Jump

Dwr Cymru Welsh Water

Control system for Dissolved Air Flotation plant at Felindre water treatment works

Overview

Dwr Cymru Welsh Water supplies over 900 million litres of water to over three million people every day.

To meet regulatory standards set by the Drinking Water Inspectorate the company commissioned a £21 million improvement scheme at its largest water treatment works including the installation of a Dissolved Air Flotation plant.

GPS was chosen to supply the control systems for the new plant, and upgrades to existing plants, based on a cost-effective technical solution and its ability to guarantee the continuity of the process throughout the installation and changeover.

Requirement

Supplying the Swansea area the Felindre plant treats 40 million litres of water a day from local reservoirs and rivers. The main focus of the DWI upgrade was the installation of a Counter Current Dissolved Air Floatation plant to remove a higher level of contaminates and suspended matter from raw water.

As well as the control requirements of the new plant, adding a large scale filtration process created additional requirements for control systems to manage the increased power needed to run the new plant and the increased volume of waste it generated; the full scope of work included

  • COCODAF plant: MCC
  • 11kV transformers: LV Switchboard
  • Sludge treatment plant: MCC
  • Wash water recovery plant: MCC
  • Chemical treatment plant: MCC
  • Filtration process: ICA
  • Control room: PLC and SCADA

Solution

GPS provided a networked solution based around the main MCC serving the DAF plant, and its interaction with the ancillary plant systems.

The main MCC, a 20 metre Form 4 construction, is based on a PLC system networked via a fibre optic link to the ancillary systems, and fed back to an Intouch SCADA system in the main control room, and replicated in the DAF control room.

Beyond the technical scope, the major challenge was the need to maintain the water supply and quality standards throughout the installation.

GPS won the £1.1 million contract in a competitive tender and stakeholder selection process based on case evidence to support its technical proposal and a robust changeover methodology for a stepped transfer to bring the new plant online.

Results

The changeover was achieved with no interruption to water supply or plant operations, and the extended scope effectively delivered a fully modernised and fully automated works, compliant with DWI standards.

The project was completed on time and within the budget Welsh Water had set for the project. GPS also established strong collaborative relationships with the main civil contractors including Laing O’Rourke, Black & Veach and cost consultant KBS Chandler to deliver the scheme.

Summary

  1. Industry Sector - Water
  2. Customer – Dwr Cymru Welsh Water
  3. Project scope – Control system for Dissolved Air Flotation plant at Felindre water treatment works
  4. Contract - £1.1 million; 18 month project; competitive tender and stakeholder selection process
  5. Winning criteria – Technical competency and continuity solution
  6. Product delivery - Delivered main MCC, ancillary systems and software
  7. Project delivery - Completed on time to budget

Innovation and Quality in Process Control

Discover the GPS difference