Nutrient recovery from wastewater for urban agriculture? Assessing risks and governance implications of a new agri-food technology

While modern agriculture is a major cause of environmental pollution, including large-scale nitrogen- and phosphorus-induced environmental change, the consequences of climate change put agricultural production systems increasingly under pressure. Post-exceptionalist agri-food policymaking promotes technology innovation as a pillar for managing negative environmental impacts of agricultural production. New agri-food technologies, such as vertical farming and nutrient recovery technologies, pave the way for visions of circular and high-tech agricultural systems of the future. The paper deals with the governance implications of such technologies that fuel new cross-sectoral policy-interlinkages, e.g. between water, food and energy (Schwindenhammer & Gonglach 2021), and the probability of new risks and unintended effects (Schwindenhammer 2020). Building on risk governance research and studies of technology innovation and cross-sectoral agri-food governance, the paper assesses an emerging technological approach to urban agricultural production in Germany. The SUSKULT approach envisions the connection of the wastewater treatment system and the agricultural production system. It projects the transformation of a conventional sewage treatment plant into a “NEWtrient®-Center”, which draws the essential resources for urban hydroponic plant cultivation from municipal wastewater. Building on qualitative and participatory research methods, the study provides deeper insights into policy debates and risk governance implications of nutrient recovery from wastewater for urban agriculture. The paper shows that while the SUSKULT approach has the potential to contribute to more sustainable urban food systems, it simultaneously fuels new governance issues, e.g. the regulation of limit values for contaminants of emerging concern, and related policy debates on cross-sectoral risk governance that challenge established food and water governance frameworks.