Severn Trent, South West Water and United Utilities have had investment plans rubber stamped but the rest have been told to rethink PR19 submissions for cutting bills while plugging leaks.

Four companies – Affinity Water, Hafren Dyfrdwy, Thames Water and Southern Water – have the most work to do in order to meet the tough challenges Ofwat has laid down.

Across the board, water companies are proposing significant improvements for customers in the period 2020-25.

This includes a 15% reduction in leakage and at least £10bn worth of extra investment to meet more stringent environmental standards, connect new homes and meet increased demand over the coming years.

Ofwat Chief Executive, Rachel Fletcher said: “We have challenged all water companies to deliver more for less for customers over the next five years.

“We’re seeing an increased focus on the things closest to people’s hearts such as keeping bills affordable, cutting leakage, protecting the environment and helping those most in need.

“Three companies have already stepped up to the mark with high-quality plans and stretching commitments to customers for the next five years.

“The rest of the sector now needs to meet this high standard so that customers across the country get better and more efficient services”.