Our water is safe, professor says, but he can't vouch for your building

After the scare over lead in drinking water elsewhere in Hong Kong, SAI KUNG BUZZ went to ask a professor of environmental engineering about water quality in Sai Kung.

Professor Guanghao Chen of the UST said, “You’ve got to look at the big picture and the small picture.” In Sai Kung and Clearwater Bay we are lucky because our water comes 100 per cent from High Island reservoir. “This is very good quality water.” After treatment by the Water Supplies Department it comes to your building at WHO-approved standard. Then you get to the small picture: How good are the tanks, pipes and fittings in your building?

Guanghao has been working at the UST for 21 years. He is professor of civil and environmental engineering, a fellow of the International Water Association and associate director of the university’s Institute for the Environment. He knows of no problems with water at the university, which checks it regularly.

water2 — How your drinking water is treated before it reaches your building

But problems can occur in individual buildings. “My guess is that a few contractors trying to reduce cost have installed substandard tanks and pipes.” He warned, “Stay calm. Get more information. It’s not an epidemic.”

If you are concerned, have the water in your building tested by a laboratory. The WSD website gives a list of accredited ones. Or hire a professional building surveyor. If substandard water fittings are found, you should act immediately on the advice of the Centre for Health Protection (see the WSD website).

“I drink bottled water,” Guanghao said, “not for safety, for taste”. People with children under six and pregnant and lactating women should use bottled water for drinking and cooking.

Guanghao endorsed the tips given by the WSD:

Each morning run your water taps for one to two minutes before taking water for drinking or cooking. Collect the run-off water for non-consumption uses.
Hot water makes it easier for lead to leach from pipes and fittings into your water, so take drinking water from the cold taps.
Lead in water cannot be removed by boiling.
Most water filters can not remove lead in water. Only those that are certified to the U.S. National Sanitation Foundation 53 standard can do so.
You can drink tap water without boiling providing your building management regularly maintains the water fittings and checks water quality.
Although water filters are not recommended (because they can become breeding grounds for bacteria) if you do use them strictly follow the manufacturer’s maintenance guidelines.
Because activated carbon in water filters may reduce residual chlorine (it’s there to prevent bacteria) in the water, you are advised to boil water before drinking.