Irrigation tests stalled by tech problems at Medigadda
SOS sent to CWPRS for drilling expert
Hyderabad: The exercise to determine the nature and the condition of the river bed under the Medigadda barrage continues to pose challenges to the irrigation department, which has said that it was unable to drill boreholes on the barrage’s causeway and spillway sections due to ‘certain technical problems’. The department has sent an SOS to the Central Power and Water Research Station (CPWRS), Pune, asking for urgent help.
The latest challenge related to drilling boreholes, the chief engineer of Ramagundam circle of the irrigation department said in a letter on Thursday to CWPRS, and urged the organisation to “arrange a drilling expert to visit the site to advise on the issue as per the site condition at the earliest.”
Drilling of boreholes is part of the required investigations suggested by the National Dam Safety Authority (NDSA). The irrigation department gave the contract for conducting the studies to the Pune-based institute. Unless all the studies are completed and the data analysed, no design can be prepared for taking up repairs at the barrage which suffered significant damage with one of its blocks cracking and sinking into the riverbed in October 2023.
Sources said that earlier too when boreholes were sought to be drilled to reach the river bed under the foundations of the Medigadda barrage, similar problems were encountered. “The riverbed is sandy and core samples drawn from the drilling collapse. If the core sample cannot maintain its column structure then nothing can be learnt from a pile of sand,” a source familiar with these problems encountered at the site when boreholes were sought to be drilled last year, said.
One possible way to draw intact core samples could be using a casing inside the drill, but that would interfere with the integrity of the core sample as the material could be compressed inside the casing. Such core samples will not serve any purpose to study the river bed strength under the barrage, a senior engineer with experience in irrigation project construction said.
The irrigation department is, meanwhile, under increasing pressure to complete the studies, before the summer ends and the rain starts when the flows in the Godavari river will increase and no work can be done until next year’s summer.
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Centre in January placed Medigadda barrage in Category-I of danger level;
Parliament informed that the barrage could experience ‘failure’ if the ‘most serious deficiencies’ are not addressed;
Centre said Telangana was told to implement preventive and mitigating measures recommended by the NDSA to ensure Medigadda barrage safety.