Understanding the sources of phosphorus in our rivers

Too much phosphorus in our rivers can cause algal blooms which in turn affect the amount of oxygen available in the water and can harm wildlife.

As a result, its presence in our rivers is now subject to a lot of attention, with more and more people and organisations who care about our rivers wanting to know where it comes from, and what the solutions are.

That is why Natural Resources Wales and Dŵr Cymru Welsh Water (DCWW) are working together on research which will evidence what the different contributing factors are to phosphorus levels in our rivers. The reports focus on our rivers designated as Special Areas of Conservation.

The modelling approach will be used to develop plans for future wastewater investments to help ensure SAC rivers achieve water quality targets. See Natural Resources Wales / Compliance Assessment of Welsh River SACs Against Phosphorus Targets.

We also hope that the approach will help inform other sectors and facilitate a collaborative effort to reduce the amount of phosphorus in these cherished rivers.

The water quality models and their outputs which are summarised in the Catchment Modelling Reports are currently draft, pending the conclusions of an independent quality assurance which has been commissioned by NRW and can be viewed below. Final reports will be published in due course.

Updating the SAGIS River Dee Model A4 P4

2.6MB, PDF

Updating the SAGIS River Teifi Model A4 P4

2.2MB, PDF

Updating the SAGIS River Usk Model A4 P5

2.5MB, PDF

Updating the SAGIS River Wye Model A4 P4

3.4MB, PDF