Control of lead in drinking water

Lead occurs in raw water abstracted for the public supply system and may also become incorporated at some stage during distribution to the consumer. As previously noted (Section 3.3.5) concentrations in the raw water are generally low. They can, nevertheless, be reduced further during conventional water treatment (Table 6.11). 

Results from 12 treatment plants. Most plants showed a minimal removal of lead. Average raw water lead concentration 0.012 mg dm .  

The major source of high concentrations of lead in drinking water is the dissolution of lead from lead pipes or lead solders used in the distribution system, known as plumbosolvency (Section 3.3.5). In Britain, it is estimated that roughly 7 million households have lead somewhere between the water main and the tap. Many households may thus be exposed to elevated levels of lead in their drinking water (Section 3.3.5). Attention is currently focused on possible remedial actions. 

Pipe lining is being considered but is not a favoured option at present, as there are no proven techniques. Treatment at the tap also has many practical disadvantages, as has flushing of water before use, although the latter is a useful interim measure. 

There is clearly no easy solution to the problem of lead in drinking water. Treatment may eventually prove to be the best option but a better understanding of the chemistry of lead in water will be necessary before success can be reasonably guaranteed. 

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Sheiham I. and P J. Jackson (1981), The scientific basis for control of lead in drinking water by water treatment, Jo r a/ of the Institution of Water Engineers and Scientists, 35(6), 491-515. 

Best Brax lce Quidey on the Control of Lead in Drinking Water... 

The Authors. Best Practice Guide on the Control of Lead in Drinking Water. Edited by Dr Colin Hayes. ISBN 9781843393696. Published by IWA Publishing, London, UK. 

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