Thames Water has awarded contracts to five firms to work on its slow sand filters, bed rebuild and bed refurbishment programme during AMP6.

A large percentage of Thames Water’s drinking water supply is provided through Slow Sand Filtration filtration processes. The SSF beds are used as a secondary filtration process to remove turbidity and pathogens, filtering water through a bed composed of layers of sand, shingle (gravel) and GAC (Granular Activated Carbon).

Thames Water has 114 Slow Sand Filter beds spread out across five operational sites. The water company has an ongoing operational maintenance plan for SSF bed rebuilds - delivered partly in-house - which typically entails rebuilding 25 SSF beds a year.

The successful suppliers are Cappagh Public Works Limited, Watercare Utilities Limited and Western Carbons Limited.

The AMP6 contract will run for an initial duration of 3 years, with options to extend annually up to a maximum overall term of 5 years.