Kauai County Hazard Mitigation

TSUNAMIS

Tsunamis are Hawai‘i’s most deadly natural disaster. They have killed more people in Hawai‘i than earthquakes, volcanic eruptions, hurricanes, and floods combined.The 1946 tsunami killed 17 people in coastal communities on Kaua‘i at Hā‘ena, Wainiha, Kalihiwai, and Nāwiliwili.

Two types of tsunamis strike our coast:

• Pacific-wide tsunamis: Created by large earthquakes, they travel to Hawai‘i from distant areas like South America or Alaska.
• Locally-generated tsunamis: Produced by geologic activity right here in the islands.

How are tsunamis monitored?
The Pacific Tsunami Warning Center (PTWC) monitors earthquakes and measures tsunami waves at sea. PTWC can provide several hours of warning time for a tsunami from a distant source. When a Tsunami Warning is issued, coastal sirens will sound. (Sirens are tested on the first work day of every month at 11:45a.m.)

HOW TO AVOID BECOMING A VICTIM!

Be aware: Notice when you are in low-lying coastal areas or near streams in coastal valleys.
When you hear the sirens:

• Turn on your radio or television for more information.
• If you are in a tsunami evacuation zone, evacuate immediately to higher ground.

When a tsunami is generated locally:

• There may not be time for the sirens to sound before waves begin coming ashore.
• Your only warning of a local tsunami may be feeling the ground shake from an earthquake or seeing the sea suddenly withdraw or begin to surge inland.

If you feel a strong earthquake, move to high ground immediately. Kaua‘i Civil Defense Agency recommends moving to 100 foot elevation for safety. If you are in a steel and/or concrete building of six or more stories move to the third floor, or above, and remain there until the “All Clear” is announced.

Do not return to coastal areas until you hear from County authorities. • Dangerous tsunami waves may continue to come ashore for several hours. • No matter where a tsunami originates, the waves will wrap around an island. All sides of our island are at risk.

Remember: if you are in a low-lying coastal area you are at risk from tsunamis.

Storm Surge

The greatest loss of life due to hurricanes is caused by coastal flooding known as storm surge. In Hawai‘i, water levels rise primarily from high waves generated by storm winds and from low atmospheric pressure near the eye of the storm. Storm surge is often amplified as streams flooded by heavy rain empty into the ocean. Large, unpredictable waves and strong erratic coastal currents make any form of ocean activity dangerous.

HOW TO AVOID BECOMING A VICTIM!

• Never go near the ocean during a tropical storm or hurricane.
• Evacuate low-lying areas when advised by local authorities.

Rainfall Flooding

Flash floods are the leading cause of direct weather-related deaths in the State of Hawai‘i. Flash flooding commonly takes place in gulches, valleys and other channels that restrict the water from spreading out. In November 2009 Hanalei Valley received 17 inches of rain in 24 hours. Kaua‘i has a damaging flood event caused by heavy rainfall nearly every year.

Why are floods so dangerous?

• Flash floods can occur within a few hours or even minutes of excessive rainfall.
• People underestimate the FORCE of water. Six inches of fast-moving water can knock you off your feet, and 2 feet of water will float your car!
• Deaths occur when people are caught in rapidly rising flood waters.

HOW TO AVOID BECOMING A VICTIM!

• Listen to your radio for the latest flash flood advisories, watches, and warnings. (*See map)
• Do not camp or park your vehicle along streams during threatening conditions.
• If your vehicle stalls, leave it immediately and seek higher ground.
• Never try to walk, swim, or drive through flood waters.
• If you come upon flood waters, STOP! You will not know the depth of the water nor will you know the condition of the road under the water.

Turn Around, Don’t Drown!

Hurricanes and Windstorms

On the island of Kaua‘i northeast trade winds prevail throughout most of the year, generally blowing at 10-20 mph, but:

• Strong gusty trades may occasionally reach 40-60 mph.
• Storms approaching from the south and southeast, called Kona storms, can produce hurricane strength winds.

