The water authority has warned Pattaya residents to be frugal in their use of tap water, because the water in the city reservoirs has fallen to the minimum retention level.
The warning was posted on the Pattaya Provincial Waterworks Authority Facebook page on Thursday.
The PWA asked people to make wise use of the supply of water.
Pattaya relies on raw water from five reservoirs feeding a treatment plant for the city. The combined amount of water available is 8 million cubic metres, or only 20% of capacity.
PWA Pattaya office chief Chaithas Eedsaeng said the supply is at the minimum capacity for retention needed to avoid damage to the reservoirs.
The agency had decided to reduce the total amount of tap water distributed to customers every day, to 150,000 million cubic metres from 200,000, to slow the reduction of the water level in the reservoirs.
It was also supplying water to households only on alternate days, but customers complained on social media that they were not getting it when they should be.
The PWA office said the Royal Irrigation Department had channelled water from Bang Phra and Nong Pla Lai reservoirs to help Pattaya, and the city also bought raw water from the East Water Group to prevent shortages.
Mr Chaithas said he expected the situation to improve in the second half of this month, when rain is forecast for the eastern region.
The latest three-month forecast of the Meteorological Department is for rainfall in the region to be slightly below average this month.