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ping application (based on Google Maps) that allows individuals to ind speciic addresses and
see tsunami evacuation zones relative to more identiiable landmarks (Appendix D). Because it
is critical for individuals to understand the extent of tsunami evacuation zones in their commu-
nities, the committee commends the NTHMP for acknowledging a deiciency in map availabil-
ity and citing the need for guidelines for the approval and distribution of maps in its 2009-2013
draft strategic plan. Efforts to centralize the availability of evacuation maps, or at the very least
to develop a NTHMP portal that guides individuals to disparate state archives, will enable indi-
viduals to more easily ind evacuation materials and prepare for future events.
In addition to inconsistencies in map access, tsunami evacuation maps are inconsistent with
regard to formats, colors, and noted landmarks (e.g., bridges, assembly areas, hospitals, hotels to
help tourists, instructions on whether to evacuate by foot or car). The formats of currently avail-
able tsunami evacuation maps vary and include community-based maps that emphasize land-
marks (see Appendix D; Alaska), single tsunami evacuation zones (see Appendix D; Washington,
California, Oregon, Puerto Rico), and multiple tsunami evacuation zones to differentiate between
local and distant tsunamis (see Appendix D; Cannon Beach, Oregon; Figure 2.1). Recent updates
to the Cannon Beach map that show two tsunami evacuation zones (one for a distant tsunami
and another for a near-ield event; see Figure 2.2) may be the most scientiically justiied, but no
studies have been conducted to determine whether at-risk individuals in this community under-
stand these differences and would know whether to evacuate certain areas given live drills
of the two scenarios. In general, there is no rigorous evaluation of how people respond to or
interpret maps. Evacuation maps in Oregon, Washington, California, and Puerto Rico use yellow
to denote tsunami evacuation zones, while in Hawaii the static maps found online denote the
hazard zones as gray and the maps in phone topics in red. Variations also exist among tsunami
evacuation maps with regard to accompanying text on the map products that explains how to
use the map and to prepare for future tsunamis (Table 2.5).
To date, state mapping efforts have largely relied on their own state advisory groups to
guide evacuation map development. Because tsunami scenarios that form the basis for evacu-
ation maps will vary among states (e.g., distant versus local events or worst-case versus most
likely), map content will always need to be tailored to the special facilities and populations
in tsunami-prone areas. However, the preparation and presentation of this information (e.g.,
symbols, colors) in a consistent way across the United States helps create a consistent voice
in public education and is encouraged (see Chapter 3 for additional details). For example, a
resident of the Oregon coast who works in a neighboring coastal town in Washington or is
vacationing in Hawaii should be able to recognize and understand tsunami evacuation maps
with little interpretation. State agencies have not evaluated the effectiveness of various map
formats (either based on surveys and interviews or by testing their utility during evacuation
drills) in promoting individuals to take protective action, and there are no NTHMP guidelines
for evacuation map preparation.
Although consistency in evacuation map preparation does not currently exist, the commit-
tee commends the NTHMP for noting the need for guidelines on evacuation map preparation
(including assistance to non-English speaking communities and criteria for deining evacuation
routes and sites) in its 2009-2013 strategic plan (National Tsunami Hazard Mitigation Program,
