Adaptation of UK wastewater infrastructure to climate change

This paper provides a summary of the potential impacts of climate change on UK wastewater infrastructure and published adaptation measures and provides a set of recommendations for further research and action. Climate change is affecting wastewater infrastructure, notably in relation to sewer flooding, and further wet weather impacts are anticipated including combined sewer overflow discharges and related pollution. Dry weather impacts include increased sedimentation of solids in sewerage systems, septicity and associated odour-related issues. Overall, treatment processes are expected to improve due to increased retention times and higher temperatures, although more treatment may be required in summer to meet consents. The consequential impacts on society and the environment are not well quantified. Many of the impacts are already being addressed to some extent by water companies, and a wide variety of future interventions are being considered. Very little information was found on cost-effectiveness of adaptation options, but this could be in part due to commercial sensitivity. Recommendations include the development of indicators; the use of risk-based approaches and, where appropriate, integrated catchment and sewer system models; vulnerability assessments; monitoring programmes; and studies to identify adaptation measures and barriers to uptake, to include a systematic assessment of the benefits of sustainable urban drainage system.