TalkClimateChange

New Mayor, new issues. Wild Hair!

I guess I would have to be better educated on the water supply issue for London and the specifications for the plant.

Seems strange in a rainy country, but it may be about guaranteed volume and local production as a factor of cost?

I would be interested in learning more.

# start sarcasm

Besides with sea-level rise de-saliniation is not such a horrible plan, perhaps we could build thousands of them and sequestor the rising oceans in old oil wells? Oops full of CO2! OK abandoned coal mines!

As far as a powersource I am very fond my my Bio-fuel 2.0 idea of using the decomposing bodies of Genus Lepus being consumed by enzmes and bacteria to generate a liquifiable gas.

I call it my Wabbit Powered Bio-Weactor. - Elmer Fudd (spokesman)

Sustainable, Natural, Rapidlly reproducing fuel source, the perfect bio-fuel solution.

I am kidding. I actually think seals are a better fuel.

# end sarcasm

Sorry Matt my sarcastic gene is flaring up again

One of the issues as I understand is the fact that a third (or is it 2 thirds - can’t remember) of water in the UK is lost between reservoir and tap as a result of leaky pipes and decrepit infrastructure..

A desalination plant sounds like a quick fix.

A couple of things to consider. London & the South-East is the driest part of the UK. It also houses a fifth of England’s population (10m+). The region also has the highest level of internal and external mitigation.

The pressure therefore is to serve an increasing demand with variable local climate issues - dry winters have been a problem in terms of the water table. The infrastructure is also poor (our Victorian ancestors are spinning in their graves) and is the subject of a very large and expensive capital project to improve this situation.

However, improving the infrastructure won’t solve the supply problematic for Thames Water. There are two solutions proposed: Desalination (which Thames Water can control) or be supplied by another region of the UK (which relies on Government support). As a private regional company, desalination is the logical solution.

On a UK level, we have more than enough rainfall to supply our growing population. The problem is that it doesn’t rain consistently across the country. Some have mooted an idea of a national water grid but that would require considerable time, organisation and expense and be delivered by the UK Government. Can’t see that happening.

A lot of water is lost in leaking pipes worldwide (I got data on Brazil and Egypt… minimum).

It is a major issue that should be addressed.

I remember that the WWF once stated that desalinization should be used when all else have been done. It doesn’t seem it have been done in the UK.

Cleaning the Thames water ? Why not if it is not as dirty as the Seine in France…

Keep up the good work !

Some interesting responses, excellent!

CH, I’m just not sure how we would transport the seals over here? Maybe with a bit of genetic engineering we could get them to swim straight up the Thames and into the desal plant.

A few things. (I should admit that I don’t know what the desal plant output will be).

“On average, over the last five years (2002-2007), household, commercial and industrial water use was 1,718 million litres per day in London. This can be split into 1,212 million litres per day for household and 506 million litres per day for non-household.” (from UK EA).

In 2006, we managed to reduce demand by 176 million litres per day, by appealing to people to reduce their usage.

Despite the fact that London and the South East have less rainfall, actuall the water tables are rising:-

“It is estimated that 70 mega litres of water per day must be pumped out to prevent flooding or damage to London’s infrastructure, sewers and deep tunnels. In 2001 London Underground pumps some 30,000 cubic metres of water daily from its tunnels with approximately 4,500 litres being removed from Victoria Station alone.” This has been going on for some time; I remember reading that in 1991 LUL nearly had to shut down the Northern Line due to the water level.

I don’t know where the water currently goes, but this is interesting considering the Mayor’s power in Transport for London.

It looks like we can save ~250 million litres per day through simple efficiency measures and using the water pumped from the underground. Combine this with the 30-40% leakage loss, and I for one start wondering why we need a desal plant, despite your good points, JCL.

But then, stop the leaks, and a significant number of London’s trees will die. And I do like living in such a green city…

From : http://www.guardian.co.uk/environment/2006/may/24/water.uknews

“The company [Thames Water], which supplies 6.2 million Londoners with water, also argued that a desalination plant providing 140m litres a day of water was essential for the capital’s security”
…
“The problem, said Mr Livingstone, had arisen because of Thames’s mismanagement of its network, which resulted in 915m litres of purified water leaking from its pipes every day.”

The TW argument seems to revolve around a terrorist attack: in the event of a threat to the water supply, the desal plant can come into action. I’ll leave you to ponder the flaws in that argument!

The problem with the “repair the leaking pipes” argument Matt is that the water isn’t lost. As you sort of point out, it returns to the water table or other underground infrastructure such as the tube. The question is where does the water go once pumped out of the underground? Back to the water table is the most probable answer.

So while the leaking infrastructure isn’t particularly efficient, its consequences are mostly about delivery to customers and inefficient operation costs to Thames Water.

The problems of increased demand and water table levels will not go away if the infrastructure was 100% efficient. Drought and increased demand will affect the water table. A desalination plant is a sensible contingency plan for Thames Water alongside encouraging efficiency of usage and improving the infrastructure.

“The problems of increased demand and water table levels will not go away if the infrastructure was 100% efficient.”

Arguably not, but considering 915 million litres of already purified water ‘go missing’, and the £200M desal plant is expected to provide 140 million litres, the money could be wiser spent elsewhere.

The problem of leakage remains: London uses 1718. It loses 915, so 2633 total is required. That means 35% of the desal plant production will also be wasted.

Since it will only provide 5% of London’s demand in the first place, do you not agree that the £200M build cost plus running costs could be better spent?

Ken was right to call for a review. How much tax-payer money will be spent on this plant? Will we end up paying for it twice, considering we are well on our way to water metering (an ideal opportunity to put the price up)?