Fobney WTW


Fobney WTW


Thames Water



Type of work

Electrical and Mechanical Engineering


ACIEM undertook the design, construction and commissioning of a resilience and reliability upgrade encompassing the entire low voltage installation of Fobney Water Treatment Works. The site was upgraded from a single stream supply to a fully automated changeover dual source supply. This included associated software upgrade & optic fibre network, security, fire installation and air conditioning.


ACIEM managed the project throughout all areas of work including the river intake works and pumping station, pre-ozone plant, up-flow primary filtration, low lift pumping station, post-ozonation, slow sand filtration, Granular Activated Carbon (GAC) adsorption, disinfection and high lift pumping into supply. We carried out harmonic study (before & after) of the site power supply and provided filtration equipment to compensate for any distortion due to the new switchgear.

Work undertaken included:

Decommissioning, dismantling, removal and disposal of all associated existing LV switchboards, distribution boards and switchgear; including MCCs, redundant cabling and cabling management system

Provision and installation of LV switchgear, bus bar link from the transformer integrating with the Main LV Power Distribution Switchboard in the existing HV Room; High Lift MCC & ICA; Disinfection Switchboard including UPS and modification of the existing Ozone MCC and providing dual feed system

Provision of a number of additional MCCs at critical points in the process with UPS and associated civil and mechanical engineering works

Planning and carrying out all necessary renovation work associated with the removal of the existing HV equipment and access modifications

Software upgrade for the new control and installation of fibre optic cable and ethernet communications equipment

Production of a Control Philosophy in line with Best Operating Practice for each plant area

Cleaning out of the existing lagoons, mechanical re-fit of the pump station and installation of associated buried pipework.