Southern Water has reached a key milestone on its £25 million major environmental improvement scheme at its Millbrook Wastewater Treatment Works on the Western Docks in Southampton.
The firm has rebuilt parts of the area’s wastewater treatment works,– one of the largest scheme’s in the company’s current AMP5 five-year investment period.
Flows have now been switched on at the refurbished works, meaning up to 70 million litres of wastewater per day from a population of 140,000 is now flowing through the new structures. Testing will continue until the autumn, after which the equipment will become fully operational.
Southern Water Project Manager Jon Kenrick said:
“From an engineering point of view, this has been an exciting scheme to work on It will have huge environmental benefits – the end result will be a much greener treatment works that will treat wastewater to even higher standards before releasing it into the Solent.”
Southern Water’s capital alliance partners 4Delivery team which is working on the project has constructed:
- A treatment tank which is the length of ten buses
- Sixty-eight, 16-metre long, eight-tonne beams holding the tank, which were put into position with a 350-tonne mobile crane
- Two final settlement tanks, measuring 33 metres in diameter
- Nearly a mile of new pipeline, up to 1.2 metres diameter
- More than 3km of cable ducts
- More than 100 tonnes of above-ground steelwork
In addition, 90 per cent of waste materials were either reused on site or recycled.
Construction experts praise “exceptional” scheme
A separate £20 million flood alleviation scheme currently being carried out by 4Delivery is being managed to an “exceptionally high standard”, according to industry experts.
Southern Water’s project to reduce the risk of sewer flooding in parts of Portsmouth and Southsea was assessed by the Considerate Constructors Scheme (CCS). The project comprises three new pumping stations and four kilometres of sewer, which will ease pressure on the current network during storms.
Awarding the scheme 45 points out of a possible 50, the inspector said: “This project which to be professionally managed to an exceptionally high standard.”
The inspector’s report praised the project team’s customer communication, community support and environmental care, as well as efforts to reduce its carbon footprint and keep everyone safe.
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