BYTESLIP ← Back
Knowledge Base // Tutorial 89

Outdoor Survival Basics on the Big Island (Hawaiʻi Island)

Difficulty: Easy ~20 min read Outdoors · Field Guide · Hawaiʻi Island

Hawaiʻi Island packs rainforest, lava desert, snow-capped summits and open ocean into one place, and the hazards change just as fast as the scenery. This guide covers the basics of staying safe outdoors on the Big Island, from water and weather to lava, the ocean and getting help.

Safety // Read First

Warnings

CriticalIn any emergency on Hawaiʻi Island, call 911. Never enter closed areas, never cross rising water, and when in doubt about the ocean, stay out.

Safety disclaimer: This is a general introduction, not professional training or medical advice. Conditions on the island change quickly. Always follow current guidance, closures and warnings from park rangers, lifeguards and Hawaiʻi County Civil Defense.

Checklist // Before You Start

What You Need

Setup // Step 00

Make a Plan and Tell Someone

Most rescues get easier when someone knows where you went. Before you leave:

  1. Pick an official trail or area that matches your fitness and experience, and read up on it first.
  2. Tell someone the trail name, location and when you expect to return, so they can call for help if you don’t come back.
  3. Check the weather forecast, surf conditions, air quality and any park closures on the day you go.
  4. Set a turnaround time and stick to it. Hike with a partner whenever you can.
  5. Sign up for Hawaiʻi County emergency alerts (Civil Defense and Police use the Everbridge system).
Check Park Alerts ↗
Walkthrough // Steps 01–13

Stay Safe Out There

  1. Step 1: Treat every drop of wild water

    Freshwater streams, ponds and puddles in Hawaiʻi can carry leptospirosis, a bacterial disease spread through animal urine. It enters through cuts and through your eyes, nose and mouth.

    • Never drink stream or pond water untreated. The Hawaiʻi Department of Health says to boil it for at least one minute or treat it chemically. If you also carry a filter, follow its instructions, but boiling or chemical treatment is what the Department of Health recommends.
    • Avoid swimming or wading in fresh water, especially with open cuts or sores, and don’t put your head under.
    • Be careful with rainwater catchment at campsites, cabins and rentals. Unless it is marked as drinking water, treat it as untreated. Slugs can crawl into uncovered tanks and animals can contaminate catchment areas.
    • Get medical care if you develop fever, chills or muscle aches after contact with fresh water. Symptoms can appear from 2 days to 4 weeks later.

  2. Step 2: Beat the sun, heat and dehydration

    Lava fields and the coast have little or no shade, and daytime temperatures in the national park can climb into the high 90s °F.

    • Drink before you feel thirsty. The park recommends about ½ to 1 quart of fluid every hour you hike in the heat, alternating water with an electrolyte drink, and eating salty snacks.
    • Use sunscreen with SPF 30 or higher and reapply at least every two hours and after swimming.
    • Start early and rest in shade. Heat exhaustion (pale, nauseous, cool moist skin, headache, cramps): rest in shade, drink, cool down. Heatstroke (flushed, dry skin, confusion): cool the person immediately and call 911.

  3. Step 3: Respect elevation and fast-changing weather

    You can go from sea level to nearly 14,000 feet in a single day. Mauna Kea’s summit is 13,796 ft, and winter conditions, including snow, ice, 100+ mph winds and white-outs, can happen there at any time.

    • Altitude sickness: on Mauna Kea, stop at the Visitor Information Station (9,200 ft) for at least 30 minutes to acclimate. Watch for headache, nausea, shortness of breath, dizziness and poor judgment. Severe headache, vomiting, breathing trouble, confusion or blue lips mean descend immediately and get medical help.
    • Don’t go above the Mauna Kea VIS if you are under 13, pregnant, have heart, lung or blood-pressure conditions, or went scuba diving in the last 24 hours.
    • The summit air is very dry. Mauna Kea managers suggest about 500 ml (two cups) of water per person per hour.
    • Windward vs leeward: trade winds make the windward (Hilo, east) side much wetter, while the leeward Kona side sits in a rain shadow and is generally drier. Pack for both if you’re crossing the island. Clear mornings are often followed by rain and wind later in the day.

