory will remain in place until tests show the water is safe for use.
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