|Storm Warts are the blemishes in our infrastructure system|
capacity that reduce resiliency and contribute to flood losses.
Click below for the print version of the slides (unfortunately without all the fancy animation and sounds):
Storm Warts, The Floods Awaken, A New Hope for Cost-Effective Investment in Flood Management from Robert Muir
The presentation identifies benefit cost analysis as a "New Hope" for guiding infrastructure investment, so that they deliver a high return on investment by focusing on the blemishes in storm and waterwater collection systems, aka, "Storm Warts".
The presentation reviews the statement in the media, put forth by the insurance industry and affiliated researchers, that water damages are increasing and are a key driver for increasing catastrophic losses. The presentation shares data that suggests floods have not "awakened", and are in fact becoming a smaller percentage of total catastrophic losses, as explored in a recent post.
The presentation also reviews case studies of benefit cost and economic analysis related to grey and green infrastructure, including natural infrastructure (green infrastructure, low impact development measures including wetlands and other features). This includes case studies from the recent Insurance Bureau of Canada report reviewed in another recent post. It is suggested that cost benefit studies require certain elements to be robust, reliable, and evidence-based, and that some case studies are lacking in these core requirements, representing "number stretching and concept massaging" as suggested in the Financial Post.
A comparison of return on investment, benefit cost ratios, for Markham's complete flood control program is made, including a group of low-cost, no-regrets best practices (i.e., policies and programs such as sanitary downspout disconnection, and backwater value and sump pump incentives), and city-wide grey infrastructure capital works resulting from a decade of master plans and Municipal Class EA studies.. The ROI of green infrastructure is also explored as part of a city-wide assessment, including an evaluation of potential flood mitigation benefits, as well as erosion mitigation and water quality improvements.
The need for comprehensive engineering analysis is suggested, showing that case studies that relied only on "meta-analysis", or high level estimation techniques, may not be able to provide reliable, meaningful ROI estimates sufficient to guide public infrastructure spending. Wetland, natural infrastructure benefit-cost ratio's are shown to be highly variable and potentially unreliable, as reviewed in an earlier post that incorporates some of the Storm Warts presentation (i.e., Pelly's Lake, Manitoba) and reviews other sources on natural infrastructure flood reduction potential and constraints.