The Environmental Protection Department has rated water quality at 24 beaches 'good' for this weekend, with eight more 'fair' and one 'poor'.

Compared with last week, water quality at Stanley Main Beach has been upgraded from fair to good, and Ma Wan Tung Wan Beach has been upgraded from very poor to poor.

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 heavy rain. Bathers should avoid swimming at beaches for up to three days after a storm or heavy rainfall.