The first claim has been filed against Severn Trent Water, with similar claims pending against Thames Water, United Utilities, Anglian Water, Yorkshire Water, and Northumbrian Water. These companies are accused of downplaying pollution incidents, specifically sewage spills, in violation of environmental regulations. This case marks the first collective action focusing on environmental compliance and reporting obligations.

Professor Carolyn Roberts, an environmental consultant represented by Leigh Day, is bringing these claims on behalf of more than 20 million overcharged household customers due to alleged monopoly abuses by the companies. Severn Trent Water alone faces a claim from 8 million customers valued at £330 million, while the combined claims could result in over £800 million in compensation if successful. The allegations center on these firms deceiving the Environment Agency and Ofwat about their pollution incidents, negatively impacting rivers, lakes, coastlines, and other water bodies.

Water companies are legally required to report such incidents, influencing the prices they can charge for services. Professor Roberts contends that if these companies had accurately reported these incidents, penalties would have lowered customer costs.

Anyone who paid these water companies for service from April 2020 may be eligible for compensation if the case succeeds, extending to April 2017 for Severn Trent Water customers. Compensation is pursued through opt-out collective proceedings, simplifying the process for affected individuals. Customers are automatically included unless they choose otherwise, with no obligation to take action unless the claims succeed.

Claims against the other water companies will follow in the coming months if the initial case prevails. Any compensation would come from the water companies and their shareholders, not customers' bills, in the event of success.