Utility of the Assessment Results to Establish Evacuation Infrastructure

How shall evacuation happen, what is the most effective strategy for localities to evacuate their population within a short time? These questions need to be addressed when planning for and deciding upon setting up effective evacuation infrastructures to ensure timely evacuation (Cf.

VI.4.4.2, VII.7). Here R&V-A can support such decisions. This chapter discusses the R&V-A results in terms of their utility for the process of planning for evacuation systems and infrastructures at the community level – from the generation of the respective options to their assessment, selection, and implementation.

Although, the establishment of an evacuation system includes a number of tasks and measures, such as selecting the appropriate evacuation zone, adjusting the urban street network conducive for evacuation, and setting up shelter systems (Cf. VI.4.4.2), the utility evaluation done here only refers to the R&V-R process regarding the establishment of effective evacuation shelters. Table 25 summarizes how the A results contribute to the single steps of the R&V-R process for setting up people-centred evacuation shelters.

Table 25 Utility of R&V-A for the establishment of effective evacuation infrastructure

1 Option generation Generation of options for establishing an evacuation infrastructure system

Step description This step requires the identification of options how to set up at best evacuation infrastructures, including types of infrastructures as well as the location of infrastructures.

R&V-A information required

Estimated Time of Tsunami Arrival (ETA) and Evacuation Time Map (Cf. VII.7.2, small maps)

Utility of the R&V-A results

When contrasting the ETA with the time people need to find a safe place outside the evacuation zone (Evacuation Time Map), it becomes obvious that especially vertical shelters as well as the construction of more effective evacuation routes would help tremendously to guaranteeing safe evacuation. This is not always the case. E.g.; in cases where the ETA is very long (e.g. 2 hours), vertical shelters are not necessarily required and do not have the desired impact. Hence, the assessment results’ utility is to emphasize the need of investment into evacuation infrastructures that allow for quick and safe evacuation. Therefore, the results confirm that all evacuation infrastructure options elaborated are badly needed in the case of Indonesia, and in particular the district of Cilacap.

2 Option assessment Assessing existing evacuation infrastructure performance within a spatial entity of concern

Step description Often, although not authorized, a certain level of evacuation capacity of a spatial entity already exists. Hence, the evaluation and selection of generated and assessed options relates to the assessment of the current degree of performance capacity of a spatial entity to effectively perform evacuation, which depends upon the current land use setting, as well as the structure of the built environment.

R&V-A information required

“Evacuation failure R&V map” and its disaggregated information (Cf. VII.7.2)

The R&V information reveals the spatial entities and the spatially distributed number / proportion of people that might not be able to evacuate in due time during the day and hence most probable suffer death when a tsunami event strikes (Cf. VII.7.2).

With its disaggregation it informs about the evacuation bottlenecks and fastest evacuation routes and distribution, and the capacity of existing buildings suitable to potentially function as shelters, and the identification of areas having difficulties to evacuate in due time.

Utility of the R&V-A results

A range of utilities of assessing evacuation performance (or risk of evacuation failure) exist that provide decision support for selecting the appropriate evacuation infrastructure system. The evacuation performance assessment allows for conducting the following actions:

 Determining the demand for investments into evacuation infrastructure: R&V information provides the knowledge base for judging on the current capacity / lack of capacity of the current setup of (potentially suitable) evacuation infrastructures (buildings, open space for meeting points along the evacuation zone boundary) to save as many lives as possible. Hence, the assessment unfolds the demand for investments into evacuation infrastructure, or in other words, what still has to be done in order to accomplish full evacuation capacity of a spatial entity of concern. This can be done for each of the options identified. E.g.;

the calculated amounts of people that cannot manage safe evacuation indicate the needs for vertical shelters with adequate capacity.

 Calculating costs of investments into evacuation infrastructure: Knowing the gap between the demand for evacuation infrastructure and the existing provisions of evacuation infrastructure within a community or urban area, the assessment of

also be used to decide upon a certain desired protection level for different hazard scenarios.

 Providing guidance for disaster resilient urban planning: The results can inform about the need for modifications in the current land use system in favour of quick and safe evacuation, including the acknowledgement of evacuation route systems and the integration of evacuation shelters in the urban / rural setups.

3 Option selection Selection of investment requirements to improve evacuation infrastructure based on the tsunami threat

Step description A decision need to be done how, when, and where to invest in evacuation infrastructure. The assessment of evacuation performance has laid the foundation for conducting the selection process for deciding upon the demand for investment, calculating costs and prioritizing investments. Especially selecting the different options assessed need.

The results can be used for a cost-benefit analysis to

 Spatially prioritize investments into evacuation infrastructure: Knowing for different spatial entities those spatial entities having relatively higher tsunami probability, being highly exposed and owning comparably little evacuation capacity (hot spots of mortality) then others, a prioritization can be conducted.

 Prioritization of investments into specific types of evacuation infrastructure (roads, shelters, etc.): Putting into relation the calculated option specific demand for investment and their contribution to increase the effectiveness of the evacuation system, the most effective evacuation infrastructure can be prioritized.

4 Option

implementation

Designing and locating selected evacuation infrastructure options

Step description Setting up evacuation infrastructure includes many tasks and steps, such as designating precisely the space for constructing evacuation shelters, identifying and constructing fastest evacuation routes from each point of a defined area to the nearest evacuation target point, as well as developing respective SOPs.

R&V-A information required

“Evacuation failure R&V map” and its disaggregated information (Cf. VII.7).

Utility of the R&V-A results

For the adequate design and construction of evacuation infrastructure the map is of rather little value. Serving the purpose of option implementation, the assessment results would need to be of high spatial resolution. The manner the map has been developed, it helps to broadly suggest spatial areas where evacuation infrastructure is needed but does not allow defining precisely their location within the urban morphology of a city. Other than R&V information is necessary here, such as the fabric of neighbourhood, space availability, trade-offs of specific identified spaces in terms of design, accessibility of the facility. The same accounts for implementing appropriate evacuation routes. Are new roads needed requiring resettlement as well as major alterations of the land use pattern, are fly-overs more appropriate than

measures.

5 Option performance monitoring

Monitoring the effectiveness of implemented options and measures

Step description In this step R&V-R specialists need to regularly monitor the progress and effectiveness of the implemented measures.

R&V-A information required

“Evacuation failure R&V map” and its disaggregated information (Cf. VII.7).

Utility of the R&V-A results

The utility of the Evacuation Failure R&V Map and its disaggregated information is limited. But with the same data structure and the calculation methods, newly acquired data (such as the new evacuation infrastructure implemented, modified population distribution, land use patterns) the map can be reproduced to evaluate the effectiveness of the evacuation infrastructure in a dynamically changing urban environment, also requiring adjustments of the setup of evacuation infrastructures.

Hence, the regular update of the Evacuation Failure R&V Map can be used for assessing the degree of protection level attained for specifically conducted investments in evacuation infrastructure (e.g. residual mortality rates for a specific investment).

VIII.4 Conclusion

The utility assessment has clearly shown the important value of R&V-A for establishing a people-centred early warning system but also the limitations. Four concluding sub-chapters are presented that address the utility of the R&V-A for R&V-R from different perspectives.

VIII.4.1 Overview on the Utility of R&V-A to Establish a Tsunami Warning