Project Outline

The project was devised primarily to meet the new Effluent Quality Standards but to also make significant environmental improvements to the River Lea and surrounding areas. An added benefit was to address a long term flooding issue that had prevailed on the site for many years when the River Lea level was high. As Principal Contractor, Murphy managed all aspects of the design from Hydraulic, Civil and Structural designs, through to MEICA and Temporary Works designs. Temporary works designs were completed by our in-house Temporary Works department, while the permanent works designs were completed in conjunction with our sub-contract partners: AECOM for civil design and Nomenca for MEICA.

The new pumping station required an internal diameter of 18.5m and an invert depth of 21m to provide operational freeboard to the invert of a low level sewer, which was 15m below ground level. The new pumping station included two dry wells to house the associated controls and pumps. To account for the permanent shaft design, which included a 600mm thick in-situ concrete internal lining and a 3.5m deep base plug to resist flotation forces, the temporary shaft required a 24m deep dig to formation.

The scope included

  • A new pumping station and inlet works for one of the three incoming major sewers
  • Two new storm tanks and inlet works for the new pumping station and integration into the existing storm system and inlet works
  • Total refurbishments of the two existing pumping stations and inlet works, including replacement of existing MCCs
  • Complete replacement of existing control systems with one new ‘Wonderware’ SCADA system and Power Management System
  • Two new generators to reinforce the existing site generation system
  • A new set of secondary screens built into the existing full flow to treatment stream without any loss of capacity
  • New wash-water pumping station and distribution network
  • All associated drainage, access roads and MEICA works
  • Six new transformer installations with associated civil installation and cabling works
  • Two replacement 3.3kV distribution boards
  • Installation of four new LV Motor Control Centres to replace eight existing MCCs