  4. Step 4: Never cross rising water

    Gentle streams in Hawaiʻi can become rushing torrents in minutes, sometimes from rain you can’t see falling upstream. Narrow gulches are especially dangerous.

    • Warning signs: faster flow, a quick rise in water level, a distant rumbling upstream and the smell of fresh earth. Move to higher ground immediately.
    • Never cross if the water is rising or above your knees. Wait it out on the safe side, even if it means a long delay or a night out.
    • Never drive or walk through flooded roads or fords. Turn around.

  5. Step 5: Stay safe around lava and volcanic air

    • Stay on marked trails and overlooks. Earth cracks, thin crusts, hidden lava tubes and unstable cliff edges are common in Hawaiʻi Volcanoes National Park and are not always visible, even in daylight. Never enter closed areas.
    • Lava rock is uneven, jagged and very sharp. Cover your skin, wear gloves and good shoes, and watch every step.
    • Vog and sulfur dioxide (SO₂): volcanic gas can cause breathing problems miles downwind. It’s most dangerous for people with heart or respiratory conditions, infants, children and pregnant people. Check the SO₂ advisory map before you go and leave if air quality turns unhealthy.
    • Laze: where lava enters the ocean, it creates a white plume of acidic steam, hydrochloric acid gas and tiny glass shards. Even its wispy edges can irritate skin and eyes and cause breathing difficulty. Stay out of it and away from new lava deltas, which can collapse without warning.
    • If there is active lava, stay upslope and upwind, and follow park ranger and USGS guidance at all times.

  6. Step 6: Read the ocean before you go in

    • Check current beach conditions and surf warnings before you leave, and choose a lifeguarded beach when you can.
    • When in doubt, stay out. Strong shorebreak can slam you into sand or rocks, and rip currents can form even on calm, sunny days.
    • Never turn your back on the ocean. Large waves can arrive with little to no warning, including on rocky ledges and tide pools. Keep your distance from wet, wave-splashed rock.
    • Caught in a rip current? Don’t fight it. Swim parallel to the shore, then angle back to land. If you can’t, float and wave or call for help.
    • After a strong earthquake on the coast, move to higher ground immediately and stay there (tsunami risk).

  7. Step 7: Find shelter and stop hypothermia

    Yes, you can get hypothermia in Hawaiʻi. Wind, rain and altitude drain body heat fast, especially on the summits and in the wet upland forest.

    • Watch for the “umbles”: stumbling, mumbling, fumbling and grumbling, plus uncontrolled shivering.
    • Get out of the wind and rain, swap wet clothes for dry layers, have warm sugary drinks, and share body heat.
    • If you’re caught out after dark, stay put unless you know the trail well and have a light. On Mauna Kea, if you’re stuck in a winter storm, stay in your vehicle with the engine off to avoid carbon monoxide.

  8. Step 8: Navigate when there are no landmarks

    • Lava fields can look the same in every direction. Trails are often marked only by rock piles (ahu), which are hard to see in fog or darkness.
    • Download offline maps before you leave and carry a paper map and compass as backup.
    • Expect no cell signal on many trails. On Mauna Kea above the VIS, phone use is limited to emergency calls only.
    • Don’t take shortcuts. Rangers have rescued many visitors who left the trail in the Kīlauea calderas and got lost.

