Project Description

Project: New Build & Refurbishment
Client: JN Bentley and Welsh Water
Contract Responsibilities: Main Contractor
Contract: Bespoke form of contract
Project Value: £320,000
Programme: June 2018 to August 2019

The Overview

Five Fords WwTW is a sewage works just outside Wrexham in North East Wales, blending passive and activated sludge treatment.

The total population served by the works in the Wrexham area is around 100,000, and seven tankers per day bring in sludge and domestic sewage from elsewhere in the North East Wales and Chester area.
The MMB and Welsh Water Capital Delivery Alliance set out to deliver the second phase of the Sludge Strategy Aim, the £56.2m North Wales Sludge Strategy (NWSS).

At its heart, the NWSS is a waste management strategy which aims to deliver Opex savings and enable the business to meet the Biosolids Assurance Standards from June 2018.

The other principle drivers are:

  • Production of an enhanced standard biosolid
  • Improve dewaterability of biosolid product reducing transportation
  • Increase solids destruction increasing gas yield and reducing transportation
  • Reduced reliance on aging assets for sludge treatment

The original project consisted of the construction of two new buildings, these being the Pre- THP and Post-THP buildings. This quickly developed into the refurbishment of the existing Cake Building initially to three of the elevations, and then extending to the full building, including the removal and installation of a new flat roofing system. In addition, Gallaway was also asked to complete the cladding and door installation on two belt reception units.

The Challenge

The install phase of the project was fast-tracked to deliver the Pre and Post THP buildings in time for the already ordered conveyors. Procurement lead design solutions were adapted to ensure steelwork design and lead-in durations were shortened to accommodate programme, and programme resequencing was adopted to allow the installation of the specialist plant and equipment into the building, and to then allow the building to be formed around its contents.

Refurbishment of the existing buildings was a challenge, with the contents of the building requiring cleaning prior to Gallaway
commencement, and the structural steelwork then being surveyed by Gallaway with a full defects report prior to treatment and remedial works.

The latter incorporated new steelwork member strengthening and blast cleaning, and redecoration with a suitable finish for the new proposed building usage.

The Solution

Having delivered several sludge treatment facilities across the sector previously, Gallaway were able to ensure mitigation was put into place to avoid previously encountered issues.

Lessons learnt workshops were held between Gallaway and the clients to capture pertinent points, and closely working with MMB assisted both parties through the process to deliver a high-quality product to the client.

Gallaway embraced technology within the design and procurement phases which MMB and Welsh Water were able to utilise to provide improved direct outcomes, both in terms of plant and equipment selection.

Gallaway were able to design the building around the requirements of this new plant. As part of the delivery team we strived to embrace the latest advances in technology and capturing digital design processes in order to expediate the build programme.

Five fords
Five fords waterworks
Five fords water treatment works