Britain's biggest water company is losing £1.2m a year as a result of thieves who steal metal from its operational sites to sell on to scrap dealers.

Soaring commodity prices are fuelling the underground market for copper, lead and other non-ferrous metals.

Thames Water is using 'SmartWater', a coded-water which invisibly tags its metal - and any thieves who steal it.

Once daubed with the coded water, which shows up only under ultra-violet light, any metal can be traced back to its owner - and the thief or receiver can be linked with the crime scene.


Thames Water is also working with local police and security specialists to install covert traps to capture criminals in the act.

Worst-hit areas in the company's London and Thames Valley region include Aylesbury, Marlow, East Hyde and Bishop Stortford, where earthing cable, lead roofs and even galvanised metal grating have been ripped out of water and sewage works.

Metal thefts across the UK have had major ramifications for transport, communications and utility companies. The cost of a tonne of Copper is now in excess of £6,000.

Bob Collington, Thames Water's director of asset management, said: "Metal theft at our sites costs our customers millions of pounds to put right. We are dealing with this by applying a forensic signature to all our equipment, so anything taken from one of our sites can be traced back. This makes it very difficult for criminals to sell on stolen items without detection.

"Any thieves who target our property face being sprayed with forensic liquid, meaning they will carry evidence of their crime on their skin and clothing wherever they go – it’s a huge risk, for very little gain."

(CD/GK)