Dam failure

The reservoir emptying through the failed Teton Dam

A dam is a barrier across flowing water that obstructs, directs or slows down the flow, often creating a reservoir, lake or impoundments. Most dams have a section called a spillway or weir over which, or through which, water flows, either intermittently or continuously, and some have hydroelectric power generation systems installed.

Dams are considered "installations containing dangerous forces" under International Humanitarian Law due to the massive impact of a possible destruction on the civilian population and the environment. Dam failures are comparatively rare, but can cause immense damage and loss of life when they occur.

Main causes of dam failure

International special sign for works and installations containing dangerous forces

Common causes of dam failure include:

• Sub-standard construction materials/techniques (Gleno Dam)
• Spillway design error (South Fork Dam, near failure of Glen Canyon Dam)
• Geological instability caused by changes to water levels during filling or poor surveying (Malpasset).
• Sliding of a mountain into the reservoir (Vaiont Dam – not exactly a dam failure, but caused nearly the entire volume of said reservoir to be displaced and overtop the dam)
• Poor maintenance, especially of outlet pipes (Lawn Lake Dam, Val di Stava Dam collapse)
• Extreme inflow (Shakidor Dam)
• Human, computer or design error (Buffalo Creek Flood, Dale Dike Reservoir, Taum Sauk pumped storage plant)
• Internal erosion, especially in earthen dams.

Deliberate dam failure

A notable case of deliberate dam failure (prior to the Humanitarian Law rulings) was the British Royal Air Force Dambusters raid on Germany in World War II (codenamed "Operation Chastise"), in which three German dams were selected to be breached in order to impact on German infrastructure and manufacturing and power capabilities deriving from the Ruhr and Eder rivers. This raid later became the basis for several films.

