Historical tsunamis · Oct 11, 1918, 2:14 PM UTC
1918 Puerto Rico: Mona Passage tsunami
USA Territory
The tsunami of Oct 11, 1918, 2:14 PM UTC originated near Puerto Rico: Mona Passage (USA Territory).
Key facts
- Date
- Oct 11, 1918, 2:14 PM UTC
- Cause
- Earthquake and landslide
- Magnitude
- M7.1
- Depth
- 15 km
- Maximum documented water height
- 6.10 m
- Deaths
- 144
- Damage
- US$ 4.0 million
- Observation records
- 20
- Countries affected
- 4
It was triggered by a magnitude 7.1 earthquake at a depth of 15 km.
The highest documented water height was 6.10 m.
20 observation sites in 4 countries are recorded.
Outside the source country, the earliest documented arrival was at Atlantic City, Nj (United States) after 4:46 h.
The database records 144 deaths.
Damage is estimated at US$ 4.0 million.
Map of observation sites
20Each 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) · Oct 11, 1918, 2:14 PM UTC
- 0:24 hUSA Territory · Mayaguez · 1.50 m
- 4:46 hUnited States · Atlantic City, Nj · 0.06 m
3 places with a documented arrival time
Observations by country
| Country | Observation records | Maximum documented water height | Deaths | Earliest arrival |
|---|---|---|---|---|
| USA Territory | 17 | 6.00 m Punta Agujereada | 140 | 0:24 h |
 Dominican Republic | 1 | 0.70 m Santo Domingo | — | — |
| British Virgin Islands (UK Territory) | 1 | 0.70 m Tortola Island | — | — |
 United States | 1 | 0.06 m Atlantic City, Nj | — | 4:46 h |
Highest documented water heights
15 / 20Individual 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 |
|---|---|---|---|
| Punta Agujereada · Pr | 6.00 m | 21 km | USA Territory |
| Punta Higuero · Pr | 5.50 m | 38 km | USA Territory |
| Punta Borinquen · Pr | 4.50 m | 24 km | USA Territory |
| Isla Mona · Pr | 4.00 m | 102 km | USA Territory |
| Rio Culebrinas · Pr | 4.00 m | 33 km | USA Territory |
| Aguadilla · Pr | 3.40 m | 28 km | USA Territory |
| Isabela · Pr | 2.00 m | 28 km | USA Territory |
| Caja de Muertos · Pr | 1.50 m | 115 km | USA Territory |
| Mayaguez · Pr | 1.50 m | 55 km | USA Territory |
| St. Thomas: Krum Bay · Vi | 1.20 m | 239 km | USA Territory |
| Bahia de Boqueron · Pr | 1.10 m | 120 km | USA Territory |
| Rio Grande de Loiza · Pr | 1.00 m | 141 km | USA Territory |
| Cayo Cardona · Pr | 0.75 m | 120 km | USA Territory |
| Santo Domingo | 0.70 m | 292 km | Dominican Republic |
| Tortola Island | 0.70 m | 268 km | British Virgin Islands (UK Territory) |
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.