The contract will see G4S install and maintain CNIguard smart sensoring systems at 33 Sutton & East Surrey Water service reservoirs across east Surrey, parts of west Sussex, west Kent and south London.

The contract recognises G4S's position as the UK's leading critical national infrastructure (CNI) protection specialist, with contracts including: the provision of a major security system to protect toxic gas and chemical supplies at Anglian Water's clean water treatment sites across the UK; a specialist Gurkha services business which supports a number of utilities companies; aviation security services to 19 of the UK's airports; and the provision of facilities management for secure sites such as GCHQ and the Met Office.

The contract will ensure that Sutton & East Surrey Water is in better compliance with measures laid down in the Security and Emergency Direction 1998 (SEMD), the government directive which aims to protect water supply and sewerage services from disruption by civil emergencies or security events.

Keith Whitelock, group managing director of G4S Technology, commented: "We are delighted to have been awarded this contract which builds on our proven expertise of supporting the water industry in the protection of its infrastructure. We believe Sutton & East Surrey Water is one of the leaders in the sector in planning for and implementing this type of solution and are very pleased that we can help to maintain security across its most critical sites."

Simon Thomson, Security Manager for Sutton & East Surrey Water, stated: "G4S demonstrated that it had the resources and expertise to provide a joined up security service to protect our reservoirs. We are confident that our partnership will enhance our already strong security arrangements."