Your editorial (“Filthy Business”, 3 August) and coverage of the state of England’s rivers is wrong on most counts except one. Let me give you the facts.

Water quality in our rivers is now better than at any time since the start of the Industrial Revolution. All over the country, salmon and otter have returned to waters that until recently were biologically dead. That has happened because of the work of the Environment Agency, alongside that of the water companies, environmental non-governmental organisations and local communities.

Rivers in England are not currently certified as safe for swimmers because there is no current system of certification. But the bathing waters off our beaches are, and last year 388 of them (97.9%) passed the minimum standards. In 1995 over half would have failed those standards. The Environment Agency has led these improvements.

Water companies are not “free to pollute”. They have to meet tough standards set by the law and the Environment Agency, which they do meet in almost all cases. If they fail to do so we take action against them, up to and including criminal prosecution. In 2017, Thames Water rightly received the highest ever fine, over £20 million, for discharging raw sewage into the Thames.

We will always press for the toughest penalties, but sentencing is a matter for the courts who fine on a case-by-case basis. We have also been calling for tougher financial penalties to drive better environmental performance given fines are currently only a fraction of turnover. Click here to read the letter in full