October 18, 1989 Tsunami: N. California, United States
A tsunami caused by a magnitude 6.9 earthquake began at N. California, United States on October 18, 1989 at 00:04:15 UTC. The water rose as high as 1 meters. Its effects were recorded at 4 places in at least 2 countries. It killed 62 people, counting the earthquake or eruption that caused it.
Where the waves reached
The source (white) and every runup with a place, colored by the water height recorded there. A ring is a runup NCEI marks doubtful.
- Under 1 m
- 1 to 3 m
- 3 to 10 m
- 10 to 30 m
- 30 m and more
- Height not recorded
The tsunami
- Date
- October 18, 1989, 00:04:15 UTC
- Source
- N. California, United States
- Cause
- Earthquake
- Earthquake
- Magnitude 6.9, 19 km deep
- Maximum water height
- 1 m (3.3 ft)
- Runups recorded
- 4
- Tsunami magnitude (Iida)
- -3.3
- Waters
- Ocean
- How certain
- Definite tsunami
- Source location
- 37.036° N, 121.883° W
The toll
- Deaths
- 62 with the earthquake or eruption that caused it
- Injuries
- 3,757 with the earthquake or eruption that caused it
- Damage
- Limited (under about $1 million); $5.6 billion with the earthquake or eruption that caused it
- Houses destroyed
- Many (101 to 1,000) with the earthquake or eruption that caused it
Where the literature gives no number, NCEI records a description on a scale of 1 to 4, printed here in its words. Damage is in millions of US dollars of the year of the event, not adjusted for inflation.
What the record says
NCEI’s account, from the sources it cites.
A magnitude 6.9 earthquake near Loma Prieta about 15 km northeast of Santa Cruz caused extensive damage in the area and in San Francisco. It also generated a small tsunami or tsunamis in Monterey Bay with a maximum recorded amplitude of about 15.7 inches. (reference #1315)
Every runup
Nearest the source first. Heights are above sea level at the time; a tide gauge reads half the wave’s full height.
| Where | Country | Km from source | Water height, m | Inland, m | Measured by | First wave, UTC | Deaths |
|---|---|---|---|---|---|---|---|
| Santa Cruz, CA, CA | United States | 14 | Eyewitness observation of water height | ||||
| Moss Landing, CA, CA | United States | 28 | 1 | Eyewitness observation of water height | |||
| Monterey, CA, CA | United States | 48 | 0.2 | Tide gauge (half the maximum wave height) | day 18, 00:25 | ||
| Fort Denison, Sydney Harbor | Australia | 11,932 | Tide gauge (half the maximum wave height) |
More
Every tsunami in 1989The 1900sTsunamis of United StatesThe earthquakeThis day in weather historyAlerts in force
Sources
Tsunami events and runups from NOAA’s National Centers for Environmental Information, Global Historical Hazard Database, cited as NCEI/WDS, doi:10.7289/V5PN93H7. Public domain. Read 2026-09-24. NCEI tsunami event 2188.