Improving climate change resilience of drinking water infrastructure
2 April, 2024, Toronto, Canada - In a hybrid event hosted by The Water Resources Society of York University and the UNITAR Global Water Academy, moderated by Professor Stephanie Gora from the Lassonde School of Engineering; Michael Chaulk, a Process Engineering Manager at CBCL Limited, presented to a group of faculty, students, and practitioners on the subject of “Adapting utility design guidelines for climate change resilience in water supply and treatment.”
The presentation focused broadly on issues of wastewater treatment in the face of global climate change, and focused on the Atlantic Canadian provinces as a case study. Atlantic Canada presents particularly interesting challenges in light of wastewater treatment design, given its decentralized populations, low water table, and its location along major Atlantic Storm Tracks. Notably, Atlantic Canada is also host to over 190 wastewater treatment plants servicing 2.5 million residents.
Atlantic Canada is vulnerable to climate change and extreme climatic events, including floods, droughts, high winds, and fires. Thus, climate change adaptation plans for wastewater and water management infrastructure is imperative. “Climate change can not only have impacts on hard assets, such as infrastructure, but also the water quality of the source water. Thus, infrastructure needs to be resilient not only to climate extremes, but also recognize that water quality conditions won’t be the same in the future. Thus identifying optimal water treatment strategies becomes more challenging in a changing climate”, emphasized Mr. Chaulk.
Climate change considerations for water management require the inclusion of risk assessments, which are holistic to the diverse sources of threats to infrastructure and water quality. In particular, this presentation focused on the increasing prevalence of Harmful Algal Blooms (HABs), and expounded on the complexities involved in their management. For example, HABs affect water quality by introducing potentially toxic substances (of cyanobacterial origin) and by adding colour and odour to freshwater resources. What’s more, treatment is not always straightforward, with treatment plants needing to use different compounds to treat a diverse array of toxins originating from a wide number of cyanobacteria species (also referred to as blue-green algae). Making matters more complicated still is the fact that treatment design has to be resilient to changing conditions, as the impacts of climate change are expected to worsen in coming decades.
From an engineering and planning perspective these measures require the implementation of advanced and costly technologies, which may only be required during particular times of year. Planning perspectives also require a watershed perspective that requires monitoring of source waters, and the use of an even broader complement of meteorological and limnological data to get a complete picture of risk. Taking this kind of comprehensive approach to management, while onerous, is necessary, and this seminar was an excellent primer to the diverse perspectives that are needed to solve these challenging problems.