The state of the River Cleddau
Unfortunately, the evidence is clear that these waterways are in serious decline. Water quality in the National Park has sunk from 48.3% of water bodies achieving at least good status in 2017 to 33% in 2024.
One of the most iconic rivers in the National Park is the River Cleddau which has seen a dramatic decline in health and calls from campaigners to get a grip on the issue fast.
West Wales Rivers Trust have previously highlighted that in the Eastern Cleddau 72% of pollution incidents came from agricultural premises between 2016 and 2022. Slurry was the primary pollutant and only 2 waterbodies in the Eastern Cleddau catchment are in good overall health.
The Western Cleddau SAC suffers from some of the highest concentrations of phosphorous of all Welsh SAC rivers and our research with The Rivers Trust shows that there are no signs of things changing. The reasons for not achieving good status are overwhelmingly attributed to agriculture and rural land management as a contributing factor (72% of failing water bodies) whilst sewage pollution (22%) and urban and transport (22%) are the second highest contributing reasons for failure.
82% of water bodies along the river are deemed to be in a moderate, poor or bad ecological state, whilst only 18% achieved a good status. Storm overflows (which includes sewage) in the river are the highest of the six rivers at risk we looked at with 34,567 hours spillage across 33 occasions in 2024. Agriculture is also the main cause of dissolved phosphorus in the waterbody with an average of 71 tonnes of dissolved phosphorus ending up in the river each year. This equates to 73% of phosphorus in the river coming from agriculture whilst storm overflows and sewage treatment works account for 18%.
The average habitat quality assessment for the river is also rated as only 49.1 out of 100. A higher score represents more diversity in habitat along the river, suggesting that almost half of the river has a poor habitat for biodiversity to thrive and manage the impacts of erosion and climate change.
