By DAVID J. RAPPORT
In its laudable effort to “build resilience” in our community, North Salt Spring Waterworks District (NSSWD) seems to have taken a wrong turn. It is considering a partial easing of its moratorium on new hookups based on a report by hydrological engineering consultants, which projects water balances for Maxwell Lake (ML) and St. Mary Lake (SML) monthly to the end of this century. As I first argued in the Driftwood on Oct. 16, in my view, the report’s projections are not solidly grounded. Here I expand on my concerns.
The model in the consultant’s report uses historic climate data to project likely future scenarios. This assumes that our current climate regime is much like that which prevailed between 1950 and 2020. Quite the opposite: the impacts of climate change are increasingly unpredictable — what with previously unheard-of phenomena such as atmospheric rivers, heat domes and fire infernos generating their own unique weather systems — and that means we are living in a world of growing uncertainty.
The moratorium NSSWD imposed in 2014 reflected a precautionary approach to water management in the context of uncertain future water availability. Considering that the more extreme climate impacts we are witnessing worldwide have dramatically increased the level of uncertainty, one would expect an even more strongly precautionary approach today, rather than, paradoxically, a propensity to ease the moratorium.
Furthermore, the model used for the report’s projections is not based on “worst-case” scenarios, which in my opinion makes it singularly ill-suited to examine a world of increasing uncertainty. According to the worst-case scenario in the most recent assessments by the Intergovernmental Panel on Climate Change, by 2100 the average temperature of the earth’s surface might have risen by 5.7 C degrees above the pre-industrial average. Given what we are already experiencing, with an average temperature increase in the order of 1.1 to 1.3 C degrees, it is unimaginable what an increase to 5.7 C would mean for water bodies here and around the world – including whether they might vanish altogether. Far better for the purposes at hand would be to adopt a game-theoretic approach, in which the goal is to avoid the worst possible outcomes.
Importantly, the lack of solid grounding in climatology is not, in my view, the only fault in this report. Reliable estimates of future water availability for ML and SML require major input from stress ecologists, as what happens with the health of our watersheds crucially affects the quantity and quality of available water.
Finally, should the partial lifting of the moratorium make it possible for 300 additional family dwellings to be connected to ML water, that alone might result in an increase of our island’s population by nearly 10 per cent (with four-member families). At a time when watersheds are already in declining health due to local anthropogenic stress, this additional population growth would only make matters significantly worse.
In my opinion, for NSSWD to continue along this path risks increasing the uncertainty of future water availability and is likely to undermine, rather than build, our island’s resilience.
The writer served as senior scientist and science advisor to Statistics Canada and co-authored Canada’s First State of Environment Report.