Tsunami Preparedness Kit & Coastal Evacuation Guide
The 2004 Indian Ocean tsunami killed over 230,000 people across 14 countries; the 2011 Tōhoku tsunami killed nearly 20,000 in Japan alone. In both events, many deaths were preventable: people who recognised the warning signs and immediately moved to high ground survived, while those who waited, watched, or returned too soon did not. Tsunami emergency kit supplies and evacuation planning are essential for anyone living within a few miles of a coastline, particularly along the Pacific Coast, Gulf Coast, and Hawaii. This guide covers how to recognise a tsunami, how to evacuate effectively, and what to have ready before one arrives.
Natural Warning Signs of a Tsunami
Tsunami warning systems have improved dramatically, but natural warning signs remain your most important real-time alert: especially for near-source tsunamis where the wave arrives within minutes of the earthquake. Know these signs and act on any one of them immediately:
- Strong or unusual earthquake: If you feel an earthquake strong enough to make it difficult to stand while near the coast, treat it as a potential tsunami trigger and move to high ground immediately: do not wait for official warnings
- Ocean recession: If the ocean suddenly pulls back dramatically, exposing the seafloor: this is the most visible sign of an incoming tsunami wave. Do NOT go down to look at the exposed seafloor; move to high ground immediately
- Unusual roaring sound: A loud roaring sound coming from the ocean, sometimes described as a freight train, may precede a wave
- Unusual wave behaviour: Waves arriving without wind, multiple waves arriving in rapid succession, or sudden dramatic changes in water level
Official Tsunami Warning Systems
- NOAA Tsunami Warning Centers: The Pacific Tsunami Warning Center (PTWC) and West Coast/Alaska Tsunami Warning Center (WC/ATWC) monitor seismic activity and issue warnings for Pacific and Alaskan coasts; warnings are issued within 3–5 minutes of triggering earthquakes
- Wireless Emergency Alerts (WEA): Tsunami warnings automatically push to cell phones in affected areas: same system as Amber Alerts
- NOAA weather radio: Continuous broadcast of all coastal hazard warnings, including tsunamis; the most reliable alert for coastal residents during power outages
- Tsunami warning sirens: Installed in many coastal communities, particularly in Hawaii and Pacific Coast cities; know the difference between a test and an active warning in your area
- Limitations: For near-source tsunamis (earthquake originating close offshore), warning time may be 5 minutes or less: too short for official systems to reach you before natural signs are already visible
Tsunami Evacuation: What to Know Before One Happens
Tsunami evacuation is not something to figure out during the event. The decisions: where to go, which route to take, where to meet family: must be made in advance.
Know Your Tsunami Zone
- Most coastal states with tsunami risk have published evacuation zone maps; find yours at your state emergency management agency or NOAA’s TsunamiReady program
- Inundation zones show the maximum expected flood extent for a major tsunami: if your home is in an inundation zone, your evacuation destination must be outside and above it
- Know your zone designation (A, B, C in many systems) and which zones require evacuation for which threat levels
Evacuation Route Planning
- Move inland and uphill: The goal is elevation; 100 feet of elevation above sea level places you above most tsunami inundation zones in most scenarios
- Know multiple routes: Coastal roads are often the most direct but fill quickly and may be blocked by the earthquake that triggered the tsunami; know alternate routes through inland streets and uphill paths
- On foot if necessary: In a near-source scenario with no time to drive, on-foot evacuation may be faster; know your walking routes to high ground
- Never drive toward the coast after an earthquake in a tsunami-prone area to assess conditions; many deaths occur from people returning to check on property
- Tsunami evacuation signs: Many coastal communities have blue tsunami evacuation route signs: follow them and identify them before an emergency
Evacuation Triggers
- Natural warning signs (ground shaking, ocean recession, roaring sound): Move immediately without waiting for official confirmation
- Official Tsunami Warning issued for your coast: Move immediately; do not wait to see the wave
- Tsunami Advisory issued: Hazardous currents possible; stay away from beaches and harbours
- Tsunami Watch issued: A tsunami has been generated but may not affect your area; be ready to evacuate on short notice
Tsunami Go-Bag: Pre-Packed for Instant Departure
In a near-source tsunami scenario, you may have 5–15 minutes from the earthquake to departing your home. Your go-bag must be by the door, pre-packed, and require no assembly time.
