By 2030, it has been predicted that Southern Water customers may pay an additional £279 annually.
Leaflets from a focus group that were anonymously provided to the PA News agency revealed the plans to raise fees by 73 percent to £759 per year, accounting for inflation.
Additionally, the water company is putting forth a "least cost plan" that would save each household £10 by 2030.
According to Southern Water, the options presented in the leaflet are still under investigation.
It stated that the plans would be provided to the organization in charge ofwat in October.
According to the water company, the figures did not account for discounts of at least 45 percent given to about 125,000 households experiencing financial difficulty.
The "least cost plan" for the company would lessen the need for improvement work on sewage spills, flooding, and climate adaptation.
It promised to cut back on sewage spills by 25% by 2030 and by 75% by 2050 in the leaflets. The company has also committed to spending an additional £50 million over the next two years to lessen storm overflows.
The plans are "a disgrace," according to activist Katy Colley of Hastings Boycotts Southern Water.
She stated that Southern Water has had years to invest the required funds obtained from bill payments.
She continued, "Instead they paid millions in dividends, executive salaries, and bonuses.
"Now they want us to pay again for the work they ought to have completed already. ".
After Southern Water was fined £90 million for spills, protesters in Brighton staged a rally against sewage pollution in May.
In Kent, Sussex, Hampshire, and the Isle of Wight, Southern Water serves 2 point 6 million customers with water and 4 point 6 million with wastewater services.
For dumping billions of liters of raw sewage into the sea in 2021, it was fined £90 million.
Southern Water's Katy Taylor, chief customer officer, stated: "We know our communities want to see us invest to improve our environmental outcomes and to do it wisely. However, we also recognize the concerns about rising payments in the face of a cost-of-living crisis.
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