The Environmental Protection Department has rated water quality at 18 beaches 'good', and 15 'fair' for this weekend.

Compared with last week's gradings, Kiu Tsui Beach was upgraded from 'fair' to 'good, and Lower Cheung Sha Beach was downgraded from 'good' to 'fair'.

Seven gazetted beaches - Anglers', Approach, Ting Kau, Casam, Gemini, Hoi Mei Wan and Lido - are closed to swimmers year-round because of poor water quality.

Many beaches are likely to be more polluted than their grades suggest during and after periods of heavy rain. Bathers should avoid swimming at beaches for up to three days after a storm or heavy rainfall.