Baseline geographic information on wildfire-watershed risk in Canada: needs, gaps, and opportunities

Abstract

As the pressures on water supply from shifting forest disturbance regimes continue to escalate, researchers are being asked to answer increasingly complex questions. However, many questions in wildfire-watershed risk (WWR) research remained unaddressed due to a paucity of relevant datasets. There are, indeed, many fundamental processes we do not understand that require additional data collection to develop risk management frameworks.As such, WWR researchers and managers face a paradox in their need to address critical questions important for the sustainability of socio-hydrological systems while dealing with incomplete information. In many cases, this leads to valuable research ideas being discarded on the account of limited data availability. However, imperfect, incomplete, or limited data should not deter researchers and managers from performing analyses to assess risk. In fact, such analyses improve the research benefit-to-cost ratio of existing data, help unravel gaps in data sources, enable generation of new hypotheses, and highlight where data availability and openness can be improved. If we do not use what we have, how can we know what we need? This issue is of particular interest in Canada, where baseline WWR information for the entire country is generally missing, despite growing concerns about water security in the face of a shifting wildfire regimes. In this commentary, we (a)identify several relevant open geospatial datasets, (b) illustrate how these datasets can be leveraged to produce simple yet relevant risk information, (c) identify some high priority data gaps that require immediate attention, and (d) discuss future avenues towards the creation of baseline Pan-Canadian WWR information. RésuméAlors que les changements dans les régimes de perturbations forestières exercent une pression croissante sur l'approvisionnement en eau, les chercheurs doivent répondre à des questions de plus en plus complexes. Pourtant, de nombreuses questions relatives à la recherche sur les risques incendies dans les bassins-versants (RIBV) restent ignorées en raison du manque de données adéquates. Il reste, en effet, de nombreux processus

A call for strategic water-quality monitoring to advance assessment and prediction of wildfire impacts on water supplies

“…Water-quality monitoring in watersheds that are vulnerable to wildfire, including parameters listed in (Table 1), would provide critical baseline data for assessing how wildfires impact watersheds. Improved postwildfire water-modeling capacity, driven by data integration that reduces prediction uncertainty, would further advance the ability of the wildfire-science community to provide actionable intelligence for water supply planning and protection (e.g., Neris et al, 2021;Nyman et al, 2021;Steblein et al, 2021;Robinne et al, 2022). Remotely sensed characterization of post-wildfire water quality could provide a globally available sentinel of water-supply hazards.…”

“…In addition, because wildfires can reduce the threshold precipitation intensity at which overland flow occurs, post-wildfire stream discharge and sediment concentrations can be orders of magnitude greater than they would have been for similar storms pre-wildfire (Wondzell and King, 2003;Murphy et al, 2015), which poses challenges to current monitoring capabilities. As a result of these challenges, there are numerous gaps in post-wildfire water-quality data (Yu and Cheng, 2008;Rust et al, 2018;Basso et al, 2022;Hampton et al, 2022;Paul et al, 2022;Robinne et al, 2022;Raoelison et al, 2023), as shown in Figure 1.…”