Coal pollution turned rivers black in South Wales, with mining waste so thick that no life could survive.
But, in one of the most remarkable environmental turnarounds Britain has ever seen, a 20-year effort to clean them up has paid off – salmon have returned to all of them.
The revolution has been brought about by 20 years of work by the Environment Agency, local authorities and angling clubs, in the wake of the collapse of the South Wales mining industry at the end of the 1980s.
Waterways rescued from a blighted landscape of slag heaps, now have salmon running up them from the sea to spawn.
(Continue reading in the Independent)