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Key Milestones At Treatment Works

18 February 2016

The redevelopment of Southern Water’s wastewater treatment works at Woolston in Hampshire has reached a number of key milestones.

The 4Delivery team, a joint venture between Veolia, Costain and MWH, made a breakthrough recently in successfully diverting wastewater through a newly constructed temporary plant.

The existing wastewater treatment site, built in 1966, was in need of modernisation. The site serves over 65,000 Southampton residents, therefore simply shutting it down wasn’t an option.

The new temporary treatment works is situated on land adjacent to the aging works and took a year to complete. During its construction, the team notched up 300,000 man-hours without any significant accident or incident, marking another major achievement for the team.

“We were working on leased land that was a former shipyard and we had to deal with contaminated material, poor ground conditions and working around existing services, all while maintaining a fully operational treatment works. We’re delighted to have completed the temporary wastewater treatment works on time, within budget and without any major accidents or incidents. Everyone on the team can be extremely proud,” said Chris Roberts, the Project Director.

Now the temporary site is operational, work has started to demolish the existing works and construct a new permanent site. This phase of the project will take up to three years to complete.

Once completed, the £63m project will ensure the treated wastewater meets new, higher environmental standards. In line with the latest European Union requirements (under the Urban Wastewater Treatment Directive and the Habitats Directive), the Environment Agency has specified tighter standards on the treatment of wastewater before it can be recycled into the environment.

The site is also being completely redesigned to fit in with the redevelopment of the surrounding area. The new buildings have been designed to blend into the urban area, taking into account the new developments already under construction. Fencing, walls and trees will minimise views into the site.

Once operational, customers will notice a reduction in smells and noise as the treatment units will be housed undercover and a new odour reduction plant will be in place.


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