Telangana government appears to be evading furnishing Medigadda barrage information to NDSA

The NDSA also set 29 October as the deadline for the state to comply, and said it would otherwise go ahead without the information.

Raj Rayasam

Published Oct 28, 2023 | 3:14 PM ⚊ Updated Oct 28, 2023 | 3:44 PM

File photo of the Kaleshwaram project. (Supplied)

Is the Telangana government evading furnishing to the National Dam Safety Authority (NDSA) the information related to the sinking of the piers of the Medigadda (Lakhsmi) barrage of the Kaleshwaram Lift Irrigation Scheme (KLIS)?

Though a high-power committee of NDSA inspected the barrage and sought data from the government, which was supposed to have been handed over to the team before its departure on 26 October, it was withheld.

In a strongly worded letter to the State Dam Safety Organisation (SDSO) and the Telangana Irrigation Department, NDSA Director (Gates Design NW&S) Rahul Kumar Singh directed that the data that the team had sought should be sent within two days.

He also said that non-submission of the information by 29 October would be construed to mean that the project authorities do not have the information, and the committee would proceed accordingly.

Also read: Harish Rao blasts Centre for ‘lies’ in Parliament on Kaleshwaram

The details sought

The high-power committee visited the Medigadda barrage between 23 and 26 October and sought data and inputs on 16 aspects related to the project from the SDSO and project authorities.

The NDSA listed out the data related to several aspects of the Medigadda barrage which had not been furnished yet. They are:

1. Instrumentation data of barrage — piezometer, stress cells, etc — to date,
2. Details of all distress conditions observed in the barrage to date, and relevant drawings of the barrage (provided partially),
3. Relevant sectional drawings of the structure showing settlement,
4. Relevant sectional drawings of structure showing geological profiles,
5. Since the barrage has been added as a specified dam, NDSA-related information may be supplied, such as pre and post-monsoon inspection reports
6. Foundation improvement works, if any,
7. Quality control reports,
8. Third-party monitoring reports, if any,
9. Details on pre-monsoon and post-monsoon cross-section soundings upstream and downstream since the commissioning of the barrage, along with actual retrogression,
10. Relevant clauses of the contract agreement regarding the defect-liability period
11. Completion reports of each block, consisting of all components
12. Photos of bearing conditions both upstream and downstream,
13. Mapping of all cracks in all settled piers,
14. Drawings showing transverse secant pile cut-off under the double pier and the detailing of joining top of the files with the peir,
15. Condition of all gates in block no 7, and
16. Condition of stop-log grooves in block no 7.

Some of the data and information were provided by hand during the visit, but a major part of the information is yet to be handed over to the NDSA authorities.

These include the geological and geotechnical details of foundation strata, especially where settlement has taken place. Categorised, they are:

1. Borehold log details, SPT results, and plate load test results,
2. Design calculations of barrage, hydraulic (surface and subsurface) and stability like safe exit gradient calculation, and maximum and minimum stress under raft for various design conditions, and
3. A physical model study report.

Also read: SC order puts Kaleshwaram capacity increase back on track

Officials explain

Meanwhile, the Irrigation Department officials — apparently with an intention to play down the severity of the damage done to the barrage during the monsoons — said that sinking of piers was common for any barrage built on sand.

The construction of the dam was different from the barrage, which was built on a permeable foundation, they said.

The sinking happens when the sand around the piers is washed away, and this was what happened in Medigadda, they claimed.

The irrigation officials of the state have found damage in six piers (from No:16 to 21). For the restoration work to commence, a coffer dam would be built to prevent water from reaching the work site.

L&T, the contractor for the construction and maintenance of the barrage, will take up the restoration works on its own after consulting the Central Dam Safety Organisation (CDSO).

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