The UK's water regulator on Tuesday said it has reached the next stage of enforcement cases related to a 2021 probe into non-permitted sewage discharges by water firms.
Water companies have been accused of releasing wastewater directly into rivers, watercourses and the sea during heavy rain or storms to stop pipes becoming overloaded.
The Ofwat said it has notified Northumbrian Water, Thames Water and Yorkshire Water of its provisional findings, and the companies would now have the opportunity to respond to them.
Responding to Ofwat's statement, Thames Water said it was considering the initial findings in detail and might make representations to the regulator in due course.
The regulator said it expects to publish its proposed decision for public consultation in the first quarter of 2024.
