Kumamoto Earthquake Aftermath: Heat and Power Outages Upend Sheltering

A magnitude 7.1 earthquake struck Kumamoto Prefecture on July 28, registering the maximum 7 on Japan’s seismic intensity scale. The tremor, followed by nearly 200 aftershocks by midday on July 29, cut power and water supplies across the region, forcing roughly 10,000 people into evacuation shelters. By the following day, more than 400 facilities were operating, though some remained closed due to the outage, leaving many residents to sleep outside or in their cars.

Temperatures were forecast to reach 40°C, compounding the discomfort. In the city of Yatsushiro, one of the hardest-hit areas, 60 shelters were opened, but residents like 69-year-old Masaharu Tsukada spent the night outdoors because it was “so hot in the shelter.” Others chose their vehicles: a woman in her 50s slept in her car for privacy to take chronic-illness medication unseen, but worried about gasoline running out as she idled the engine for air conditioning.

Why Sleeping in Cars Became a Health Risk—and What That Means for Disaster Response

The Hidden Risk of ‘Economy Class Syndrome’

Medical experts warn that sleeping in a car for prolonged periods can lead to deep vein thrombosis—colloquially called “economy class syndrome”—because sitting still for hours restricts blood flow in the legs. One evacuee described the night as “tough not being able to stretch my legs” and not knowing whether he slept. The 2016 Kumamoto earthquakes had already highlighted this danger, making it a recurring concern in disaster planning.

Heat Becomes a Second Emergency

With shelters lacking air conditioning and daytime highs nearing 40°C, authorities are urging precautions against heatstroke. The combination of extreme heat and immobility raises the risk of dehydration and clotting. Meanwhile, designated parking lots at public facilities allowed overnight car sheltering, but supply shortages and aftershocks leave many without reliable access to water or electricity, stretching local response capacity.

Precautions for Evacuees as Extreme Heat and Aftershocks Continue

  • Move periodically: Health officials advise anyone sheltering in a vehicle to walk around at least once every hour and perform leg stretches while seated to reduce clotting risk.
  • Hydrate and cool down: In the forecast 40°C heat, drinking water frequently and using damp towels or shade is critical. Authorities have warned residents to avoid prolonged sun exposure even inside cars.
  • Use designated parking areas: The city of Kumamoto set up two supervised lots where evacuees can stay in their cars, with plans to deliver water and other supplies to those locations.
  • Monitor aftershocks: Nearly 200 tremors have been recorded, and officials continue to assess structural damage. Staying tuned to local alerts and being ready to move from unsafe sites remains essential.