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Part III. Appendix 4: User OutreachMalcolm:1) The most damaging natural hazard on the coast is, of course, the impact of wind waves. Unlikeearthquakes, damaging wind waves can be forecast to some degree (we are publishing reliable 3day forecasts on the web at this time.) Wave runup is roughly proportional to the deep water waveheight such that large waves, especially if they coexist with high tides, can cause flood damage andincreased structural impact damage. In areas with broad shelves (most of the coasts) strong onshorewinds can cause significant storm surge, greatly increasing the flooding and structural damage.This makes local wind forecasting extremely important. Wave driven flooding, in addition todirect inundation, often causes overwash of beach sand that clogs storm drains and prevents therunoff of rainfall, adding to the flooding hazards. The loss of beach or dune sand during stormscan create a hazard in that the normal protection from wave damage has been compromised orlost. Therefore, a knowledge of the state of the beach is important to decision making on both ashort term (temporary protection of vulnerable areas) and a long term basis (planning for beachnourishment programs.)Tsunamis are rare events and damage from distantly-generated tsunamis is limited to particularcoastal geometries that amplify the runup. Because of the lack of reliable warning, especially for locallygenerated tsunamis, loss of life as well as significant property loss is often suffered.Deep water directional wave measurements coupled with effective models can provide nowcasts ofnearshore wave conditions sufficiently in advance to allow for local evacuation or protection measures.Large scale events, such as hurricanes, must depend on meteorological forecasts to providesufficient warning time.2) The community of interest can be readily divided into two groups. The first are the propertyowners, residents or users of the coastal area. Those people with a financial or personal interestin structures and infrastructure subject to damage such as roads, bridges and marinas are clearlyconcerned about mitigation of coastal hazards. Included in this group are beach users, boat ownersand businesses dependent upon beach tourism. The second group are governmental entitieswith responsibilities for insuring, maintaining, regulating or protecting the first group. These varyfrom the federal (FEMA, Corps of Engineers, Coast Guard, NOAA, etc.) to the local (police, sanitation,permitting, health, etc.) Coastal states have a variety of agencies, often paralleling their federalcounterparts.260