There are certain issues, such as ageing water infrastructure and population growth, that are found in all megacities. These issues are likely to make water supply deficits in London worse over time. Addressing this threat could be done using wastewater reclamation and non-potable reuse (NPR), which has the potential to close the supply-demand gap without an impact on environmental water bodies. An important factor in this is understanding the challenges the diverse stakeholders face with regards to the governance of NPR schemes, and how these challenges can be addressed in the context of a megacity such as London.
A case study was carried out by STREAM researcher Daniel Goodwin to explore these challenges. The study was centred on a sewer mining scheme in London, where reclaimed non-potable water was used for irrigation and toilet flushing around the London 2012 Olympic Park. Qualitative analysis was done on interview and document data.
This case study shows that NPR is viable and can be used to help prevent water supply deficits in megacities such as London. Collaboration and learning opportunities were seen as necessary to improve the governance of such schemes. It also indicated that engagement activities – both formal and informal – that centred on risk management can help develop common understandings, build inter-stakeholder relationships, and help maintain trust. All these factors influence the fact that NPR can contribute to the resilience of megacities, due to the increased diversity of the infrastructure. However, its feasibility will depend on how willing stakeholders are to participate and continually negotiate new risk management practices. As more and more NPR schemes are introduced, the willingness to participate will likely rise, leading to similar schemes becoming more commonplace in megacities over time, which in turn will help reduce the water stress of these areas.
Full article: Collaboration on risk management: The governance of a non-potable water reuse scheme in London, D Goodwin, M Raffin, P Jeffrey, HM Smith, Journal of Hydrology
