Our surveyors have concerns about nutrient pollution in UK rivers. As a way of contributing to the knowledge and the clean-up of nutrient pollution, water samples are taken and tested for phosphate levels at sites that our surveyors visit. These readings are for a point in time and would vary depending on several factors. The surveyors note the local river level and state alongside the phosphate readings to provide indications of potential diffuse pollution (run-off) after rainfall. A safe level of phosphate in rivers is recognised to be between 0.00ppm-0.05ppm and the map highlights these readings along with readings that exceed these values. Please use this data freely if it helps to reduce pollution from phosphates, and please get in touch if you would like the dataset in tabular form.