DESALINATION CONFLICT

by Michael Smith (Veshengro)

Desalination can provide significant benefits to communities that have depleted or limited access to traditional ground or surface water supplies. However, it can be an extremely costly technology and key challenges include minimising energy consumption and environmental impacts. Two papers at CIWEM’s Annual Conference 2010 will be addressing the issues by examining Adelaide's first desalination plant currently being constructed at Port Stanvac and the proposed Thames Estuary plant.

In 2002, Thames Water began to give serious consideration to building the first municipal desalination plant on the British mainland near the Thames Estuary. Ofwat agreed with Thames Water’s assessment that they had a supply demand deficit under sustained dry conditions and that there was little alternative but to develop a desalination scheme. However Ken Livingstone, then the Mayor of London, challenged the decision. His view was that Thames Water should improve their leakage performance, manage demand and consider less environmentally damaging options for meeting any shortfall, principally wastewater reuse. Dr Graeme K Pearce of Membrane Consultancy Associates Ltd will provide an independent assessment of this conflict, comparing the energy use of treating different sources and examining issues regarding the sustainability of desalination.

In contrast, environmental consultant Mott MacDonald will present a paper looking at how Adelaide’s desalination plant will provide the city with around 25 percent of its water supply needs. The 300 Ml/d desalination plant will be operational by December 2010, preserving the water supply to the city. The paper will explore the environmental and technical issues associated with the project and describe how it was delivered.

Desalination will, I believe, become a very important issue for us in the future.

While it rains a lot in Britain, for some reason we are very susceptible to drought, but this is not so much due to lack of rainfall – though there have been times in the previous years where parts of the year have been drier than usual.

This seems to be changing, once again, though and we seem to – unless it is just a perception – more rain now in the last year or so, than we know what to do with – judging by the floods that occurred in a number of places.

The problem for the South of the country is, however, that the pressure on the traditional sources of drinking water are far too great due to way too many people and businesses clustering in London and the Home Counties.

Desalination could be the answer here and Thames Water should be given the go ahead to build the plant that they have in mind.

In addition to that, however, the first port of call must be repair of the leaky mains which lose us millions of gallons of water annually into the soil.

Water & Environment 2010: CIWEM’s Annual Conference will be held on 28th – 29th April in London. To find out more, including who is speaking and exhibiting, go to http://www.ciwem.org/events/annual_conference.

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