Arlington Water Treatment Works (WTW), a 20 million liters per day (mld) plant near Eastbourne, is operated by South East Water. The site receives its water supply from a nearby reservoir, which is replenished from a neighboring river during the winter months. The plant comprises clarifiers, rapid gravity filters (RGF), granular activated carbon (GAC) filtration, and chemical dosing, including ferric chlorite at the clarifier stage.

Over time, some of the RGFs had experienced media loss of approximately 300-500mm, resulting in turbidity spikes and impacting the run times of the GAC filters. To address these challenges and improve overall performance, an upgrade was undertaken. Colloide was initially approached to propose solutions for replacing the existing filter floors. In response, our team developed various options in-house, including a new dual lateral floor design with revamped launder arrangements.

As part of the comprehensive upgrade, the five RGFs were upgraded with new media, control valves, isolation valves, and other necessary components. Colloide played a vital role in executing these improvements, ensuring efficient and reliable filtration processes.