End of summer: Water at 23 beaches, including Repulse Bay, has been rated 'good' for this weekend.

The Environmental Protection Department has rated water quality at 23 beaches 'good' and 10 'fair' for this weekend.

Compared with last week's gradings, Cheung Chau Tung Wan Beach has been downgraded from 'good' to 'fair'.

The department said the changes in grading 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.

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.

For updates on beach water quality click here or call the beach hotline 2511 6666.