The Treasury has been told not to “swallow up” millions of pounds in sewage fines amid fears the money will not be spent on ending spills.

The water regulator Ofwat handed out fines totaling £168m to three water companies last week as part of its investigation into sewage dumping and environmental damage.

Environmental groups welcomed the financial penalties, but have now have raised concerns that the Government might divert the money to other areas rather than focusing on cleaning up pollution.