Water quality at 21 beaches will be 'good' this weekend, according to the Environmental Protection Department's latest gradings. Twelve will be 'fair'.

Compared with last week, Lower Cheung Sha, Middle Bay and Shek O Beaches have been upgraded from 'fair' to 'good'.

The changes are generally within the normal range of fluctuation of the bacteriological water quality of the beaches.

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.

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.

For more information visit the department's website, or call 2511 6666.