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will obviously encounter serious and arduous challenges. Under these
circumstances, we should first understand China‘s national conditions and drinking
water safety problems in a scientific and down-to-earth way, and then try to finalize
the new standard step by step and from one area to another. In this way, the
implementation of this new standard can be effective.
Improved drinking water quality standard will certainly have bearing on the standards
of source water quality and drainage area water quality, especially on the risk
evaluation and treatment of emergencies related to water quality. Although incidents
concerning water quality occurred frequently in China, we have no special risk
evaluation standard. Actually, risk evaluation of drinking water quality incidents not
only should be based on regulated standard, but should take potential danger and
exposure period into consideration. The quantity of pollutants and the time slot
people are exposed to them should be taken into account and dealt with according to
the actual situation. A simple solution merely based on strict water quality standard
concerning water quality incidents will certainly incur social disturbance and financial
loss. All in all, our imminent task is to build up national and local risk evaluation
standards, applicable to water quality incidents and in accordance with China‘s
current situations.
Drinking Water Disposal Technique
The approaches of water supply and disposal may vary in different areas of China;
however, the basic technique is the traditional mode—coagulation, sedimentation,
filtration and disinfection. All previous projects have covered the study of preceding
disposal units such as intensified coagulation, pre-oxygenation and pre-adsorption,
and depth purification units such as ultrafiltration and reverse osmosis. But only a
small part of the study results has been turned into practical technique. In face of
water quality incidents, the regular practice is to adopt temporary measures such as
cutting off water supply and spreading activated carbon, which not only cause trouble
to the people but incur huge financial losses. Given the serious pollution of water
sources and frequent emergencies, we should work out a set of technique schemes
and countermeasures conforming to China‘s national conditions.
The international community has adopted activating aluminum oxide, particle or
powder activated carbon, depth oxygenation and anti-osmotic separation technology
to deal with trace toxicants such as heavy metal and organic chemicals in drinking
water. In some circumstance, China will also incorporate modern depth disposal
technology into our normal flow. Although this is going to require more financial input
and running cost, it still pays, compared with the huge economic losses and terrible
impact on people‘s life incurred by water quality problems and emergencies. In
addition, the development of water quality protection technology with respect to
water acquisition sources and alternate emergency technology in small- and medium
sized water works are all effective methods in accordance with China‘s current
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