Dams Causing Earthquakes: Capacity Building in Dam Safety Areas Under Dam Rehabilitation (Download PDF)

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Pressure applied to often-fragile geological structures by the vast mass of water impounded by a big dam can give rise to earthquakes. Landslide at the Vaiont dam in Italy in 1963 triggered off by seismic activity, killed 2, 000 people.

Image of Dams Causing Earthquakes

Image of Dams Causing Earthquakes

Image of Dams Causing Earthquakes

History of Earthquakes at Dams

First seismic activity was imputed to a reservoir in California in the late 1930s in Lake Mead, which was impounded by the Boulder dam in 1935- main shock occurred four years afterwards preceded by a number of smaller shocks.

Since then, major earthquakes have occurred at four large reservoirs causing deaths, injuries, and a vast amount of damage to houses and other structures

  • At Hsinfengkiang in China in 1962 (magnitude 6.1)

  • At Kariba, in Rhodesia in 1963 (magnitude 5.8)

  • At Kremasta in Greece in 1966 (magnitude 6.3)

  • At Koyna, in India in 1967 (magnitude 6.5)

  • At Koyna and Hsinfengkiang, the dams themselves were damaged causing huge flood.

  • Landslide at the Vaiont dam in Italy in 1963 triggered off by seismic activity, killed 2, 000 people.

Fourth World Congress on Earthquake Engineering, in Santiago, Chile, in January 1969

  • Focused on relationship between large dams and earthquakes with Professor Jean Pierre Rothe, presenting his famous paper ‘Man-Made Earthquakes’

  • Different incidents when studied together establish strong relation between occurrence of an earthquake and presence of large man-made lake in its immediate vicinity.

Case Study 1: The Koyna Dam, India

  • The Koyna Dam is 103 meters high with maximum volume of 2, 780 million cubic meters.

  • Filling started in 1962 and ended in 1964 when the reservoir was less than half filled.

  • In 1963, the frequency of the shocks increased greatly, and their epicenters were all found to be either in the neighborhood of the dam or under the reservoir.

  • In 1964, the volume of the water in the reservoir was brought up to 2 Gm3.

  • On 13th September, 1967, two important shocks were felt, the first of which caused great damage to the village of Koynanagar, killing 177 people and injuring 2, 300 others.

  • Numerous after-shocks with epicentre in the vicinity of the dam or directly under the reservoir itself occurred.

  • Deccan plateau, where Koyna dam was built, is uniformly covered by Basaltic rocks which makes the “this shield” one of the least seismic of the pre-Cambrian areas of the world with no known faults.

  • Thus the filling of the reservoir was largely help responsible for the two major shocks of September and December 1967.

Case Study 2: The Kariba Dam

  • Kariba Dam is a double curvature concrete arch dam in the Kariba Gorge of the Zambezi river basin between Zambia and Zimbabwe

  • The Kariba dam is 125m high, and the reservoir covers an area of 6, 649 square kilometers and contains 175 Gm3 of water.

  • The lake overlies a region formed from sediments of the Karoo and of volcanic lava dating from the upper Carboniferous and Jurassic.

  • Prior to the construction of dam, the Zambezi valley was considered aseismic- not a single epicenter for the region appears in the relevant UNESCO catalogue

  • The filling of the lake started in December 1958, and completed in August 1963.

  • Twenty-two shocks occurred in 1959 and 15 in 1961- one attained a magnitude of 4.

  • Thereafter, seismic activity increased rapidly- 63 shocks were registered in March, 1962, and 61 were felt in the first seven months of 1963.

  • When the lake filled in 1963, a series of strong shocks occurred with ten epicenters situated in the deepest part of the lake; the strongest had a magnitude of 6.1.

Central Water Commission (CWC) MoUs with IIT Roorkee and MNNIT Allahabad for Dam Rehabilitation Support

Central Water Commission (CWC) signed MoUs with IIT Roorkee and MNNIT Allahabad for dam rehabilitation support in areas of dam safety through World Bank assisted Dam Rehabilitation and Improvement Project (DRIP).

Project Scope Dam Rehabilitation and Improvement Project

Scope includes:

  • Strengthening the testing laboratories

  • Enhancing analytical capabilities

  • Exposure visits to best global institutions

  • Ground exposure to dam safety concerns to the faculty of these institutions

Ongoing Activities on Dam Safety and Rehabilitation

  • DRIP is assisting rehabilitation of 225 dams in seven States experiencing different levels of distress.

  • DRIP provides technical support for the investigating dam conditions and supporting rehabilitation efforts.

  • As the project lacks labor and technical expertise Government decided to enhance the capability of selected premier academic institutes in dam safety areas.

  • The institutes are thus expected to carry out field investigations and material testing, and provide training and consulting in dam rehabilitation efforts.

  • Project also envisages institutional strengthening- capacity building of all partners agencies and premier academic institutions in dam safety areas through proper training, global partnership, and on ground exposure.

Background on Dam Safety (Earthquakes and Dams)

  • CWC already signed MoUs with IIT Madras, IISc Bangaluru, NIT Calicut, and NIT Raurkela for procurement of specified equipment and software for enhancing their testing and modeling capabilities.

  • CWC facilitated signing of MoUs by Madhya Pradesh Water Resources Department (MPWRD) and UJVN Limited (UJVNL), Uttarakhand with the Earthquake Engineering Department of IIT Roorkee for assisting MPWRD and UJVNL in establishment of seismic instruments for generating seismic event report having an intensity greater than 4.0.

  • Government has already linked data collection, processing, monitoring, analysis, interpretation of the State Dam Seismological Network (SDSN) data with Indian Dam Seismological Network (IDSN) for strengthening existing seismological network.

- Published/Last Modified on: October 29, 2017

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