The Crossness Sewage Treatment Works is one of Thames Water’s largest sewage treatment works, treating sewage from a population of over 2 million. Thames Water is currently investing £220 million to upgrade the works which will allow the site to treat 44% more sewage than its current capability. Part of this upgrade was to construct a new intake pumping station to cater for the increased capacity.
The existing intake pumping station has 12 long shaft pumps which were installed by Bedford Pumps forerunner Allen Gwynnes over 50 years ago. Bedford Pumps will now replace them with 13 new dry well immersible pumps. These will consist of six Low Level pumpsets delivering 2140 l/s each fitted with 650kW motors, 4 High Level pumpsets delivering 1225 l/s each and fitted with 270kW motors and 3 Transfer pumpsets delivering 1225 l/s each fitted with 140kW motors. In addition a boxed spare will be supplied for each application. The pumps are designed to handle 180mm solids and the motors will be oil cooled. The drive will be via 690v inverters.
The Crossness project is due for completion in 2014. Bedford Pumps is working in partnership with contractor Tamesis, an integrated joint venture between Laing O’Rourke and Imtech Process.