HIGH quality rivers and aquifers - like the vast chalk block which makes up the South Downs - benefit people and wildlife alike.

The cleaner the water, the less treatment it needs to be potable; the better the fish stocks it supports; the safer are the coastal waters to bathe in and to act as important nurseries for a range of commercially valuable marine and freshwater fish.

In the 1960s we had 'dead' rivers in Sussex and across the UK. River systems were biologically dysfunctional, largely a result of contamination with industrial and domestic waste, agricultural chemicals washed in from farmland, habitat loss and alteration - including canalisation and flood defence structures.

Otters - the iconic top of the wetland food chain - declined and disappeared from Sussex over a couple of decades ago.

Domestic legislation has done much towards cleaning up the dire state of our rivers and improving water quality. But, as we entered the new millennium, along came the EU Water Framework Directive (WFD) creating a significant obligation: to get our water environment into a fit state for people and wildlife no later than 2027.

So far it’s generated tighter legislation to prevent water pollution or abstracting more than the systems can tolerate; it’s removed a range of chemicals and nutrients found in common household products which damage the water environment; it’s banned the sale of invasive non-native aquatic plants. Above all, the process has forced our public authorities to evaluate and monitor the actual state of our rivers and water bodies according to agreed standards.

To be effective, nature conservation needs a ‘landscape scale’ approach and that is what is promoted by the WFD; a large scale holistic ecosystem approach to restoring our water environment to ‘good ecological status’. That should make it easier for otters to recolonise Sussex.

  • Dr Tony Whitbread is chief executive of Sussex Wildlife Trust