Removing ammonia from the Thames estuary

Technology from water recycling specialist WPL, a WCS group company, has been selected by DP World London Gateway to deliver enhanced ammonia removal to protect sensitive waters within the Thames Estuary.

DP World London Gateway is a smart logistics hub located on the north bank of the River Thames in Thurrock, Essex, 25 miles from central London.

WPL will be providing a custom wastewater treatment plant for a new detached warehouse for 150 office workers, currently under construction in the logistics hub. The plant will be able to 7.5M3/d flow for a population equivalent of 100.

The package plant will discharge into an environmentally sensitive swale, which feeds into the Thames Estuary, and must meet stringent Environment Agency standards of 15:15:03mg/l for ammonia and suspended solids.

WPL will provide one below-ground HiPAF (high performance aerated filter) system to deliver ammonia removal, with one dosing unit and sand filter to further improve final effluent in line with the site-specific consent requirements. The design also includes a small pumping system due to the depth of the incoming drain and a pumped flow return chamber.

WPL technical manager Dominic Hamblin said: “WPL’s modular HiPAF range meets stringent European environmental discharge consent standards, without the use of chemicals. The technology is regularly specified by UK water utilities and is an effective choice for sensitive locations such as swales, which are shallow and not heavily diluted.

“The compact design of the HiPAF enables units to be installed in locations where space is at a premium, such as a busy commercial site. In addition, our sand filters are designed to remove excess suspended solids and biological oxygen demand where consent standards are above what is normally expected from a biological process.

“Once up-and-running, the plant will provide robust wastewater treatment while being low on noise, with minimal visual impact and will be easy to maintain.”

WPL’s treatment plant will be constructed by Readie Construction.

Construction is due to start before the end of 2021 and is expected to take 12 weeks.