Campaigners are urging their MP and environmental agencies to do more to combat agricultural pollution.
Foresters against Fouls, a campaign group in the Forest of Dean, met with local MP Mark Harper, the Environment Agency and Welsh Water in Cinderford, to discuss water quality in the River Wye.
“It was a really good meeting,” Mr Harper, Conservative, said.
Campaigner Andrew Darke added he hopes Mr Harper “starts making some changes”.
Mr Darke said: “We are concerned residents who are aware of our problems in our local environment.
“We wanted to make sure Mr Harper is engaging with these issues.
“We need someone with the clout of an MP to really put their mind to it and start getting some answers and making some changes.”
Foresters against Fouls say that sewage and agricultural run off from farms gets discharged into the river.
Consequently, algae grows in the river, limiting oxygen and making it harder for wildlife to survive.
The Wye, which flows through Wales, Herefordshire and Gloucestershire, has been affected by excessive algal growth for the past decade.
Campaigner Eiann O’Harie added: “We wanted Mr Harper to get involved in what we see as serious issues with the river.
“We want transparency and we had a discussion about the challenges we are facing.
“It’s not so much about the sewage outflows – they are only about 30% of the problem.
“It’s mostly agricultural run-off, mostly from the big chicken factories we have in the Forest of Dean.”
Mr Harper told the BBC: “As the River Wye demonstrates, it is important to improve agricultural run-off.
“This will lead to better outcomes for people who bathe and fish in the river, but also for wildlife.”
A spokesperson for Welsh Water said they “welcomed” the opportunity to speak to the campaigners.
They added: “While our treatment works contribute around 23% to the phosphorus in the river, we are committed to reducing this even further and between now and 2025 will be investing £64 million to achieve this.”
“We also shared with the group our plans to expand our near real time operation which we will be introducing in early 2024, focussing on areas of the river where we know people are swimming and accessing the water.”
The Department for Environment Food and Rural Affairs (Defra) has been approached for comment.
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