The Bangkok Communicable Disease Committee has decided to ban powder smearing and foam parties during the Songkran festival next month.
The Bangkok Metropolitan Administration said that Songkran celebrations could go ahead, but all related activities must follow the rules and regulations.
Traditional water sprinkling is allowed, but alcohol consumption in organising venues is not.
Population density in these venues is limited to one person per four square metres, and participants are required to wear face masks at all times, said a BMA official.
Water splashing, powder smearing and foam parties are prohibited in roads and other public areas, he added.
Families can take part in activities, such as pouring water on the hands of the elderly, but wearing a face mask remains compulsory.
Earlier, business operators along Khao San Road in Bangkok had objected to the ban on water fights, saying they will lose income.