UKWIR (UK Water Industry Research) has published a new report ‘Quantifying and reducing direct greenhouse gas emissions from wastewater treatment processes – Phase 2’.

The objective of this project was to start the practical journey for the UK and Irish water industry in the understanding of their process emission of nitrous oxide (N2O) and fugitive emissions of methane (CH4) from wastewater treatment plants. The research project has reviewed global and UK based monitoring campaigns, highlighted methodological requirements and knowledge gaps and provided a design of a national monitoring programme.

The project produced two key deliverables:

1.    A technical report: This includes methodologies for data collection and analysis, a review of monitoring campaigns, review of equipment used for N2O and CH4 monitoring, case studies, and relevance and learnings for the UK and Irish water sector. The report also highlights current knowledge gaps and areas for of focus going forward – including design of a national monitoring programme.
2.    A Good Practice Guide (GPG): This presents the key points from the technical report focussing on good practice case studies and practical examples of installation, calibration, use of equipment and derivations of emission factors (EFs). It also includes current emerging practice of mitigation for both N2O and CH4.

Full-scale monitoring of N2O and CH4 may be undertaken through existing, available technologies. To date, monitoring campaigns have followed different methodologies, not allowing easy comparisons between campaign details and outcomes. Further, there is a lack of guidance from the Intergovernmental Panel on Climate Change (IPCC) and research work on methods for data analysis, use of activity data and the basis for calculation and reporting of EFs. This makes existing facility-level monitoring and national monitoring approaches challenging.

This project was critical in initiating and helping to develop water industry guidance for emissions monitoring and, by summarising case studies from globally leading mitigation programmes around the world, to support company efforts to reduce process emissions and contribute to the global knowledge base.