INNOVATION July-August 2013

approves new dikes and changes to existing dikes, monitors dike maintenance by local authorities, and provides design flood levels for some of the major rivers (e.g., lower Fraser River). With the exception of well-funded municipalities, mostly concentrated in the Lower Mainland, local jurisdictions rarely have the capacity to undertake quantitative flood risk studies let alone develop and coordinate flood management programs with upstream or downstream communities. The federal/provincial Flood Protection Program (administered by the BC Ministry of Justice) provides funds to local jurisdictions to cost share the construction of structural mitigation works, but generally does not fund the flood risk studies required to determine where and how such works should be built. In some cases, existing policies can even hinder motivation to adopt flood prevention measures. For example, the responsibility for approving new development in floodplains falls to often pro-development local jurisdictions, whereas emergency response and post-disaster financial assistance is primarily borne by federal taxpayers and secondarily (10% of large disasters) by the provinces. Moreover, some local jurisdictions may choose not to regulate floodplain development because, once a floodplain has been designated as such, buildings not proofed sufficiently against floods (e.g., through elevation to flood construction levels) may not qualify for flood damage compensation. Even if compensated, the fixed levels of compensation may be only a small fraction of the home value, and overland flood insurance for homeowners is not available in Canada. What can BC do to prevent flood damage that, if occurring in the Fraser Valley, could represent Canada’s most expensive natural disaster? The recent experiences in Germany and Alberta suggest the following measures as a starting point: • Centralize flood risk management at the provincial level, not the municipal level. • Commit to and invest in flood hazard and risk mapping for varying flood return periods. • Ensure that programs for flood prevention include funds to quantify flood risk and optimize risk reduction measures before investing in structural flood protection. • Ensure that such flood risk assessments are standardized in their general approach and consider the potential for flood mitigation to cause downstream or upstream transfer of flood risk. • Abandon the concept of protecting against a single specific return period (the 200-year flood) with a fixed freeboard in favour of a risk-based approach, where flood consequences for a larger range of flood hazard scenarios are evaluated with consideration of climate change. • Under leadership at the provincial level, provide support and incentives to regional districts and local jurisdictions to manage flood risks more effectively (i.e., through control of floodplain development and better dikes). • More fully consider the risk implications of simply raising dikes in terms of the potential for false perceptions of safety and increased risk due to further development. • More fully invest in alternatives to dike construction, such as giving rivers space, and in these areas consider alternative

land use options such as riparian zone habitat, agricultural or recreational space. • Consider government residential flood insurance options that tie premiums to flood risk levels. • Engage in more frequent public outreach and emergency response efforts that consider mock flood scenarios. In summary, business as usual, raising or upgrading a few dikes here and there, and protecting river banks with hard engineering solutions will not alleviate the extreme losses that can be expected by a flood with long return periods as recently witnessed in central Europe or Alberta. Instead, flood prevention requires regional and inter-regional coordination, and a fundamental shift towards risk-based thinking. Implementation of the points above will cost hundreds of millions of dollars, but this is an amount that will pale in comparison with the losses of an extreme flood. The big question remains: do we need a major BC flood disaster before we move in this direction? v Dr. Matthias Jakob, P.Geo., and Kris Holm, P.Geo., are geoscientists specializing in engineering geomorphology, and are interested in a wide range of issues. They have worked extensively on landslide and flood hazard and risk assessments in North and South America and are now involved in the aftermath of the Alberta floods, working with the Town of Canmore and Alberta Transportation.

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