Thames Water have commissioned a resilience project for the current Mogden STW to meet flow and quality consent for the design population equivalent (PE) of over 2.4Million. The upgrades are being carried out by Kier, the principal contractor, predominantly revolving around the improvements to resilience and capacity of secondary treatment systems and improving the resilience of the Sludge and Digester Streams. As part of the upgrades planned at Mogden Sewage Treatment Works a number of temporary and permanent piles were required in a number of different locations across site.

SPI Piling Ltd, were employed by Kier Ltd for the design, supply and install a permanent sheet piled cofferdam for the pipe pumping station as well as a temporary steel sheet piled cofferdam for the pipe trench.
Sheet piles were supplied and installed using the ABI leader rig supported by a mobile crane and the pipe trench was subsequently extracted utilising a Kowan WP150 Tosa some 6 months later.