Swansea WwTW - New Zero Nuisance Plant

Welsh Water is the sixth largest regulated water and sewerage company in England and Wales, responsible for providing drinking water and treating wastewater for over three million people.

In December 1993 Dŵr Cymru Welsh Water appointed Hyder and VWS acting as a Joint Venture Consultancy to provide the detailed design and construction management services to assist in the attainment of their "Green Seas" initiative. The objective of the design was to create a "Zero Nuisance Plant" that would be readily acceptable to the local community and become a flagship for Dŵr Cymru Welsh Water.

In accordance with the design brief Hyder and VWS developed the design for a works measuring 190 m x 50 m x 18 m to be buried beneath the ground with extensive landscaping that disguised the existence of the treatment works from the land side. The Hyder-VWS JV collaborated with Dŵr Cymru Welsh Water during the supply and construction stages with Hyder-VWS providing technical expertise and knowledge in assessing bids and making a recommendation for Dŵr Cymru Welsh Water to purchase.

The major process stages were: Fine screening, Grit and Grease removal system, Primary Lamella Settlers followed by Activated Sludge and Secondary Lamellas, UV disinfection, Sludge Thickening, Digestion and Dewatering and finally VWS Detoxair® Odour Control System.

VWS were appointed to operate the treatment works for a period of six months working alongside Dŵr Cymru Welsh Water operational staff as the final stage of training and familiarisation of the plant before final take over.