Thames Water has said the average bill for its customers could rise by nearly £100 a year in the next seven years.
The nation’s biggest water company is proposing a 1%-a-year above-inflation increase between 2015 and 2020, which will leave the average customer with a bill of around £450 a year.
The firm said the cash would help fund major infrastructure upgrades, including a new £4.1 billion super sewer to cope with London’s rising population.
A Thames Water spokesperson said: “We are proposing 1%-a-year above-inflation bill rises between 2015 and 2020 to help fund essential upgrades to our ageing pipes, sewers and other facilities so we can continue providing high-quality, affordable services to our customers while keeping pace with population growth, climate change, new laws and regulations and rising energy costs.
“We propose that by 2019-20 our average household bill will be £370 a year before inflation, up from £354 today. This excludes the cost of the Thames Tideway Tunnel, which is to set result in a maximum bill impact of £70-80 a year by the early 2020s.”
The company added its customers’ bills are the second-lowest in the country “at less than £1 a day per household”.
The water watchdog said firms need to “listen to their customers” and show they have done all they can to set plans that is “acceptable and affordable” to consumers.
Steve Hobbs, Policy Manager at Consumer Council for Water added: “People are struggling with bills at the moment and any company looking at an above inflation rise needs to consider this and demonstrate that it has explained to customers the reasons for the proposed increase and what they stand to benefit. This needs to be acceptable to customers and we will be looking for evidence of this in the Price Review.
“Even though Thames has the Tideway to deliver there will be pressure on the company to keep the cost of this project to a minimum. Previous estimates have shown the impact on bills of the Tideway would be between £70 and £80 and past research has shown this is more than customers are willing to pay.”