Marine Water Quality in Hong Kong in 2017 & 2019


To protect the marine environment of Hong Kong, the Environmental Protection Department (EPD) has been implementing a comprehensive marine water quality monitoring programme since 1986.

The aims and objectives of the programme are to: • evaluate the state of marine waters; • monitor long-term changes in water quality; • provide a scientific basis for planning water pollution control strategies; and • assess the compliance with the key statutory Water Quality Objectives (WQOs).

Every month, the EPD monitors the marine water quality at 76 open waters monitoring stations and collects and examines phytoplankton samples from 25 of these stations. We also monitor the water quality of 18 sheltered waters monitoring stations located at 14 typhoon shelters, three sheltered anchorages and the Government Dockyard bimonthly. In addition, sediment samples are collected and analyzed at 60 stations, including 45 in open waters and 15 in sheltered waters, twice a year


Updated version (2019) :

In 2019, the document shows that the North Point waters actually have close to the optimum temperature, pH, phytoplankton density, oxygen, and nitrogen content for the water filtration effect of local HK oysters. The point of focus is 'Junk Bay WCZ'. Red tides are not very frequent in the area. The amount of dissolved oxygen is showing an increasing trend. E-coli is showing a downward trend. Thus, oyster growth is expected to be smooth.