Southern Water is conducting a significant surface water drainage survey across the whole of Thanet to help it target areas where significant quantities of rainwater get into the sewer system – contributing to the company’s current reliance on the storm overflow system.

The £400,000 first of its kind wastewater network survey planned for Thanet is part of Southern Water’s plans to cut pollution incidents by 75% by 2025.

Southern Water, along with local stakeholder organisations, has committed to prioritising the water quality and environment of three Sussex and Hampshire harbours in all investment decisions that may impact the areas. The utility is also carrying out an assessment to establish a natural capital baseline for future decisions.

The water company was the target of two protests at the weekend in Brighton and Peacehaven against what is described as Southern Water’s “repeated sewage dumping on the Sussex coast.”

Southern Water makes storm releases during intense periods of rainfall through long sea outfalls 2km out to sea.

“We are working towards reducing our reliance on storm releases but there are huge challenges not least from climate change which we know is going to increase the frequency of intense rainfall events,” Southern Water said.

The water company said gigantic 150 million litre storm tunnels underneath the chalk cliffs between Peacehaven and Brighton can hold a full day’s long term average rain fall which helps to reduce storm overflows in the area. However,” population growth and the effects of climate change mean they cannot always be avoided”, Southern Water explained.

The utility is pioneering a new approach – building more storm tank capacity where it will have an impact – but prioritising partnership working to prevent rain from reaching its systems through sustainable drainage, water gardens and major natural capital solutions such as enhanced and expanded wetlands.

The water company has 83 designated bathing waters in its region - 58 are rated excellent and none below sufficient. Southern Water has 367 wastewater treatment works, more than 3000 pumping stations and almost 40,000km of sewer network to serve its 4.6 million customers.

Brighton & Hove is served by Peacehaven, one of the largest and most modern wastewater treatment works in Europe, which treats more than 50 million litres of wastewater a day in dry weather. During rain, more than 100 million litres a day is typically treated.

Other initiatives currently underway include:

• A £20 million investment is being made in the Swalecliffe works to extend the short sea outfall and upgrade the pumping and control systems. This will significantly reduce the risk of spills to the beaches or inland waterway and we expect to have this scheme completed in late 2024.
• Assessing the options to better manage storm water during periods of high rainfall. In discussion with the Environment Agency, Southern has agreed the installation of permanent pumps and pipework to take the flow from the combined sewer overflow (CSO) chamber to storm tanks and release via the short sea outfall, away from the Tankerton beach and the brook. The utility is working with its delivery partners to have this up and running by the end of November 2021. By the end of October it will also have improved the resilience of Brook Road pumping station.
• Concerns were raised over a separate incident last week at pumps at the company’s Broadstairs Wastewater Pumping Station failed for a short period of time as a result of storm damage. To protect local properties from flooding, flows were diverted and a release of wastewater made via a short sea outfall at Joss Bay.

Following the fault at the Pumping Station Southern Water has continued to inspect 14 beaches in the area for any evidence of impact and clean-up if necessary until the company, the Environment Agency and Thanet District Council are satisfied no risk of environmental damage remains.

A full investigation is taking place to understand the cause of the fault.