A massive project to protect hundreds of homes and businesses from flooding could cost significantly more than originally expected.

The River Itchen Flood Alleviation Scheme (RIFAS) is a partnership between Southampton City Council and the Environment Agency.

The plans cover the west bank of the River Itchen in Southampton.

In 2021, the project cost was estimated at £41 million, but a recent council meeting said the cost could now be around £70 million.

According to the council, more than 100 homes and 200 businesses are currently at risk of flooding.

In recent years, proposals have been put forward to reduce risks on a 3.5-kilometer stretch of the west bank of the river.

The project would stretch from the Mount Pleasant Industrial Estate in the north to the Southampton Water Activities Centre south of Itchen Bridge.

Councillor Steve Leggett, who served as cabinet member for flooding from 2018 to 2021, said that based on Department for Environment, Food and Rural forecasts received by the council in 2016, Southampton was at risk of flooding over the next 100 years due to rising global temperatures.

“It would affect the city centre, it would affect the football stadium, it would affect ten districts of the city,” he said.

He called for the council to be given more details of the plan after the last estimate he had for the project was £70 million.

He said: “It is such an important investment in the city’s infrastructure, for the city’s growth, and it would be good to have more details.”

The Environment Agency and the Council have agreed a partnership to relaunch RIFAS in early 2019.

The timetable five years ago suggested that detailed design work could take until 2027 before a full business case could be presented.

Councillor Richard Blackman said the committee was aware that the project was “vital to the growth and prosperity of the city”.

However, there was no answer to the project progress or a possible funding gap at the committee meeting, he said.

Councillors agreed to invest £10 million in the project in 2021, with the Environment Agency to cover the rest, with the total cost expected to be around £41 million.