List of major dam failures

Dam/incident	Year	Location	Details
Marib Dam	575	Sheba, Yemen	Unknown (possibly neglect)
Pantano de Puentes	1802	Lorca, Spain	608 deaths, 1800 houses and 40000 trees destroyed[1]
Dale Dike Reservoir	1864	South Yorkshire, England, United Kingdom	Defective construction, small leak in wall grew until dam failed.
South Fork Dam	1889	Johnstown, Pennsylvania, United States	Blamed locally on poor maintenance by owners; court deemed it an "Act of God". Followed exceptionally heavy rainfall. Caused Johnstown flood.
Walnut Grove Dam	1890	Wickenburg, Arizona Territory, United States	Heavy snow and rain following public calls by the dam's chief engineer to strengthen the earthen structure.
McDonald Dam	1900	Texas, United States	Extreme current caused failure.
Austin Dam	1911	Austin, Pennsylvania, United States	Poor design, use of dynamite to remedy structural problems.
Desná Dam	1916	Desná, Austria-Hungary (now Czech Republic)	Construction flaws caused the dam failure
Lake Toxaway Dam	1916	Transylvania County, North Carolina	Heavy rains caused the dam to give way. Dam was later rebuilt in the 1960s
Sweetwater Dam	1916	San Diego County, California	Over-topped from flooding
Lower Otay Dam	1916	San Diego County, California	Over-topped from flooding; 40 deaths
Gleno Dam	1923	Province of Bergamo, Italy	Poor construction and design
Llyn Eigiau dam and the outflow also destroyed Coedty reservoir dam.	1925	Dolgarrog, North Wales, UK	Contractor blamed cost-cutting in construction but 25" of rain had fallen in preceding 5 days. This was the last dam failure to cause death in the UK to date (2010).
St. Francis Dam	1928	Valencia, California, Los Angeles County, United States	Geological instability of canyon wall that could not have been detected with available technology of the time, combined with human error that assessed developing cracks as "normal" for a dam of that type.
Nanty Gro Reservoir in Wales	1942	Nanty Gro Valley, Wales	Destroyed during preparation for Operation Chastise in World War II.
Eder, Möhne Dams	1943	Eder Valley, Ruhr, Germany	Destroyed by bombing during Operation Chastise in World War II.
Vega de Tera	1959	Ribadelago, Spain	144 deaths[2][3]
Malpasset	1959	Côte d'Azur, France	Geological fault possibly enhanced by explosives work during construction; initial geo-study was not thorough.
Baldwin Hills Reservoir	1963	Los Angeles, California, United States	Subsidence caused by over-exploitation of local oil field
Spaulding Pond Dam (Mohegan Park)	1963	Norwich, Connecticut, United States	6 deaths, more than $6 million estimated damages
Vaiont Dam	1963	Italy	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. Valley had been incorrectly assessed stable.
Mina Plakalnitsa, (Vratsa)	1966	Vratsa, Bulgaria	A tailings dam at Plakalnitsa copper mine near the city of Vratsa failed. A total 450,000 cu m 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. [4]
Buffalo Creek Flood	1972	West Virginia, United States	Unstable loose constructed dam created by local coal mining company, collapsed in heavy rain
Canyon Lake Dam	1972	South Dakota, United States	Flooding, dam outlets flooded with debris.
Banqiao and Shimantan Dams	1975	China	Extreme rainfall beyond the planned design capability of the dam
Teton Dam	1976	Idaho, United States	Water leakage through earthen wall, leading to dam failure.
Laurel Run Dam	1977	Pennsylvania, United States	Heavy rainfall and flooding that over-topped the dam.
Kelly Barnes Dam	1977	Georgia, United States	Unknown, possibly design error as dam was raised several times by owners to improve power generation.
Machchu-2 Dam	1979	Gujarat, India	Heavy rain and flooding beyond spillway capacity.
Wadi Qattara Dam	1979	Benghazi, Libya	Flooding beyond discharge and storage capacity damaged the main dam and destroyed the secondary dam in the scheme.
Lawn Lake Dam	1982	Rocky Mountain National Park, United States	Outlet pipe erosion; dam under-maintained due to location
Tous Dam	1982	Valencia, Spain
Val di Stava Dam collapse	1985	Italy	Poor maintenance and low margin for error in design; outlet pipes failed leading to pressure on dam.
Peruća Dam detonation	1993	Croatia	Not strictly a dam failure as there was a detonation of pre-positioned explosives by retreating Serb Forces.
Saguenay Flood	1996	Quebec, Canada	Problems started after two weeks of constant rain, which severely engorged soils, rivers and reservoirs. Post-flood enquiries discovered that the network of dikes and dams protecting the city was poorly maintained.
Meadow Pond Dam	1996	New Hampshire, United States	Design and construction deficiencies resulted in failure in heavy icing conditions
Opuha Dam	1997	New Zealand	Heavy rain during construction caused failure, dam was later completed
Vodní nádrž Soběnov	2002	Soběnov, Czech Republic	Extreme rainfall during the 2002 European floods
Ringdijk Groot-Mijdrecht	2003	Wilnis, Netherlands	Peat dam became lighter than water during droughts and floated away
Hope Mills Dam	2003	North Carolina, United States	Heavy rains caused earthen dam and bank to wash away
Big Bay Dam	2004	Mississippi, United States	A small hole in the dam, grew bigger and eventually led to failure.
Camará Dam	2004	Brasil
Shakidor Dam	2005	Pakistan	Sudden and extreme flooding caused by abnormally severe rain, 70 deaths
Taum Sauk reservoir	2005	Lesterville, Missouri, United States	Computer/operator error; gauges intended to mark dam full were not respected; dam continued to fill. Minor leakages had also weakened the wall through piping.
Campos Novos Dam	2006	Campos Novos, Brazil	Tunnel collapse
Gusau Dam	2006	Gusau, Nigeria	Heavy flooding
Ka Loko Dam	2006	Kauai, Hawaii	Heavy rain and flooding. Several possible specific factors to include poor maintenance, lack of inspection and illegal modifications.
Lake Delton	June 9th, 2008	Lake Delton, Wisconsin	Failure due to June 2008 Midwest floods.
Koshi Barrage	2008	Kusha, Nepal	Heavy rain.
Situ Gintung Dam	2009	Tangerang, Indonesia	Poor maintenance and heavy monsoon rain
Kyzyl-Agash Dam	2010	Kazakhstan	Heavy rain and snowmelt
Hope Mills Dam	2010	North Carolina, United States	Sinkhole caused dam failure
Delhi Dam	2010	Iowa, United States	Heavy rain, flooding.
Ajka alumina plant accident	October 4, 2010	Hungary	Failure of concrete impound wall on alumina plant tailings dam.
Kenmare Resources tailings dam	October 8, 2010	Mozambique	Failure of tailings dam at titanium mine.
Fujinuma Dam	March 11, 2011	Japan	Failed after 2011 Tōhoku earthquake.

References

1. ^ La rotura del pantano de Puentes
2. ^ [1]
3. ^ 40 años de la tragedia de Ribadelago, en la que murieron 144 personas (Spanish)
4. ^ http://zgorigrad.com/tragediata

External links

• A list of dam failures and incidents in the United States Dam Safety.org
• Chronology of major tailings dam failures from 1960 WISE Uranium Project
• Chanson, H. (2009) Application of the Method of Characteristics to the Dam Break Wave Problem Journal of Hydraulic Research, IAHR, Vol. 47, No. 1, pp. 41–49 (DOI: 10.3826/jhr.2009.2865) (ISSN 0022-1686). Available as a pdf at [2]

See also

• Levee
• List of hydroelectric power station failures
• Grout curtain
• Structural failure
• Hydroelectric power station failures
• Hydroelectricity