26505 (2023). Lan Pham to the Minister for the Environment

26505 (2023). Lan Pham to the Minister for the Environment: What, if any, are the main sources of freshwater pollution in Aotearoa?

Hon Penny Simmonds: Both urban and agricultural areas contain major sources of contaminants. The main forms of freshwater pollution in Aotearoa are: - Nitrate-nitrogen: Livestock urine is the dominant source in pastoral areas. - Phosphorus: Phosphorus often enters waterways attached to eroded sediment, and a major source is surplus nutrients from fertilisers. - Sediment: Historically, the replacement of native forests with pasture after widespread land clearance created a highly erodible landscape. Clear felling of forestry, stock trampling and earthworks (e.g. for urban development) are major activities that exacerbate erosion risk and sedimentation. - Pathogens: the main sources of pathogens in waterways include stormwater when it washes animal dung off land, failing wastewater systems, or incomplete treatment of wastewater. The following report provides more detail: • Our Freshwater 2023