The average water bill will rise by an average of £86 from April, the industry regulator has said.

The steep rise is part of bill increases in England and Wales over the next five years to pay for supply infrastructure upgrades and to reduce sewage discharges, Ofwat said.

The cost increases overall are higher than the regulator had proposed in July, but are lower than water companies had requested.

Water UK, the trade body for water firms, said the price increases provided “much-needed” investment for the sector.

The water industry has faced fierce criticism in recent years over pipe leaks and sewage discharges into rivers. Many firms, including the UK’s largest supplier, Thames Water, are struggling financially.

Over the next five years, the increases in water bills will average out to £31 per year, but Ofwat said firms are expected to hike tariffs by a higher amount in the first year.

However, the bill hike averages have been calculated without inflation, meaning actual bills are likely to be higher.

David Black, Ofwat chief executive, told the BBC the investment will “deliver significant reduction in sewage spills, further reductions in leakage, and drive up service for customers”.

A total of £104bn is to be spent on upgrades for the sector, which Ofwat said would deliver “cleaner rivers and seas and secure long-term drinking water supplies for customers”.

Bill hikes varies by region. Southern Water customers will be hit by the biggest increase, with bills going up 53% – to £642 on average – by 2030. Wessex and Northumbrian Water bills will rise by the smallest amount – 21%.

The announcement of bills rising for Southern Water households comes as supplies to thousands of homes are currently disrupted, with more than 58,000 properties impacted.

Thames Water, which is struggling under a huge debt pile, will be able to charge customers 35% more, with annual bills going up to £588.

Rebecca Sinker, member of the Clean Water Action Group in Hastings, said the group was “angry” about costs going up, arguing the water company there, Southern, had not been “keeping up with the infrastructure maintenance”.

“We don’t trust them to spend our money in the right way, and we can’t go anywhere else for our water. It’s a private company monopoly,” she said.

Ms Sinker said the group had been getting bacteria readings “way off the scale in terms of safety” in the sea, which was important for the area’s fishing and tourist industries.