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Chichester Wastewater Treatment Works

Ultraviolet light is now being used to treat stormwater that leaves the works and enters Chichester Harbour.


The £2 million improvement scheme will significantly improve the quality of water released into the harbour during storms and at times of high groundwater levels.

New ultraviolet channel

Storm flows will now pass through an ultraviolet channel to be disinfected before it is released.

The plant is now able to treat up to 300 litres of stormwater per second – that’s the equivalent of about 31,000 pints every minute.

Ultraviolet disinfection has been used at treatment works to help clean wastewater for many years. However, using ultraviolet light to clean storm flows is a first for us.

Chichester Harbour

The harbour is an environmentally sensitive location and we, among others, have a responsibility to help protect it. By providing this treatment, we'll make sure flows entering the harbour from our site are of consistent high quality.


The works received a significant upgrade in 2008 when processes were installed to remove nitrogen and use ultraviolet light to disinfect the treated wastewater.

The scheme was carried out by our contractor 4Delivery, who also built a pumping station and stand-by generator on the site.

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