Severn Trent Water has awarded contracts to install Nereda® technology at two more of its key wastewater treatment works, making the company the biggest supporter of the cutting edge water purification system in the UK to date.

Walsall Wood Sewage Treatment Works in West Midlands and Radcliffe-on-Trent Sewage Treatment Works in Nottinghamshire are both undergoing significant upgrades and are due to be commissioned in 2018. The contractor for Radcliffe is North Midlands Construction, while Mott MacDonald Bentley has been awarded the contract for Walsall Wood.

For both sites, Nereda was found to be the cheapest solution on CAPEX as well as on OPEX. Nereda is now seen as the first choice solution for any site where complete asset replacement is required. The upgrades to the works mean that Radcliffe and Walsall Wood will meet the stringent new standards for phosphorus and ammonia levels.

Image: Severn Trent visiting the Nereda^® Wastewater Treatment Plant of Carrigtwohill, Ireland.

Severn Trent is one of the earliest adopters of Nereda technology in the UK. Last year the water company awarded the contract for installing it at its Barston Sewage Treatment Works near Birmingham.

Nereda has been tried and tested around the world in a variety of countries throughout Europe,  as well as South America, South Africa and Australia.

Developed by Royal HaskoningDHV in the Netherlands, Nereda is the first process to successfully harness the benefits of aerobic granular sludge technology. 

Nereda naturally selects fast settling granules, allowing higher concentrations of active biomass to be accumulated. The compact plants achieve very high levels of nutrient removal, without chemical dosing. Applications can be new-build or retrofit. The compactness of the site – which typically requires a quarter of the land area that is needed for an equivalent conventional activated sludge – is an important plus factor in its competitiveness, in addition to its relatively low installation and running costs.

Manjit Chadha, from Severn Trent, commented:

“Installing Nereda will significantly improve the quality of effluent we put back into the water courses in both areas. In addition to the system’s efficiency and environmental credentials, which are extremely impressive, its relatively low capital expenditure requirement made it a very straightforward choice for us.”

Andrew Thompson, Technical Manager, Royal HaskoningDHV, said:

“Once you look at the whole life cost of a wastewater treatment works, choosing Nereda makes perfect economic sense - not only due to its low capital expenditure requirements but also because the operational costs are low in comparison to other treatment solutions.”