Water bills set to rise for 14,000 families in controversial new trial

Affinity Water, which serves large parts of the South East, is preparing what would become the biggest experiment of its kind, potentially covering up to 14,000 properties across the Home Counties later this year.

The plans follow a smaller pilot scheme carried out between 2023 and 2025 involving 1,500 households.

Under the proposed block pricing model, customers would receive an initial allocation of water before charges increase progressively as usage rises.

Officials are also considering introducing a fourth pricing tier aimed specifically at households with exceptionally high consumption levels.

Portsmouth Water is developing two separate trials for smart meter customers during the 2026-27 financial year.

One proposal would allow households to pay in advance for a fixed amount of water at rates lower than the standard tariff, although exceeding the allowance would trigger additional charges.

A second option would provide reduced rates to households using less water than expected.

Smart meter data would be used to create personalised consumption baselines for individual properties rather than relying on postcode averages.

The company said using broad averages could unfairly disadvantage some households, with growing families expected to have the option of withdrawing from the schemes.

Meanwhile, Severn Trent, Britain's largest water supplier, launched its own rising block tariff trial in February affecting 5,000 households.

Anglian Water also began a four-year trial last month focused on non-household customers.

Labour has introduced a legally binding target to reduce water consumption by 20 per cent per person by 2038.

Baroness Brown, the Government's climate change adviser, previously suggested higher charges for watering large gardens could help reduce demand during periods of pressure on supplies.

Labour approved the billing experiments last year, drawing strong criticism from the Conservative opposition.

The Tories accused ministers of using water charges as "a means of social engineering" and described the proposals as a "tax on bath time" for traditional families.

Conservative critics also claimed the policies amounted to "class war" against households with larger properties.

Regulator Ofwat has encouraged water companies to take stronger action to curb water usage and previously suggested owners of swimming pools, hot tubs and large sprinkler systems could face premium charges during shortages.

Consumer groups have raised concerns that the pricing structures could disproportionately affect vulnerable households.

Anne Pardoe of Citizens Advice said: "Soaring water costs are already pushing people to the brink."

She added: "We've seen the real harm poorly designed reforms can cause in other sectors, like energy, as more people seek support from our services.

"It's essential that any changes to how people are charged for water, such as block pricing, are designed to protect not penalise consumers."

Ms Pardoe warned that "carefully designed safeguards must be implemented to avoid intensifying pressure on groups who have higher water needs, like families and disabled people."

Affinity Water said it was continuing to assess the water efficiency savings achieved during its initial trial, with results expected later this year.

A Portsmouth Water spokesman said: "Importantly, our approach is centred on rewarding positive behaviours rather than penalising customers."