The Department for Environment, Food and Rural Affairs has introduced stricter water-quality monitoring rules following severe rainfall and flooding, with water pollution remaining high despite £5 billion of investment.

The measures tighten monitoring requirements against a backdrop of persistent pollution. The investment figure underlines the scale of spending, but does not by itself establish how effective that spending has been or how water quality would otherwise have fared.

Stricter monitoring and cleaner water are distinct outcomes: the introduction of the rules is not, in itself, evidence that pollution levels have fallen.