Extra water is being released into the River Wye from the Elan Valley to help stop the river’s fish life from dying in the extreme heat – but campaigners fear it won't be enough.

Natural Resources Wales is to double the release of water into the Afon Elan from Caban Coch reservoir. The aim of this measure is to help with the effects of low water levels and high temperatures on fish stocks during the heat wave this week.

It is hoped the move will help with salmon found in the lower reaches who are at risk due to water temperatures becoming fatally high as well as reducing the risk of ponded pools ‘cooking up’ and lowering the chance of algal blooms in the river, which can lead to less oxygen in the water, which in turn causes fish to die

The water will be released from a water bank in the Elan Valley which will feed the River Wye. The water bank is a dedicated facility which stores water to be used for river management purposes.

The decision came after Natural Resources Wales and the Welsh Water Wye and Usk Foundation came to an agreement to use the water within the Elan valley reservoirs to increase the flow in the river.

Ann Weedy, operations manager for Natural Resources Wales said: “We will be monitoring the success of this intervention to help make future decision about adaptive river management.

“Because of this we have to treat each incident on a case-by-case basis and take the appropriate action where required.

“The climate emergency is real, and we can expect to see more extreme events like this in the future.

“Where we can, we will take actions to mitigate the impacts, but we all need to do more to make our ecosystems more resilient.”

However, in a statement the Wye and Usk Foundation welcomed the decision but said the 400 million litres per day being released may not be fully sufficient as their proposed 1 billion litres per day.

“The water is now on the way but this is less than we asked for," the foundation said.

"It is especially important that it gets through to the tide and we have been liaising with abstractors to try to ensure this.

“We are eternally grateful to the Herefordshire farmers who, having had the situation explained, have agreed to reduce and where possible pause entirely their abstractions for crop irrigation at this critical time.”