Households across London are set to see millions taken off their water bills after the local supplier was penalised by the Ofwat. 

The water regulator found 11 companies across England and Wales to have missed targets in areas such as water supply interruptions, pollution incidents and internal sewer flooding. 

Thames Water performed the worst and will have to return £51 million to customers. 

In a statement, Ofwat’s Chief Executive, David Black said: “When it comes to delivering for their customers, too many water companies are falling short, and we are requiring them to return around £150 million to their customers. 

“We expect companies to improve their performance every year; where they fail to do so, we will hold them to account. 

“The poorest performers, Southern Water and Thames Water, will have to return almost £80 million to their customers. 

“All water companies need to earn back the trust of customers and the public and we will continue to challenge the sector to improve.” 

READ MORE: Thames Water targeted in Ofwat sewage treatment investigation

READ MORE: Thames Water ordered to slash customer bills by £53 million

Other companies across England and Wales that exceeded their targets will be allowed to raise prices, meaning bills could go up elsewhere. 

Severn Trent Water in Coventry performed well and will be allowed to increase customer bills by as much as £63 million over the next few years. 

All water companies will be allowed to increase their prices in line with inflation. This is based on the consumer prices index and occupiers’ housing costs which hit 8.6%. 

This means that inflation-related price rises will most likely be offset by these fines.