Documents & Financial
- Waterproof document sleeve: insurance policies, IDs, passports, property documents
- USB drive with all document scans and irreplaceable photos
- Cash ($500+) in waterproof bag
Survival Supplies (72-Hour Minimum)
- Water: 1 gallon per person (or Sawyer Squeeze filter for sourcing after flooding)
- 3-day food supply: non-perishable, no-cook options
- Water purification tablets × 50: tsunami floodwater is heavily contaminated with saltwater, sewage, and debris
- First aid kit (comprehensive)
- All prescription medications (30-day supply)
- Sleeping bags or emergency blankets × 1 per person
Communications & Navigation
- Midland ER310 emergency radio (NOAA, hand-crank, solar): cell service may be unavailable
- Phone + charger + power bank (waterproof-rated)
- Paper maps of your county and evacuation routes: GPS may be unavailable
- Whistle × 1 per person: for signalling if trapped or injured
Protection & Tools
- Waterproof dry bag (35L+): to waterproof the entire go-bag contents
- Waterproof boots or closed-toe shoes: post-tsunami debris and water
- Work gloves × 2 pairs
- N95 masks × 10: post-tsunami air quality from debris and mould
- Headlamp × 1 per person + spare batteries
Coastal Home Preparation
Know Your Structure’s Vulnerability
- Elevation matters most: A home at 50+ feet above sea level and 1+ miles inland is far less vulnerable than one at sea level beachfront; know your home’s elevation (check topographic maps or your county GIS)
- Wood-frame construction: Most American coastal homes are wood-frame and will not withstand direct tsunami wave impact; they are not safe shelters: evacuation is always the answer
- Vertical evacuation structures: In some tsunami-prone communities, designated buildings (reinforced concrete, elevated) are designated as vertical evacuation refuges when horizontal evacuation is not possible: know if your community has them
Before Tsunami Season (Pacific Coast: Year-Round)
- Register for local emergency alerts through your county emergency management office
- Conduct a family tsunami drill: physically walk your evacuation route to identify obstacles
- Anchor heavy furniture and water heaters (earthquake mitigation also reduces post-earthquake debris hazards)
- Store valuables and documents digitally and in the cloud: physical property in inundation zones may be destroyed
- Review your homeowner’s/renter’s insurance coverage for tsunami/flood damage (standard policies do not cover flooding)
After a Tsunami
- Do not return until authorities declare it safe: Multiple waves often follow the first: the second and third waves may be larger than the first; people who return early are frequently killed by subsequent waves
- Stay at your evacuation destination until all-clear is issued: A tsunami event can produce hazardous waves for 8–12+ hours after the triggering earthquake
- Assume all floodwater is contaminated: Saltwater, sewage, fuel, agricultural chemicals; avoid contact; do not consume any water that touched floodwater
- Document damage before beginning cleanup: for insurance claims and disaster assistance
- Be alert for structural damage: Earthquake and tsunami combined may have compromised structural integrity of buildings; look for cracks, foundation damage, and gas leaks before re-entering
- Apply for FEMA disaster assistance: After federally declared disasters, FEMA provides financial assistance for temporary housing, repairs, and property loss at disasterassistance.gov
Recommended Products
Midland ER310 Emergency Crank Weather Radio
For coastal residents in tsunami-prone zones, a NOAA emergency radio that operates without grid power or cell service is a non-negotiable preparedness item. The Midland ER310 receives NOAA weather alerts including tsunami warnings, operates on hand-crank or solar charging (no batteries required), and includes a USB port for charging phones. During a tsunami event, cell towers and power grid infrastructure in the affected area will likely be compromised for hours or days: the ER310 maintains communication when every other channel fails. Store one in your go-bag and one in your home; the SAME alert programming ensures it wakes you for warnings specific to your county even in standby mode.
- NOAA SAME alert programming: county-specific tsunami warnings
- Hand-crank + solar: no grid power or batteries required
- USB phone charging port; waterproof-rated housing
Sawyer Products SP131 Squeeze Water Filtration System
Post-tsunami water supplies in coastal areas are contaminated and unavailable for days to weeks. The Sawyer Squeeze filters 100,000 gallons lifetime, removes 99.99999% of bacteria and protozoa, and is compact enough to store in any go-bag. In a tsunami scenario where you’ve evacuated to higher ground and are waiting for infrastructure to be restored, the ability to source clean water from streams, ponds, or rainfall dramatically extends your self-sufficiency. At $30, it’s among the most cost-effective long-term survival investments available. Pair with water purification tablets (iodine or chlorine) for chemical contamination that filters alone don’t address.
- 0.1-micron filtration; removes 99.99999% bacteria and protozoa
- 100,000-gallon rated lifetime; compact for go-bag storage
- Extends water self-sufficiency when infrastructure fails post-tsunami
LSAG Waterproof Dry Bag Backpack (30L)
A waterproof dry bag backpack is the ideal tsunami go-bag format: it keeps all your supplies dry if you’re caught in wave edge conditions, allows hands-free evacuation on foot, and serves as flotation support if you’re caught in moving water. The 30L capacity fits a full 72-hour kit. Roll-top closure with double-fold and buckle provides genuine waterproof protection under submersion. For coastal residents, this is preferable to a standard nylon backpack as your go-bag because tsunami inundation zones have standing and moving water: your bag and its contents need to survive immersion. Store it pre-packed near your front door throughout the year if you live in a tsunami inundation zone.
- Waterproof roll-top closure: survives submersion
- 30L capacity; backpack carry for hands-free foot evacuation
- Essential for go-bags in tsunami inundation zones
Tsunami Preparedness FAQ
How far inland do I need to be to be safe from a tsunami?
Distance from the coast is less important than elevation. The critical factor is vertical elevation above sea level: not horizontal distance. A location 100 feet above sea level and a quarter mile inland may be safer than a location 2 miles inland but only 10 feet above sea level in a river valley. Most major tsunami inundation maps for the US Pacific Coast show inundation extending 1–3 miles inland for maximum credible tsunami scenarios, but in low-lying coastal valleys and river mouths, water can travel much further. The safest approach is to check your specific location against official inundation maps (available from your state emergency management office) and to know the elevation of your home, your evacuation destination, and your route. On the US Pacific Coast, most state emergency management agencies publish free downloadable tsunami inundation maps.
What should I do if I’m on a beach and feel an earthquake?
If you feel an earthquake while on or near a beach: particularly a long-duration earthquake or one that makes it difficult to stand: move immediately to high ground without waiting for any official warning. This is the most important rule for near-source tsunami survival. Do not wait to see if the water recedes. Do not wait for sirens. Do not stop to gather belongings. Simply move uphill as fast as possible. For a near-source event (earthquake originating close offshore), you may have as little as 5–15 minutes before wave arrival. If you are in a building, go to the highest floors: vertical evacuation within a reinforced concrete building is preferable to staying at street level if you cannot reach high ground before a wave arrives.