Will a hurricane hit Kaua‘i?
Since 1950, 5 hurricanes or tropical storms have caused serious damage in the Hawaiian Islands. Damaging hurricanes Dot and ‘Iwa hit in1959 and 1982 with ‘Iniki (1992) being the most destructive. Winds were sustained at 130 mph and gusts topped 160 mph destroying over 1,400 houses and causing damage to over 13,000 on the island.

HOW TO AVOID BECOMING A VICTIM!

Plan ahead:

• Know the locations of the nearest designated hurricane shelters, usually public schools with reinforced buildings. When a Hurricane Warning is issued, Civil Defense will announce which shelters are open.
• Prepare a family plan noting shelter locations, and telephone numbers of friends or family on other islands, or the mainland, to use as a central contact point should you become separated or local phone service is saturated.

When a hurricane or tropical storm warning is issued:

• Follow instructions issued by Civil Defense and monitor radio or television for advisory, watch, and warning update information. (*See map)
• If time permits complete preparation activities. Board up windows and store loose objects.
• Evacuate to the nearest shelter if you are in a low-lying coastal area, along ridge lines exposed to strong winds, in an area subject to stream flooding, or in a wooden or lightly constructed building.

If ordered to evacuate, leave immediately!

Advisory – Be Aware: An advisory highlights weather conditions that are less serious than a warning, but which could lead to conditions that might threaten life and/or property.

Watch – Prepare: A watch is used when the risk of a hazardous weather has increased significantly, but its occurrence, location, and/or timing is still uncertain.

HURRICANE WATCH: An announcement that hurricane conditions (sustained winds of 74 mph or higher) are possible within the specified coastal area. Because hurricane preparedness activities become difficult once winds reach tropical storm force, the hurricane watch is issued 48 hours in advance of the anticipated onset of tropical-storm-force winds

Warning – Take Action: A warning is issued when a hazardous weather event is occurring, is imminent, or has a very high probability of occurring.

HURRICANE WARNING: An announcement that hurricane conditions (sustained winds of 74 mph or higher) are expected somewhere within the specified coastal area. Because hurricane preparedness activities become difficult once winds reach tropical storm force, the hurricane warning is issued 36 hours in advance of the anticipated onset of tropical-storm-force winds.

Remember: Hurricane season in Hawai‘i is June 1 – November 30.

Wildfires

Kaua‘i County is at risk from wildfires. In 2007, 292 acres were burned in two wildfires. In 2010, a wildfire broke out near Niumalu and six homes in Kapa‘a were evacuated.

Wildfires are on the increase. Changing weather patterns bring drier, hot weather. Development bordering forested areas heightens risk from wildfires. The majority of fires are caused by human negligence through discarded smoking products, sparks from equipment and power lines, campfires, careless debris burning and arson. Wildfires are a threat to human safety and destroy precious natural resources.

HOW TO AVOID BECOMING A VICTIM!

Preventing wildfires is the single most important way to avoid becoming a victim.

• Clear dry brush and other combustible materials from around your house.
• Never throw lighted matches, cigarettes or other burning items on the ground or from your car.
• Build campfires only in permitted areas and always have enough water to put them out.
• Don’t burn refuse or debris, it adds to air pollution, and can carry sparks for long distances.

If you are camping or hiking in rural or wild country and become caught in a wildfire:

• Find any kind of depression with as little flammable fuel (dry wood, brush, etc.) as possible.
• Remove fuel away from the spot while the fire approaches.
• Lie face down in the depression and cover yourself even if you only have sand or dirt.
• Remain down on the ground until the fire has passed.
• If your clothing should catch on fire: Stop, drop, and roll!

High Surf

In Hawai‘i more injuries are caused by high surf than by any other coastal hazard. High surf (10-20 feet) arrives along north facing shores each winter. Large waves (4-6 feet) strike south shores during summer months.

HOW TO AVOID BECOMING A VICTIM!

• No matter how strong a swimmer you think you are, remember Hawai‘i’s surf is among the most powerful on earth.
• Large surf often generates powerful rip currents that no one can swim against.
• Swim only at beaches with lifeguards. Check with them about ocean conditions prior to going into the water.
• Watch the surf for at least 15 minutes to allow time to see a large set of waves, and judge how big the surf is.

If In Doubt, Don’t Go Out!