Residents in the city claim to have been personally affected by sewage spills along the coast over the last year.

Some 58 per cent of residents in the constituency of Brighton Pavilion reported being personally affected by or witnessing sewage in the water over the last year, according to political activism group 38 Degrees.

The figure was the highest reported anywhere in the UK.

Almost half (43 per cent) of residents in the constituency also said they are struggling to pay their water bills amid rising costs.

Across seven of the most marginal constituencies across Sussex, an average of 56.3 per cent said their vote at the next election would be affected by the government’s handling of the release of sewage into rivers and seas.

​READ MORE: Council demands answers from Southern Water after damning pollution investigation

The survey, which spoke to more than 6,000 people across Britain, comes after UK’s environment watchdog claimed the government may have broken the law over how it regulates sewage releases.

Siobhan Harley, campaigns director at 38 Degrees, said: “Most of us have never thought about where our waste goes after we flush - most of us would rather not think about it.

“But when as many as 58 per cent of people in parts of Brighton are actually seeing sewage or being affected by it polluting our waters, we’re forced to confront a pretty disgusting question: where exactly is my poo?

“This isn’t an accident: it’s happening because our sewage system is outdated and not fit for purpose.

“But companies like Southern Water have picked shareholder dividends and CEO bonuses over the critical updates we need. 

“Now they’re expecting people in the region to cough up and cover the cost of clearing up after them.

“That’s why thousands of us are sharing a clear message: it may be our poo, but it’s the water companies’ mess. It’s time for them to clean it up.”

READ MORE: Water firm spilt sewage into county's waterways illegally on dry days

Southern Water said there had not been a “storm release” in Brighton since 2015 and that bills had been falling in real terms for ten years.

The firm also said no dividend had been paid to shareholders since 2017.

A spokesman for Southern Water said: "We agree with our customers that storm overflows are an undesirable feature of a legacy system, and their use is no longer acceptable.

"We are working hard to reduce their use and we are investing £3 billion – or £1,500 per household – to upgrade our network, as part of our wider Turnaround Plan - designed to deliver significant improvements in our environmental performance and customer service.

"Customer bills have remained below inflation for many years – currently water and wastewater dual service customers’ average annual household bill is £439 per year, or £1.20 per day.

"Bills are a vital source of funding used to tackle the challenges of redesigning a legacy system and building new assets to cope with increasing demands from urbanisation, and weather-related climate impacts."

Environment Secretary Therese Coffey rejected criticism of the government’s handling of sewage dumps and said her party had “taken more action than any other government on this issue”.

She said: “We have been repeatedly clear that water companies’ reliance on overflows is unacceptable.

“They must significantly reduce how much sewage they discharge as a priority.

“We are holding water companies to account, and that is also true of our regulators.”