  9. Step 9: Fire: only where it’s legal

    • In Hawaiʻi, the state says 99% of wildfires are caused by humans. Dry grass on the leeward side can burn quickly.
    • Only have fires at official campsites that allow them. In County parks, cook with open flames only in designated fire pits or contained hibachis/grills. Some parks ban open fires entirely.
    • Fires are prohibited on Mauna Kea, including grills and portable stoves.
    • Check for County burn bans and red flag warnings before you go. Keep water ready and soak, stir and feel the coals until they’re cool before you leave.
    • If you see a wildfire, call 911.

  10. Step 10: Eat safely: rat lungworm and wild plants

    • Rat lungworm disease is found on all the islands. Never eat raw or undercooked snails, slugs, freshwater prawns, land crabs or frogs, and don’t handle snails or slugs with bare hands.
    • Inspect and rinse all fruit and vegetables under clean running water, leaf by leaf for leafy greens, even if you picked them yourself.
    • Cover your drinks outdoors so slugs and snails can’t crawl in.
    • Never experiment with unfamiliar plants. A taste of some plants can kill you. Pack in enough food instead.

  11. Step 11: Handle bugs and wildlife

    • Centipedes, scorpions and black widow spiders live here and can deliver painful bites or stings. Shake out shoes, clothes and sleeping bags before using them.
    • Mosquitoes: use EPA-registered repellent, wear long, light-coloured clothing, and take extra care in shady, damp spots around sunrise and sunset.
    • Feral pigs and hunting dogs: some trails cross Public Hunting Areas. Give animals plenty of space, never corner them, and consider wearing blaze orange.
    • Keep a safe distance from all wildlife and never feed it. Many native species are protected by law.

  12. Step 12: Signal for help and call 911

    • In any emergency on Hawaiʻi Island, call 911. In Hawaiʻi Volcanoes National Park you can also call Park Dispatch at 808-985-6170.
    • Stay calm, stay put, stay warm. You’ll be found faster if you stay in one place, which is why telling someone your plan matters.
    • Be visible: wave bright items in an open area during the day, use a flashlight or flashing light at night, and use a whistle or signal mirror.
    • Help can be delayed in remote areas, at night or in bad weather, so carry enough to wait it out.

  13. Step 13: Respect the land, closures and sacred places

    • Use only official trails. Unofficial trails are illegal in State forests and can harm native habitat.
    • Don’t cross private land without the landowner’s permission, and don’t block driveways near trailheads.
    • Native Hawaiians regard many places as sacred, including wahi pana (places of special significance) and the mountain summits. Follow signs, respect any kapu (restricted) areas and never disturb cultural sites.
    • Closures exist for your safety. Never enter a closed area.
    • Pack out all trash and leave rocks, plants and sand where you found them.
Pro Tips

Tips

Field Questions // FAQ

FAQ

Is a clear, fast-flowing stream safe to drink from?

No. Clear water can still carry leptospirosis. Boil it for at least one minute or treat it chemically before drinking.

Can it really snow in Hawaiʻi?

Yes. Mauna Kea and Mauna Loa can get snow, ice and blizzard conditions. Bring warm clothing for any trip to the summits.

I feel a headache coming on near the Mauna Kea summit. What should I do?

Headache can be an early sign of altitude sickness. Tell your group and head down. If it’s severe or comes with vomiting, breathing trouble or confusion, descend immediately and get medical help.

The stream I crossed this morning is now higher. Can I risk it?

No. Never cross rising water or water above your knees. Move to higher ground and wait for it to drop, even if that takes hours.

How do I know if the volcanic air is bad today?

Check the Hawaiʻi Department of Health SO₂ advisory map and the National Park Service air quality alerts before and during your visit.

My phone has no signal. How do I get help?

Try 911 anyway, then move to higher open ground if it’s safe. Otherwise stay put, stay visible and use your whistle or signal mirror. Rescuers start with the plan you left with someone.

Can I build a campfire on the beach?

Only where it’s allowed. County parks limit open flames to designated fire pits or contained grills, and some ban open fires entirely. Check for burn bans first.

References // Sources

Sources

← All Tutorials NPS Safety Guide ↗