Reclamation Employees Conduct Dam Safety Training and Dam Inspection on India’s Highest Dam

Written by: Kristine T. Smith

Reclamation’s inspection of Tehri Dam was comprehensive, from the crest of the embankment down to the outlet works.
Reclamation’s inspection of Tehri Dam was comprehensive, from the crest of the embankment down to the outlet works. In June 2016, four Bureau of Reclamation engineers and one engineering geologist from the Technical Service Center, Lakewood, CO, traveled to New Tehri and Rishikesh, India, to provide dam safety principles and programs training to employees at Tehri Hydro Development Corporation India Ltd. (THDCIL), and to inspect Tehri Dam—India's highest dam and the fifth highest dam in the world.

Engineers Chris Danley, David Gillette, Walter Heyder and John Germann, and engineering geologist Bryan Simpson conducted the inspection as part of a comprehensive safety review that included evaluation of the design and a previous analysis of Tehri Dam, similar to what Reclamation does periodically for its own dams. The engineers also provided three days of training to about 50 THDCIL employees, covering topics such as basic principles of embankment dams and concrete dams, potential failure modes for each dam type, monitoring of dam performance, dam inspection and programmatic aspects of dam safety.

THDCIL, a joint venture of the Indian national government and the state government of Uttar Pradesh, operates two large dams on the Bhagirathi River, one of the two main tributaries of the Ganges. One of these dams, Tehri Dam, is an earth-core rockfill dam with a structural height of 854 feet, significantly higher than any Reclamation dam. It has a generating capacity of 1,000 MW, with an additional 1,000 MW pumped-storage powerplant presently under construction. Construction of Tehri Dam was completed in 2006.

Reclamation’s inspection was comprehensive, from the crest of the embankment down to the outlet works. At the end of their visit the engineers presented preliminary findings to THDCIL senior managers. Their preliminary assessment is that Tehri Dam was designed and constructed in close conformance with modern practice.

“The safety of dams training and the comprehensive review of Tehri Dam went very well. We are satisfied with the Bureau of Reclamation team,” said Executive Director H.L. Arora of THDCIL. “All experts are very experienced and have excellent knowledge. We eagerly wait for Reclamation’s report.”

Arora mentioned that THDCIL would like to continue its collaboration with Reclamation by having the engineers perform a similar Comprehensive Review for the second dam in their system. He would also like guidance from Reclamation about other dams that are currently under construction.

Dave Gillette, Reclamation’s project lead for Tehri Dam, says his feelings about the trip are mutual. “I definitely enjoyed the trip to India,” he said. “It was educational for us to see the scale of the Tehri project and design practices in another part of the world, as was the exposure to Indian culture.”

Providing technical assistance, training and inspections abroad have benefited, not only the recipients, but also Reclamation and its staff. Reclamation maintains and enhances its reputation as a lead water resource management agency, while its engineers can work with international water management experts and gain new insight on how other nations are dealing with water resources management.

“This trip allowed our team to see dam design, operation and maintenance practices of another country,” Gillette said. “The team’s knowledge of large dams and spillways was enhanced because the Tehri dam has features and details that are different from Reclamation’s own facilities. Four of the five spillways employ a unique structure for dissipating the energy of the falling water, and there are inspection galleries within the embankment for monitoring settlements.”

The overall consensus, Gillette said, “THDCIL has a very high standard of inspection and monitoring—having staff dedicated to frequent visual inspections and nearly constant readings of many instruments. The knowledge gained could benefit future design and analysis by Reclamation, as we face new challenges and constraints.”

About the Reclamation Employees

Chris Danley, a civil engineer for 37 years with the Technical Service Center’s Inspections Group and current team leader, has been conducting dam safety inspections for more than 29 years for Reclamation and other Department of the Interior agency dams.

John Germann, a mechanical engineer with the Technical Service Center’s Mechanical Equipment Group, has worked for more than 35 years as a field engineer in the operation, maintenance, and rehabilitation of hydro machinery.

David Gillette, a civil/geotechnical engineer with the Technical Service Center’s Geotechnical Engineering Group, has more than 30 years of practical experience in seismic analysis and risk analysis of embankment dams.

Walter Heyder, a civil engineer with the Technical Service Center’s Waterways and Concrete Dams Group, has worked for more than 26 years in design, analysis and inspection of spillways, outlet works and concrete dams, and has been part of Reclamation’s underwater inspection team as a diver for nearly two decades.

Bryan Simpson, an engineering geologist/geotechnical engineer with the Technical Service Center’s Engineering Geology Group, has more than 20 years of experience and offers technical expertise in geologic and geotechnical foundation characterization and analysis related to embankment dams, concrete dams, and other civil projects.

The work completed by Reclamation is funded by THDC India Ltd.

Reclamation staff ended their visit with a boat tour of the reservoir, where they observed various geologic features, such as potential landslides. Because the reservoir was low at the time, staff were able to see the remains of the palace of the King of Tehri in the town of Old Tehri, which was inundated by the reservoir.
Reclamation staff ended their visit with a boat tour of the reservoir, where they observed various geologic features, such as potential landslides. Because the reservoir was low at the time, staff were able to see the remains of the palace of the King of Tehri in the town of Old Tehri, which was inundated by the reservoir.

Reclamation engineers provided three days of training to about 50 THDCIL employees, covering topics such as basic principles of embankment dams and concrete dams, potential failure modes for each dam type, monitoring of dam performance, dam inspection and programmatic aspects of dam safety.
Reclamation engineers provided three days of training to about 50 THDCIL employees, covering topics such as basic principles of embankment dams and concrete dams, potential failure modes for each dam type, monitoring of dam performance, dam inspection and programmatic aspects of dam safety.

Published on October 05, 2016