Geotechnical News • June 2018
31
GEOHAZARDS
Dam/incident
Year
Location
Fatalities Details
2
Lake Toxaway Dam
1916
Transylvania County,
North Carolina
0
Heavy rains caused the dam to give way.
Dam was later rebuilt in the 1960s.
Sweetwater Dam
1916
San Diego County,
California
0
Over-topped from flooding.
Lower Otay Dam
1916
San Diego County,
California
14
Over-topped from flooding.
Gleno Dam
1923
Province of
Bergamo, Italy
356
Poor construction and design.
Llyn Eigiau dam and the
outflow also destroyed
Coedty reservoir dam.
1925
Dolgarrog, North
Wales, UK
17
Contractor blamed cost-cutting in con-
struction but 25” of rain had fallen in
preceding 5 days. This was the last dam
failure to cause death in the UK to date
(2018).
St. Francis Dam
1928
Santa Clarita,
California, Los
Angeles County,
United States
600
Geological instability of canyon wall
combined with human error that assessed
developing cracks as “normal” for a dam
of that type.
Secondary Dam of Sella
Zerbino
1935
Molare, Province of
Alessandria, Italy
111
Geological unstable base combined with
flood.
Nanty Gro Reservoir
in
Wales
1942
Nanty Gro
Valley, Wales
0
Destroyed during preparation for Opera-
tion Chastise in World War II.
Eder, Möhne Dams
1943
Eder Valley, Ruhr, Ger-
many
70
Destroyed by bombing during Operation
Chastise
in World War II
.
Vega de Tera
1959
Ribadelago, Spain
144
Malpasset
1959
Côte d’Azur, France
423
Geological fault possibly enhanced by
explosives work during construction.
Panshet Dam
1961
Pune, India
~1,000 Dam wall burst due to precipitation.
Baldwin Hills
Reservoir
1963
Los Angeles,
California,
United States
5
Subsidence caused by over-exploita-
tion of local oil field.
Spaulding Pond
Dam(Mohegan Park)
1963
Norwich,
Connecticut,
United States
6
More than $6 million estimated damages.
Vajont Dam
1963
Italy
2,000
Strictly not a dam failure, since the dam
structure did not collapse and is still
standing. Filling the reservoir caused
geological failure in valley wall, leading
to 110 km/h landslide into the lake; water
escaped in a seiche over the top of dam.
Mina Plakalnitsa, (Vratsa 1966
Vratsa, Bulgaria
107
A tailings dam at Plakalnitsa copper
mine near the city of Vratsa failed. A
total 450,000 cubic meters of mud and
water inundated Vratsa and the nearby
village of Zgorigrad, which suffered
widespread damage. The official death
toll is 107, but the unofficial estimate is
around 500 killed.
