Residents of Omokoroa, Wharawhara and Minden are being asked to cut their water use to avoid water restrictions.
Western Bay of Plenty District Council's utilities manager Kelvin Hill said those central areas were the only ones affected - eastern and western areas were fine.
Hill said the dry spell had created steadily growing demand and the central zone's water supply systems would not be able to keep pace unless water use was reduced.
"We are urging consumers to please be more conservative with use. Failure to do so will result in water restrictions being put in force."
A sprinkler ban has been in force across Tauranga City since Friday.
