Resolution No. 4814 - Laserfiche WebLink

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assumption that an hour of leisure time is worth the same to a person as an hour of work (a common economic assumption). Then, for example, 100 vehicle hours of delay per day has an estimated economic impact of $3,223 and so on. For the vast majority of roads, with "typical" traffic loads, using a economic value of $32.23 per vehicle per hour of delay provides a reasonable measure of the economic impact of road closures. Everything else being more or less equal, roads which serve as primary access/egress routes and/or serve many emergency vehicles may be given a higher priority for mitigation. For completeness, we note that roads are networked systems and a more accurate analysis of the relative priority of mitigation projects to reduce road closures should consider the network characteristics of a ~ocai road system. However, network analysis is complex, requires specialized expertise and is expensive. Network analysis may be justified for very expensive projects, such as a multi-million dollar relocation of a bridge to reduce the potential for flood washouts. However, the simple three parameter prioritization methodology suggested above is probably sufficient for evaluation of most small to medium sized mitigation projects. Rail systems are subject to the same sorts of closures as are road systems. Evaluation and pdodtization of mitigation projects for rail systems would follow a methodology closely analogous to that discussed above for road systems, with economic impact parameters appropriate for a rail system. Other transportation systems (air, ports, ferry) are also subject to disruption due to the impacts of hazards. The analysis of such systems is roughly similar to that discussed above, but mitigation projects for such systems are encountered far less frequently than are mitigation projects for roads. Air traffic to/from the Eugene Airport is subject to delay or disruption due to bad weather conditions, including rain, snow, wind, and ice. However, there are few if any mitigation actions practical to reduce such delays or disruption. Possible disruptions of air service due to loss of electric power could be minimized by ensuring that all critical airport functions have adequate emergency power supplies. 13,2 Utility Systems - Overview Evaluation of hazard mitigation projects for utility systems have some commonalities between systems that we briefly review before addressing each major utility system in turn. Utility systems such as potable water, wastewater, natural gas, telecommunications, and electric power are all networked systems. That is, they consist of nodes and links. Nodes are centers where something happens - such as a pumping plant, a treatment plant, a substation, a switching office and the like. Links are the connections (pipes or lines) between nodes. Risk assessments for utility systems are similar to risk assessments for buildings, in that the inventory of utility components is overlaid on the hazard map and the vulnerability of utility components is evaluated for the hazards impacting the utility. A Public Review Draft: August 6, 2004 13-3