Wastewater treatment processes are likely to be impacted by projected changes in climatic conditions under the changing climate. The mean temperature increase in Canada is projected to be approximately twice the global mean. Thus, it is important to assess potential climate change impacts on performance of wastewater treatment plants (WWTPs) that play a key role in safeguarding the health and safety of the people and the environment. In particular, the wastewater influent temperature has been shown to impact the biological processes in the secondary treatment. Wastewater temperature is, indeed, considered as one of the main factors in microbial activities such as microbial growth and decay rates. The wastewater influent temperature is expected to be impacted by climate change due to the changes in the ambient air temperature and shifts in the snow melting season. 

This paper aims to investigate impacts of changes in the wastewater influent temperature on the performance of the secondary treatment processes. In this study, the secondary treatment process is numerically simulated using BioWin 6.0. Various scenarios of wastewater temperature including low-flow high-concentration influent in summer as well as high-flow low-concentration influent in spring are simulated, and different secondary effluent quality parameters are assessed. Sensitivity analysis techniques will be employed to identify the quality parameters and corresponding processes, which are being significantly impacted by changes in wastewater temperature. The results of this study provide insights into the potential impact of climate change on secondary treatment processes and can help with optimal operation of WWTPs under changing climate.

Impact of Wastewater Temperature and SRT Changes on Activated Sludge Processes Under Climate Change

Created in 1999, the Environmental & Water Resources Institute (EWRI) is the recognized leader within ASCE for the integration of technical expertise and public policy in the planning, design, construction, and operation of environmentally sound and sustainable infrastructure impacting air, land and water resources.

[Paper Proceedings](https://doi.org/10.1061/9780784483466)

Conference DOI: https://doi.org/10.26226/m.6329c39b68fb0e00131f77d2