• Integrated Flood Hazard Management Plan Part 2: Breaking New Ground for Flood Analysis

  • Project Components:
    Asset Management, Planning, Conference Presentation, Water Resources
Integrated Flood Hazard Management Plan Part 2: Breaking New Ground for Flood Analysis
2017 BCWWA Conference

KWL's David Roche and David Roulston of the District of Squamish made a series of presentations on ground-breaking work in flood hazard management planning.

Abstract:

Located where five mountain rivers meet the sea at Howe Sound, the community of Squamish, BC is exposed to an imposing array of overlapping flood risks.  Managing these risks means making complex decisions: mitigating some hazards may exacerbate others, and every choice can have hidden costs.  In 2014, the District of Squamish began a ground-breaking three-year study that has now produced BC’s first comprehensive Integrated Flood Hazard Management Plan (IFHMP).  The IFHMP provides long-term recommendations for community development and capital planning that consider the impacts, benefits and costs for individuals, the community as a whole, and the environment.

This second of three presentations focuses on the technical analyses undertaken to support the IFHMP.  Statistical and modelling assessments required new approaches and tools to incorporate climate change and anticipated development at the Year 2100 horizon.  Results include hazard maps (water level, inundation extent, flood depth, velocity and physical hazard) for four different river systems as well as consequence maps (economic, social, and environmental) for the heavily-developed Squamish River floodplain.  Parallel studies assessed debris flow risk on the Cheekeye Fan.  Recommendations adopted by Council include planning for a new 7 km long sea dike and a higher dike design standard for the Squamish River, which could ultimately create capital spending obligations that approach $100 million.  Over 100 specific mitigation measures are grouped into seven categories including land use management, building requirements, diking and structural flood protection, watershed and river management, emergency planning, public education, and flood insurance. 

 

Resources: 
Presentation (application/pdf, 6.335Mb)