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Recognizing that little of this sort of work has likely been done to date, AMEC will utilize <br />broad definitions of drought `impacts', `vulnerabilities', and `the use of assessment <br />results' during interviews to encourage the inclusion of marginally relevant efforts. <br />Results of the survey will be presented in qualitative format, and will provide an <br />empirical basis for reporting vulnerability across assets of state agencies and divisions <br />and, where possible, key facilities. These results will be analyzed and used to make <br />recommendations for planning and mitigation programs. <br />To meet FEMA requirements the vulnerability assessment must reflect changes in <br />development for jurisdictions in hazard prone areas. Since the entire state is drought <br />prone, the assessment will incorporate the change in population and housing units from <br />latest available census or Colorado Department of Local Affairs data. This will include a <br />discussion on available population projections and the projected impacts population <br />growth will have on increasing demands for municipal water supplies. Those counties <br />with significant growth will be noted as potentially vulnerable to drought from the water <br />supply perspective. <br />There are a number of examples of the application of drought indicators to characterize <br />vulnerability to drought, and in our interviews we will attempt to ascertain the utility and <br />viability to utilize an enhanced version of this approach in Colorado. Drought indicators <br />are variables used to characterize the magnitude, duration, severity, and spatial extent <br />of drought. They are typically based on hydrologic, meteorologic, or water supply and <br />demand variables, such as streamflow, soil moisture, precipitation, snowpack, <br />groundwater levels, and reservoir storage. Drought triggers, which are threshold values <br />of indicators, are used to determine the timing and level of drought responses <br />associated with drought categories. Drought categories, or levels, typically use <br />nomenclature such as "mild, moderate, severe, extreme drought," or "level 1, level 2, <br />level 3 drought ". Drought responses include both strategic long -term actions, usually <br />implemented before a drought (such as water pricing policies), and tactical short-term <br />actions, usually implemented during a drought (such as water use restrictions). Thus, <br />together, indicators and triggers often form the linchpin of a drought plan, linking <br />drought conditions with drought responses. Our goal here is to link drought indicators <br />with drought impacts so that the vulnerability of assets and sectors at risk can be <br />assessed using a system that is already in place and is already understood by <br />stakeholders. <br />Because drought has many definitions, multiple indicators are useful for representing <br />drought conditions. For instance, the SWSI drought index combines information on <br />precipitation, snowpack, streamflows, and reservoir storage. An important component of <br />the Colorado Drought Mitigation and Response Plan are the indices used to assess and <br />monitor drought conditions statewide. The existing 2002 Drought and Mitigation <br />Response Plan identifies three indices used as tools, for assessing drought in Colorado. <br />1. The Surface Water Supply Index (SWSI), 2. The Modified Palmer Drought index and <br />3. The Standardized Precipitation Index. <br />Reanalysis of drought indicators and association of drought conditions with reported <br />impacts will allow AMEC to develop a useful means of determining vulnerability. This <br />approach is analogous to the development of damage functions in earthquake risk <br />