This study aimed to examine emergency transport times considering closed roads to propose more efficient transport routes to improve the life-saving rate for seriously injured people in Sapporo during an earthquake disaster. Sapporo is the capital of Hokkaido and has a population of approximately 1.97 million as of 2020.

Transport routes were created using publicly available data and a geographic information system (GIS), and the emergency transport times in Sapporo were subsequently calculated. Closed roads were defined as roads in “areas with high liquefaction potential” and “areas with a total house destruction rate ≥20%.”

Closed roads were concentrated in the northeastern part of the city, as were extended emergency transport times, with delays of up to 101 min. Other areas did not experience significant delays.

The emergency transport time was prolonged in areas with closed roads. Triage posts and semi-closed roads were also suggested to affect emergency transport times. To minimize emergency transport times, it is necessary to consider having nurses and doctors ride in ambulances to triage patients, and to coordinate with disaster base hospitals outside of the city to transport seriously injured people.