Greenpeace East Asia recently revealed that the largest drinking water reservoirs in our FreshWater Watch location, Hong Kong, have high concentrations of perfluorinated chemicals (PFCs), carcinogenics used in industrial products such as waterproof materials, fire-fighting foams and metal plating.
Plover Cove, High island and Tai Lam Reservoirs are fed by the Dongjiang River in the Guangdong region contained as much as 15.4 nanograms of PFCs per litre of water. For comparison, reservoirs that harvest rainwater exclusively, such as Shek Pik and Shing Mun, were found to 90% less PFCs.
In the wake of the Greenpeace revelations the Hong Kong Water Supplies Department (WSD) carried out its own tests which confirmed the Greenpeace research and also found as many as six times the safety standard for E coli bacteria. Phosphorus, found in fertilisers and animal faeces, was also found at its highest levels in the last 10 years, this has been linked to recent rainfall at 0.057 milligram per litre.
The WSD were not able to say what of the PFCs is, or how they entered the River where 70-80% of Hong Kong’s drinking water is drawn from.
Although there are no agreed acceptable levels of PFCs in drinking water the WSD has said that if it perceives a risk to human health they will take measures to filter out the PFCs.
The WSD visited sites including pumping stations and the river, and Department of Water Resources in the Guangdong region subsequently pledged to restrict PFC use in factories, although it did not give any further details.
The knowledge gap on the health of freshwater ecosystems around the world is well known, and citizen science could be key to completing the picture on the health of waterbodies, pollution sources, effects of weather events and pollutants.
This is the second incident in 6 months that has required Hong Kong to scrutinize its water management policy and question the best ways to operate, with July bringing the discovery of aging pipework adding lead into Hong Kong’s drinking water. It is becoming evident that our freshwater research in Hong Kong is becoming more important than ever.
Lead FreshWater Watch Hong Kong project scientists: Prof. Kin-Ching Ho & Dr. Fred Lee, School of Science and Technology, The Open University of Hong Kong