If I understand correctly the EA are not proposing to lower the cleanliness of rivers , but they do appear to be changing the way they report river cleanliness .
They are proposing to lower the criteria that have to be met in order to declare a river 'good'.
This means the 14% of rivers in the UK that are currently rated 'good' will be able to lower their standards and still remain 'good' (as 'good' will have been redefined).
Many of the 86% of rivers that are not currently graded 'good' but working towards it will now be graded 'good' with no further effort required. Efforts to improve them to make them good will no longer be needed as the bar will have been lowered. Indeed - in some cases they will be able to stop meeting some existing standards that they do already meet and still be graded 'good'.
The net result will be an actual reduction both in terms of current river quality and also a reduction in efforts required to improve them.
I can see your thinking but don't think that is necessarily the case .
Maybe some rivers will be classified as ''very good'' and that will become the new target ?