Using SuDS to reduce nitrogen in surface water runoff

Nitrogen is essential for life, but too much nitrogen is a hazard that causes water pollution. High nitrogen levels can lead to rapid increases in algae populations in water environments, which use up the oxygen and suffocate other aquatic creatures. Alongside the risks to wildlife, excess levels of nitrogen in drinking water can also cause harm to human health. Together, these effects are very significant, and the introduction of nutrient neutrality catchment areas is a strategy to bring this water pollution under control. This guidance is intended for those developments affected by nutrient neutrality rulings. It outlines the design criteria for a good SuDS scheme that can maximise the opportunity to capture and remove nitrogen. It also describes the difficulties of capturing nitrogen, as it is present in different forms, and the many different processes to do so.