Brighton & Hove WwTW Scheme

A 300m environmental improvement scheme bringing cleaner seas to Sussex

Sussex, UK


The Southern Water Brighton and Hove wastewater treatment works treats the 95 million litres of wastewater generated each day in the catchment area of Brighton and Hove to the required European standards. After treatment, the water is returned to the environment 2.5 kilometres off-shore.


Working collaboratively with Southern Water, MWH, now part of Stantec, had overall responsibility for the detailed design for the wastewater treatment works, Marine Drive and Portobello pumping stations. MWH was also responsible for the detailed design of the civil, architectural and reinforced concrete works and for the pumping station superstructures on the sewerage system, as well as local sewer connections. MWH provided specialist services including process engineering, hydraulic design, HVAC engineering, noise modelling, fire and geotechnical engineering.


Environmental impact was a key focus in the planning approval process and odour, noise and visual impact were three main considerations. A distinctive feature of this treatment works is the overall architectural design concept. MWH needed to ensure that it took account of the environmental requirements when carrying out the detail design, working closely with the multiple designers and contractors who carried out assessments in the planning phase of the scheme. The site has been arranged with the buildings located on the south and east sides of the site to effectively screen the other treatment processes from the neighbouring residential areas. In addition there is a substantial cordon sanitaire of landscaped land surrounding the treatment area. The noise impact of the plant and vehicle movements was carefully assessed through modelling and the design was adapted to suit the noise limits.


The wastewater treatment includes a high rate primary sedimentation process, a high rate biological treatment process, screens and screenings processing and grit and grease removal and processing. Indigenous sludge, plus imported sludges from other sites is anaerobically digested on site prior to dewatering. The biogas produced by the digestion plant is used in a CHP plant to produce electricity. The plant includes facilities to capture and control all odours emanating from the WTW and SRC. The odour control includes multiple stages of scrubbing and has interconnection of units to allow for maintained performance in the event of failure or shut-down of individual units. The odour control system consists of a cover and collect stage, followed by a treatment stage. Treated air is finally emitted from a common stack to atmosphere.

The Brighton & Hove WwTW scheme was awarded Project of the Year at the 2014 Construction News Awards, Green Roof Award at the Roofing Awards 2012 and Major Civil Engineering Project of the Year (Over £50m) at the British Construction Industry Awards 2013.

Images accredited to Southern Water.

Brighton & Hove WwTW Works