Name
7B3 - Integrated Risk Management Strategies For Compound Events In Hydrology Under Climate Change Scenarios
Date
Wednesday, October 28, 2026
Time
11:35 AM - 12:35 PM
Description

Climate change is increasing the frequency, intensity, and concurrence of extreme hydrologic and coastal hazards, creating compound flood risks that exceed the assumptions of traditional single-event design. This paper presents an integrated risk management framework for compound events — simultaneous, sequential, or cascading combinations of two or more hazards that together produce impacts greater than any individual driver would cause alone. Key compound scenarios for Canadian dam safety and coastal infrastructure include extreme rainfall coinciding with elevated reservoir levels or antecedent saturation; storm surge and high tide restricting inland drainage during watershed flooding; wind-generated waves loading structures during elevated still-water levels; and management or operational decisions interacting with severe natural conditions. The paper argues that Standards-Based Approach (SBA) design criteria remain essential but must be complemented by Risk-Informed Decision Making (RIDM) and Trigger Action Response Plans (TARPs) to address uncertainty, human factors, sequential loading, and climate non-stationarity. A practical four-step framework is developed that combines these three approaches, supported by schematic figures illustrating each compound mechanism type. International and Atlantic Canadian case studies demonstrate how interacting hazards amplify risk beyond single-event predictions. The paper concludes with a recommendation that practitioners performing freeboard assessment for coastal-adjacent structures in Atlantic Canada adopt a four-step compound-event framing as an extension of existing CDA guidance. 

Location Name
Cima+ Room (501/502)