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🔥 Wildfire: prevention and evacuation
Between October and April, heat, dryness and wind turn any spark into a fire that climbs a hillside faster than a person walks. The problem isn't only the forest: it's the wildland-urban interface, where houses sit directly against dry grass and ravines.
The overwhelming majority of Chile's wildfires start because of something a person did. A cigarette butt, a badly extinguished campfire or a spark off an angle grinder is enough. That's why prevention is the only real lever: on hot, dry, windy days, simply don't light fires.
Key Why the wildland-urban interface is so dangerous
- The interface is where the city touches the fuel. It's enough that your yard ends in dry grass, scrub or a vacant lot. And once the first house burns, it lights the next one.
- Valparaíso and Viña stack every factor at once: steep hills, ravines that act as chimneys, afternoon wind and timber houses packed close together.
- Fire runs uphill, because it preheats the vegetation above it. Never flee uphill ahead of a fire, and never shelter at the top of a ravine.
- Embers arrive before the flames. Wind throws burning embers far ahead of the front, and they ignite a leaf-filled gutter, a timber deck or the dry front lawn.
- A single access road shortens your margin: you have to leave earlier. And the uncut grass on the lot next door is your problem too.
Before Getting the house ready for the season (October–April)
- Clear 10 metres around the house: short grass, no dry scrub, limbs pruned to two metres, canopies separated. The first few metres against the wall: gravel, bare soil, or low well-watered plants.
- Remove anything that burns like a torch: pines, eucalypts, cypress and acacias against the house, dried bougainvillea, bark mulch against the wall, and synthetic awnings.
- Prepare the roof and gutters: clear the leaves, fit fine metal mesh guards, and screen the attic vents. That's where an ember gets in and the house catches from the inside.
- Look underneath, not just around. Dry leaves collect under a timber deck or the stairs, and that's where an ember settles. Close it off with mesh and keep it clean.
- Keep firewood, gas and fuel away: firewood ten metres off and never against the wall; the gas cylinder ventilated; petrol and paint outside the house.
- Keep water and a hose that reach the whole perimeter, plus jerrycans in reserve: in a big emergency the pressure drops, and an electric pump dies the moment the power goes.
- Park the car facing the exit, tank over half full, keys always in the same place. Plan two escape routes and a meeting point. Leave your kit by the door: checklist →
- Don't light fires or use spark-throwing machinery on dangerous days. Firefighters use the 30-30-30 rule as an alarm signal: above 30 °C, humidity below 30 %, wind above 30 km/h.
During If the fire is coming your way
- Report it immediately: 130 (CONAF) for the fire, 132 (Fire Department) if houses or people are at risk. Give the district, road or a visible landmark, and which way the smoke is moving.
- Leave early, as soon as authorities say so, ash or embers fall, or the wind turns towards you. Smoke closes the road long before the flames arrive.
- Wear long-sleeved cotton and closed shoes; synthetics melt under radiant heat. Head away from the fire and the wind, on main roads, never cutting through ravines.
- In the car: windows up, low beams on, ventilation on recirculate, and drive slowly. If the smoke catches you on foot, crouch and breathe close to the ground through a damp cloth.
- Don't try to defend the house once the flames are close: no home is worth a life. If you're left with no route, find the most open ground — already-burnt terrain, a sports field, the beach — and lie down in a dip until the front passes.
5 minutes The evacuation list: what to take, and in what order
- First, the people. Count everyone out loud and assign one adult to each child, older person or person with limited mobility. Nobody goes back.
- Second, pets and animals. Collar, leash and the carrier you already had ready. For large animals, open the gate onto bare paddock: penned in, they have no chance.
- Third, the kit and the medication, with prescriptions, glasses, inhaler and chargers.
- Fourth, the documents: ID, deeds and policies in the folder you already prepared. If there's no time, photograph them.
- Fifth, if seconds remain: hard drives, the box of photos, and a cotton jacket. Nothing else.
- Before you close the door: shut off the gas, close the windows, and leave the outside lights on so the house shows through the smoke. No padlock on the gate — fire crews need to get in.
- Tell someone which way you're leaving — a neighbour and your out-of-region contact — and confirm when you reach the meeting point.
Smoke When the fire is far away but the city fills with smoke
- Smoke travels far further than fire. A fire tens of kilometres away leaves a city smelling of burning for days: no flame risk, but fine particles that reach deep into the lungs.
- Higher risk: small children, older adults, pregnant women and anyone with asthma, COPD or heart disease. If you use an inhaler, keep it on you.
- Stay indoors with everything shut and gather the family in the smallest room with fewest windows. Air the house out when conditions improve, early morning or when the wind shifts.
- Home filtering: a HEPA purifier in the shelter room with the door closed, or a good-quality air filter strapped to the intake side of a box fan.
- What doesn't work: handkerchiefs, wet t-shirts or surgical masks. A well-fitted N95 or KN95 does help — but it won't seal over a beard. Suspend outdoor sport, and indoors skip the candles and the grill.
- Seek care if you get difficulty breathing, chest pain, a cough that won't settle or dizziness. With asthma or heart disease, that means going in immediately.
After Coming back
- Only return when authorised, and in daylight. There are still hotspots, logs burning under the ash and weakened trees that fall without warning. Assume every downed cable is live.
- Check the roof, attic space and corners several times on the first day: an ember can flare back up hours or days later. Touch the walls to feel for heat.
- Wear a mask, gloves and closed shoes to clean up: cold ash damages the lungs too. Dampen surfaces before sweeping and don't use a leaf blower.
- Photograph the damage before cleaning and keep the receipts: that's what your insurer and the municipality need for the damage survey and state assistance.
- Watch out for the first rains on a burnt hillside. With no vegetation to hold the water, the slope is exposed to erosion and mudflows: the following winter carries a different risk.
Frequently asked questions
What number do I call if I see a wildfire?
Call 130 (CONAF) for the fire itself, or 132 (Fire Department) if houses or people are at risk. Give the district, road or a visible landmark, and which way the smoke is moving.
When should I evacuate?
As soon as authorities say so, or earlier if you see dense smoke approaching, embers falling, or the wind turning towards you. Smoke closes the road long before the flames do.
How do I protect my house if I live near forest or grassland?
Clear at least 10 metres, with no dry scrub and no bark mulch against the wall. Clean gutters and roof, screen the attic vents, and store firewood away from the house.
How do I protect myself from the smoke?
Stay indoors with everything shut, gather the family in the smallest room, and only air the house out when conditions improve. Use a HEPA purifier if you have one and avoid outdoor exercise.
Should I wet the roof before evacuating?
It helps very little: the water evaporates within minutes and won't stop an ember igniting a gutter full of leaves. Having cleared those 10 metres protects you far more. Never stay behind with a hose waiting for the fire.
What if smoke reaches my city but the fire is far away?
You can have an orange sky with no fire risk at all. Don't evacuate, but do take care: windows shut, a HEPA purifier, no outdoor sport. A well-fitted N95 helps; surgical masks don't.
How do I evacuate with pets or livestock?
Have an ID collar, leash and carrier ready from the start of the season. Dogs and cats leave with you, never shut in. For large animals, open the gate onto bare paddock.
Do you manage a condominium or a residents' community? Chile's Law 21.442 requires an up-to-date emergency and evacuation plan. Build your emergency plan →