DATA on phosphorus levels in Welsh Special Area of Conservation (SAC) rivers shows small improvements, while interim water quality classifications for Welsh rivers hold steady.

Collaborative and concerted efforts to tackle water pollution must continue at scale to drive water quality improvements, say experts at Natural Resources Wales (NRW) as new and interim water quality data is published.

Data for phosphorus compliance shows that 50% waterbodies in Welsh SAC rivers are now meeting stringent targets, compared with 39% in 2021.

In total, 122 individual water bodies within Wales’s nine SAC rivers were assessed – eight more than were assessed for the 2021 report.

A direct comparison between those assessed in both 2021 and 2024 shows 17 moving to a pass, and five falling out of compliance.

But while there are improvements recorded, due to the changes in passes and failures on individual water bodies, the number of whole SAC river catchments with non-compliances rises from five in 2021 to seven.

The Afon Gwyrfai and Afon Eden SAC rivers in north west Wales both previously met phosphorus targets, but now each have one failing water body.

This now means that the Afon Gwyrfai SAC will be subject to development restrictions to prevent further phosphorus impacting water quality. It will not be required for the Eden catchment as the failure was driven by one high sample.

Improvements downstream in the River Wye, which is now passing the phosphorus target, means that development restrictions on neutrality can be lifted in the most downstream water body only.

However, sustainable development will still be required in order to maintain compliance in the future.

Mary Lewis, NRW’s Head of Natural Resource Management said: “The results for our Special Area of Conservation rivers are encouraging, and suggest that the scale of action undertaken in recent years is starting to make a difference.

“But we must also remember that there is a lag between our actions and measurable improvements in water quality, and it will certainly take more time before we see the kind of significant improvements we all want.

“Since our 2021 report, we have seen action at scale – by ourselves as environmental regulators, Government, industry and communities – to improve the health of our rivers.

“What is important now is that we use this evidence to continue to work towards our shared goal of better river health for people and nature. We must keep up the momentum that has been built in recent years, and we must all play our part in driving down phosphorus and pollution in our waters.”

Since NRW’s 2021 phosphorus compliance report, Nutrient Management Boards have been established in failing SAC catchments, tasked with reducing phosphate pollution.

A series of river pollution summits led by Welsh Government Ministers have brought together key representatives from different industries to deliver a plan of actions, including action to unlock housing development in phosphorus sensitive catchments.

This includes an extensive project led by NRW to review the environmental permits of larger wastewater discharges in SAC catchments. In total NRW has varied 162 permits to include or tighten a phosphorus limit – either immediately or within Dŵr Cymru Welsh Water’s Asset Management Programmes.

This work has been vital in informing water companies and local planning authorities about where there is capacity for new housing developments, without adding to the phosphorus load in catchments which are exceeding targets.

Also published today are interim classifications under the Water Framework Directive Regulations.

These show water quality remaining steady with 40% of water bodies at good or better overall status. This is the same as NRW’s most recent 2021 classification but an improvement of 3% from 2015 and 8% since 2019.

The Water Framework Directive Regulations uses a ‘one out all out’ approach for the overall status assessment, which means if one of the elements assessed fails, the whole water body fails. Without this, looking at each individual elements, 93% of water bodies reach good or better status.

The Water Framework Directive Regulations require measures to protect the ecological health of our rivers, lakes, estuaries and groundwaters using River Basin Management Plans to establish the collective actions required to achieve Good Ecological Status.

It provides a set of environmental standards for assessing the status of each water body. Regulators are required to undertake this assessment every six years. NRW has decided to publish an interim classification at year three in order to better track progress of water quality improvements.

Next financial year the Welsh Government is committing £16m to NRW’s Water Capital Programme to help tackle some of the key challenges facing our waters.

Later this year, NRW is aiming to also publish condition assessments for marine Special Areas of Conservation wholly in Wales.

Mary added: “Wales’s marine Special Areas of Conservation support a wealth of habitats and species, but like our rivers, are under increasing pressure.

“These condition assessments will be vital evidence which will help to prioritise the actions and measures needed to improve these highly protected sites.

“It is our long term ambition to align all reporting on water quality data to provide a more holistic overview of the current state of water quality in our rivers, lakes, groundwaters and the sea.”

Phosphorous pollution can lead to rapid growth of algae and poor water quality through a process known as eutrophication. Algal growth prevents light from penetrating our rivers and uses up oxygen in the water, suffocating other species in the process. Wildlife Trusts Wales warns this can lead to fish deaths and harm to other aquatic life which call Welsh rivers home. According to the Trusts, ensuring rivers are in good health is vital, not only for wildlife, but also for the quality of water needed by people across Wales and beyond. 

Reflecting on the findings of today’s report, Tim Birch, senior policy and advocacy manager at Wildlife Trusts Wales, says:  “Despite public outcry and political promises, today’s evidence shows worsening river pollution in seven of nine of our most protected natural rivers in Wales. These special rivers are officially recognised for their high importance for wildlife, yet two more are now showing significant deterioration since their last assessment in 2021, putting water quality and even more wildlife at risk. 

“At a time when our rivers should be improving, not worsening, these levels of phosphorous pollution are unacceptable. Run-off from slurry and fertilisers from intensive farming are the main causes leading to phosphorous pollution in Welsh rivers. Natural Resources Wales needs to recognise the scale of this problem so that urgent action can be taken to restore our rivers for the benefit of wildlife and people.” 

The increase in pollution of rivers in Wales is at odds with the Welsh Government’s UN Convention on Biological Diversity international commitment to reduce damaging levels of nutrients in all water bodies by at least 50% by 2030.