Design Engineer Appointed by Sutton and East Surrey Water

Mott MacDonald (UK) has been appointed design engineer by Sutton & East Surrey Water (SESW) for the upgrade of the Woodmansterne water treatment works in Surrey, UK. The plans are designed to enable the treatment works to deliver up to 50Ml/d of treated water into the supply network, helping enhance supply resilience to the 655,000 population served by the company.

Constructed in 1907, the Woodmansterne water treatment works is rated at 45Ml/d. It has undergone several changes during its life and now comprises partial aeration, partial pellet reactor softening, rapid gravity filtration (RGF) and disinfection. The raw water is locally abstracted from the chalk aquifer via boreholes and is then softened to remove dissolved minerals. Softening is known to benefit customers by reducing the amount of soap and detergents needed and minimising kettle and shower head scaling, amongst other things.

Mott MacDonald’s work to enhance and increase the performance of the RGF plant will be in three stages. The first stage includes investigative works which will look at refurbishment, expansion or replacement of plant as necessary to achieve the required 50 Ml/d works flow. The condition and performance of all civil, mechanical and electrical infrastructure will be assessed. The consultancy is evaluating options against cost, risk, constructability, carbon, operability, resilience and security, amongst other factors. The second stage involves development of a preferred option and the third stage, preparation of documentation for tender and construction.

David Thomas, Mott MacDonald’s project director, comments: “We will be using BIM delivery processes from the project outset. This has proven highly successful with our other clients and has led to cost savings in design and procurement, particularly through the efficient capture and transfer of data. We’ll be following these processes again with SESW, where the BIM journey has already commenced with a full terrestrial LiDAR survey of the entire site.”