Oceans Risk and Criteria Analysis

摘要

Given scarce resources and a continuing empha-sis on a business approach, the Canadian Coast Guard (CCG) is striving to better allocate resources among waterways, programs, and users in order to achieve the best possible level of marine safety. In this regard, the CCG has used, and is continuing to use, risk analysis and risk management tools on a project and program basis. However, to better match resources to risk (both geographically and by program) the CCG still would like an estimate of overall marine risk by program and waterway. Technically, such an estimate of risk would be given by the expected annual dollar losses by geographic area for all those hazards and associated impacts addressed by CCG programs (the annual dollar value of marine fatalities and injuries, environmental damages, clean-up effort, vessel damages and losses, cargo losses, fishery impacts, and so forth, given that no CCG services existed). Knowing the expected dollar losses by geographic area and hazard type, the CCG could then attempt to allocate available resources to each geographic area and program in a way that would optimize the reduction of these losses (i.e., maximize risk-reduction results). Although the above risk-based approach is theoretically the method of choice, many practical problems exist. To derive a geographic distribution of expected dollar losses requires a multitude of activity, probability, and value estimates for vessels, cargoes, human life, birds, mammals, and so forth. Furthermore, the past and current risk-reduction effectiveness of every existing program is needed if residual or observed risk is to be blown up into total annual risk. If applying values to life, birds, mammals, ecosystems, and so forth is too problematic, counting expected physical losses is the next desirable level of analysis. Even here, however, the analysis is time-consuming and not without controversy (e.g., each program's historical risk-reduction effectiveness still must be estimated in order to convert observed physical losses into total estimated losses). The CCG and Consulting and Audit Canada (CAC) have conducted a number of traditional risk-based analyses on a project and program basis in the past [e.g., the Confederation Bridge Risk Analysis, the Port of Hong Kong Risk Study, and various Vessel Traffic Services (VTS) Risk Studies across Canada]. However, these types of studies are relatively expensive and take considerable time to complete. The next level of analysis involves creating an index from those factors or criteria that the marine community now uses, both explicitly and implicitly, to rank risk and to allocate resources across waterways and by program [the explicit form of this approach, called Multi-Criteria Decision Analysis (MCDA), is commonly used to order complex requests for proposals, alternative policies, options, and strategies]. CAC created a display and risk index computer system with about 150 columns of risk-related data covering 100+ waterways/ports. The data were subdivided into four categories: 1. Frequency (e.g., number of cargo vessel movements, number of ferry movements); 2. Impact (e.g., metric tons of petroleum transported, number of passenger trips); 3. Modifiers (e.g., visibility, windspeed); and 4. History (e.g., vessel collisions, loss of life).