SECTION 4: RISK ASSESSMENT
facilities, historic structures, and valued natural resources (e.g., an identified wetland or endangered species habitat). Together, this information conveys the vulnerability of that area to that hazard. Certain assumptions are inherent in any risk assessment. For the Wake County Multi-Jurisdictional HMP, three primary assumptions were discussed by the HMPC from the beginning of the risk assessment process: (1) that the best readily available data would be used, (2) that the hazard data selected for use is reasonably accurate for mitigation planning purposes, and (3) that the risk assessment will be regional in nature with local, municipal-level data provided where appropriate and practical. Key methodologies and assumptions for specific hazards analysis are described in their respective profiles. Priority Risk Index The conclusions drawn from the hazard profiling and vulnerability assessment process can be used to prioritize all potential hazards to the Wake County planning area. The Priority Risk Index (PRI) was applied for this purpose because it provides a standardized numerical value so that hazards can be compared against one another (the higher the PRI value, the greater the hazard risk). PRI values are obtained by assigning varying degrees of risk to five categories for each hazard (probability, impact, spatial extent, warning time, and duration). Each degree of risk was assigned a value (1 to 4) and a weighting factor as summarized in Table 4.5. The results of the risk assessment and PRI scoring are provided in Section 4.6 Conclusions on Hazard Risk.
Wake County Multi-Jurisdictional Hazard Mitigation Plan 2019
53
Made with FlippingBook - professional solution for displaying marketing and sales documents online