🌊 Tsunami: when and how to evacuate the coast
Chile has over four thousand kilometres of coastline on an active subduction zone, and a locally generated tsunami can arrive in under 30 minutes. In that window the decision to climb is yours: recognise the natural warning signs and walk uphill straight away.
Key The three natural warning signs
- 1. A long or strong earthquake on the coast. If you have to hold on to stay upright, or the shaking lasts more than a minute, that is your evacuation order. A long earthquake, even one that feels gentle, is the kind that generates large tsunamis.
- 2. The sea pulls back. The water withdraws suddenly, exposing rocks and seaweed where there has always been sea. Don't go closer to look: if you see it, climb now.
- 3. A roar from the sea. A deep, sustained noise like a train, that doesn't match the normal surf. At night it may be the only sign you get.
- Any one of the three is enough. You don't need all three, and you don't need official confirmation. If you were wrong, you took a walk uphill and came back. Evacuating just in case is never an overreaction.
- A distant tsunami does give you time. When the earthquake happens in Japan, Alaska or the western Pacific, the wave takes hours to cross the ocean and there are no natural signs to feel. The warning comes from SHOA and SENAPRED, and it must be obeyed even if the sea looks calm.
Before Know your ground
- Find out if your home, workplace or school is in the inundation zone. Tsunami flood maps are published at shoa.cl and at your town hall. Check it for wherever you spend the summer, too.
- Learn to read the signs. They are blue with a white wave: the arrow marks the evacuation route and the circle with a climbing figure marks the safe zone where the route ends.
- Walk the evacuation route yourself, by day and by night. Time it at the pace of the slowest person in the household, not your own. Keep a second route in mind in case a collapsed wall blocks the first.
- Agree on a meeting point on high ground and on the rule that nobody goes back down for anyone: everyone climbs on their own and meets up there. Add an out-of-region contact.
- Keep closed shoes and a flashlight under the bed. After an earthquake the ground is covered in broken glass and debris. Leaving barefoot or in flip-flops ends in cut feet halfway up the hill.
- Keep your kit by the door, light and in a backpack so you can carry it on foot: water, warm layers, flashlight, power bank, medication and copies of your documents. Kit checklist →
- If there are older adults or people with reduced mobility, decide now who helps whom and by which route: a wheelchair can't climb stairs, so the accessible way may be different and longer. Practise it.
- With children, make it a repeated game, not a talk. They should know by heart which way is up, even if they're out with someone else.
During The evacuation
- Evacuate on foot, always. A car gets stuck among debris and dead traffic lights, blocks everyone behind you and leaves you trapped inside. On foot you get there.
- Climb above 30 metres over sea level, or move at least 1 km inland if there are no hills. Follow the signposted route all the way to the safe zone; don't stop short just because you can no longer see the sea.
- Leave with what you're wearing and your kit backpack. Don't go back for documents or for the car. Nothing you own is worth the minutes you have.
- With children: one adult per child, holding hands. Carry the youngest or use a baby carrier. Give one simple instruction: "we walk fast until the blue sign".
- With older adults, leave earlier and don't rush them. Support them by the arm, keep a steady pace instead of pulling, and bring their medication and cane. If someone can't climb alone, ask neighbours for help right away.
- If you're on the beach, don't gather belongings or look for your car: leave the sand in a straight line toward the nearest high ground. Keep away from river mouths — they channel the water inland.
- If you're staying in a coastal hotel, take the stairs, never the lift. If the building is solid and multi-storey and you can't reach the hill in time, the upper floors are the fallback: always upward, never down to the car park.
- If you're in a boat, don't try to return to the dock: near shore the wave breaks and destroys everything moored. Follow Navy instructions on VHF channel 16 or call 137, and head for deep water offshore.
- Warn those who don't know. Tourists and whoever is filming on their phone often don't grasp what's happening. One clear shout — "tsunami, we have to go up!" — beats any explanation.
After Stay up there
- Stay on high ground for hours. A tsunami is a series of waves minutes apart, and the first is rarely the largest. Many deaths happen to people who went back down between one wave and the next.
- Only go back when authorities say so — SENAPRED or your local emergency office — never because of a voice note or because the sea looks calm.
- Expect strong aftershocks. A large aftershock can generate a second tsunami: if you feel another long earthquake while you're up there, stay put.
- Stay out of the floodwater. It carries debris, sheet metal, fuel and sewage, and hides rebar and holes.
- Use SMS and a battery radio. Voice calls jam the network first; a short text gets through when a call won't. Save your battery.
- When you return, go in during daylight and carefully. Check for a gas smell before switching anything on, and don't restore power until the panel has been inspected.
Frequently asked questions
When should I evacuate without waiting for an alarm?
If you're on the coast and an earthquake makes it hard to stay on your feet, or lasts more than a minute, head for high ground immediately. That earthquake IS the natural alarm: don't wait for sirens, phone alerts or official confirmation.
How high or how far do I need to go?
The general reference in Chile is to get above 30 metres of elevation over sea level, or at least 1 kilometre inland where there are no hills nearby. Follow your town's signposted routes all the way to the safe zone.
How long after the earthquake does a tsunami arrive?
For a locally generated tsunami the first wave can arrive in 10 to 30 minutes, sometimes less. That's why evacuation must be immediate and on foot. A distant tsunami takes hours to cross the Pacific and is announced by SHOA and SENAPRED.
Can I evacuate by car?
No. Tsunami evacuation in Chile is on foot. After a large earthquake the streets are full of debris and the traffic lights are dead: your car stops at the first block and blocks everyone behind you, including fire crews and ambulances. Only use a vehicle if authorities say so, or if you're moving someone who cannot walk.
Does the phone alert always arrive before the tsunami?
Don't count on it. The alert is a backup, but it can arrive when you should already be climbing, and after a large earthquake the mobile network saturates. The natural signs always come, and they come first: if the earthquake was long or strong on the coast, evacuate without waiting for anything.
What if I'm a tourist and don't know the area?
As soon as you arrive somewhere on the coast, look for where the high ground is and find the blue evacuation-route and safe-zone signs. Ask at your hotel or campsite reception where the assembly point is. If a long earthquake hits, walk away from the sea, following the people heading uphill.
When can I go back down to the coast?
Only when SENAPRED or your local authority announces it officially. A tsunami is several waves over hours, and the first is not always the largest. A calm-looking sea does not mean it's over.
What does it mean when the sea pulls back?
It's a classic sign of an imminent tsunami: the sea withdraws and leaves the seabed exposed before the wave arrives. If you see it, head for high ground immediately and don't go closer to look.