Severn Trent water bills are set to rise by an eye-watering 46 per cent – we explain why

It is among water companies that have asked to hike consumer bills by even more than they originally requested, according to figures released by watchdog Ofwat.

The latest requests by water firms would see the average consumer bill in England and Wales rise by 40 per cent between now and 2030, costing £615 per year.

The proposed hike by Severn Trent is above that average, but below a proposed rise of more than 80 per cent asked for by Southern Water.

Earlier this year, companies asked Ofwat for bills averaging £585 by 2030, an increase of about one-third from the current average of £439.

This summer, the regulator pared back those requests to an average of £535, in its draft price review in July.

But now, after a consultation period, 10 of the 11 water companies have hit back with even higher requests than before.

Many argue that they need to spend more on upgrading their pipes, sewers and reservoirs than originally planned, and therefore need bills to go up too.

The biggest proposed rise is by Southern Water, which would see bills for its customers in Sussex, Kent and Hampshire rise by 84 per cent between now and 2030.

Thames Water, the UK's biggest provider, which is in emergency talks over a £15 billion debt pile and a worsening financial situation, has asked for a 53 per cent rise.

The next biggest hikes are by Severn Trent Water, of 46 per cent to £580, and north Wales provider Hafren Dyfrdwy, of 45 per cent to £568.

Only one company, Wessex Water, is not demanding higher bills than first requested.

Ofwat wrote in an update that the proposed increases were "mostly to meet the requirements of other regulators like the Environment Agency and Drinking Water Inspectorate".

But some of the increases are designed to meet "changes to the proposed rate of return for investors".

Ofwat is due to make a final decision on bills increases on December 19, with companies going to the negotiating table with regulators before then.

The regulator wrote: "We will consider this additional expenditure request as part of our final determinations"

The latest string of demands come amid public and political outcry over sewage spills in the privatised water industry, while companies' investors receive dividends and top executives get bonuses.

A recent performance report by Ofwat showed there has only been a two per cent reduction in pollution since 2019 despite firms committing to cutting it by 30 per cent.

Labour has suggested sweeping new laws which could see bosses face up to two years in jail if they obstruct regulators - but so far nothing has come into force.