Historical tsunamis · Sep 1, 1923, 2:58 AM UTC
1923 Sagami Bay tsunami
Japan
The tsunami of Sep 1, 1923, 2:58 AM UTC originated near Sagami Bay (Japan).
Key facts
- Date
- Sep 1, 1923, 2:58 AM UTC
- Cause
- Earthquake
- Magnitude
- M7.9
- Depth
- 33 km
- Maximum documented water height
- 13.0 m
- Deaths
- 105,385
- Injuries
- 52,074
- Houses destroyed
- 695,000
- Damage
- US$ 600 million
- Observation records
- 118
- Countries affected
- 4
It was triggered by a magnitude 7.9 earthquake at a depth of 33 km.
The highest documented water height was 13.0 m (Oshima Island, Japan).
118 observation sites in 4 countries are recorded.
Outside the source country, the earliest documented arrival was at Tofino (Clayoquot),British Columbia (Canada) after 13:17 h.
The database records 105,385 deaths.
Houses destroyed: 695,000.
Damage is estimated at US$ 600 million.
Map of observation sites
118Each dot is a documented observation site; colour and size show the observed water height. The triangle marks the source.
Tsunami arrival times
Documented arrival times from the NOAA/NCEI database, showing the earliest recorded location per country. Coverage is incomplete: a country without an entry was not necessarily spared.
- 0:00 hEarthquake (origin) · Sep 1, 1923, 2:58 AM UTC
- 0:02 hJapan · Yokosuka · 1.70 m
- 13:17 hCanada · Tofino (Clayoquot),British Columbia · 0.04 m
21 places with a documented arrival time
Observations by country
| Country | Observation records | Maximum documented water height | Deaths | Earliest arrival |
|---|---|---|---|---|
| Japan | 115 | 13.0 m Oshima Island | 344 | 0:02 h |
 New Zealand | 1 | 0.10 m Lambton Harbour, Wellington | — | — |
 Canada | 1 | 0.04 m Tofino (Clayoquot),British Columbia | — | 13:17 h |
 United States | 1 | 0.03 m Honolulu, Oahu, Hi | — | — |
Highest documented water heights
15 / 118Individual documented observations for this event. Heights come from different measurement types and sources; not every location has a measured height.
| Location / station | Observed height | Distance from source | Country |
|---|---|---|---|
| Oshima Island · Izu-Oshima, Tokyo | 13.00 m | 40 km | Japan |
| Djogashima Island · Kanagawa | 12.00 m | 11 km | Japan |
| Okada · Izu-Oshima, Tokyo | 12.00 m | 37 km | Japan |
| Ainohama · Chiba | 10.30 m | 35 km | Japan |
| Atami · Shizuoka | 9.00 m | 39 km | Japan |
| Ito (Itoshi) · Shizuoka | 9.00 m | 39 km | Japan |
| Kusumi · Shizuoka | 9.00 m | 38 km | Japan |
| North Coast Sagami Bay | 9.00 m | 28 km | Japan |
| Sunosaki · Chiba | 8.10 m | 28 km | Japan |
| Usami · Shizuoka | 7.50 m | 40 km | Japan |
| Ajiro · Shizuoka | 7.20 m | 40 km | Japan |
| Fujiwara · Shizuoka | 7.20 m | 43 km | Japan |
| Shimotaga Niikama · Shizuoka | 7.20 m | 39 km | Japan |
| Kotsubo · Kanagawa | 7.10 m | 22 km | Japan |
| Imam'ura · Shizuoka | 6.00 m | 36 km | Japan |
More tsunamis
Source: NOAA National Centers for Environmental Information (NCEI), Global Historical Tsunami Database. Confirmed events only. Deaths and damage are database estimates; older records are incomplete. Water heights come from different types of observation.