Hyderabad: Irrigation experts, who came to know of building Medigadda barrage on rafter foundation apparently without following adequate safety norms, are of the strong view that the storage capacity should have been less than the present 16 TMC of water.
The experts also expressed doubts on whether the thickness of rafter foundation, that too if built without pile foundation, is sufficient to withstand the higher storage.
“Barrages are usually used as diversion structures and even if it is used for storage the capacity would not be more than 5 TMC,” a former Engineer-in-Chief told Deccan Chronicle.
“If they want to have a higher storage capacity they should have taken more precautions,” he said, adding that the design should be such that flow of water would not take away particles (material used in piers).
Central Water Commission officials were also believed to have questioned the location of the barrage at the present site and inquired if rock surface was not available in the near vicinity. Sources said a lot of precautions were taken in Polavaram though it was being built entirely on rock surface.
The officials carried out 25 metres of jet grouting as extra precaution and it seems they did not take up any such exercise in Medigadda or the two other barrages at Annaram and Sundilla.
The construction giant L&T took a lot of pride in completing the structure in a record time of one year but the irrigation experts suspect that building the structure in a hurried manner led to the damage. In Polavaram, sources said, it took one year to carry out soil testing, grouting and preparing bed to build the structure on it and on the contrary the entire Medigadda barrage was built in one year.
