Thousands of tyres, up to 100 trolleys, and a fridge have been pulled out from a Welsh river in a major clean-up operation.
The work was the culmination of four years of planning by a dog walker who was concerned by huge amounts of rubbish in the River Ogmore, Bridgend.
About 150 volunteers and two diggers took part.
A professor in aquatic science said species may be wiped out from rivers if fly-tipping trends continue.
Dog walker Alun said he was inspired to organise the clean-up during trips with his cocker spaniel to Ogmore-by-Sea, where at low tide he would see geese perched on shopping trolleys and tyres on the riverbed.
“It’s amazing for the environment to remove this.It’s just fantastic just to see what is coming out of the river and how much is being removed,” he said.
“But with everyone coming together to do this is beyond belief – I can’t thank everyone enough.”
Among the volunteers was Jerry Cross, who was covered head to toe in mud thanks to his efforts.
“It’s tragic seeing what’s in this river today.I am shocked, we must start looking after our planet better than this,” he said.
Volunteers from charity Keep Wales Tidy recovered:
Carlos Garcias de Leaniz, professor of aquatic sciences at Swansea University, said rivers in Wales being left in this state could kill its fish.
“We have a fantastic array of sensitive species” but they are swimming in waterways filled with toxic rubbish,” he said.
“When you burn these tyres you’re releasing toxic volatile compounds – in rubber it can accumulate in aquatic organisms,” he said.
“This is not going to be something aquatic life has evolved to cope with.”
Having seen similar cases during his research of other main rivers in Wales, he has called on people to take extra care of the environment.
“Water is going to be so important in the future, it’s going to play such a role in combating and fighting climate change,” he said.
“It’s shown to improve air quality but if [rivers] are not clean then society is not getting the full benefits of these blue infrastructures.”
Another volunteer, Francesca Gribble, from Gloucestershire, said: “I’ve picked up cans, lollipop sticks, and takeaway cartons along the river and our friend even moved an armchair from the river.”
Firefighters from South Wales Fire and Rescue Service were on hand to hose off the mud from the rubbish from the river, alongside Keep Wales Tidy and Natural Resources Wales, who were all involved in the clear-up.
“This is not just one person throwing an odd tyre off a bridge,” said David King from Cardiff Rivers group.
“This must be organised, people collecting tyres as a business and tipping them straight into the river over a long period of time.”
According to Neil Harrison, from Fly Tipping Action Wales, some tyres had been in the river for more than 10 years.
“We believe some of the tyres flowing down the river catchment could be from rogue traders collecting tyres from garages or anyone who deals with tyres and dumping them into the river,” he said.
Rob Taylor, who looks after rural and wildlife crime in Wales, agreed, adding that there would be a “significant fine” if the culprits had been caught.
“Environmental crime is huge across the UK and Wales.That’s why we have strategies to deal with it,” he said.
“If they do do it and get caught, they actually get the punishment they deserve.”
Mr Taylor also highlighted the importance that education has to play and having offenders pay back into the environments they have damaged.
Additional reporting by Shazia Ali..
