KARACHI, Nov 5 Flaws have surfaced in the Defence Housing Authority's new drainage system laid at a high cost, and the removal of the defects and making it functional properly will cost twice as much, it has been learnt.

The last rains exposed the faults in the project, completed before the downpour at a cost of around Rs3 billion. Sources say the amount is four times of what was initially estimated, as components of the project were left incomplete and more funds, almost equal to the original project cost, were spent.

And now almost twice the amount of the initial cost was needed to construct the parts that had been omitted earlier if it had to function properly, the sources told Dawn.

They said that increasing the scope of work and cost by more than 15 per cent or omitting parts of the project after the contract had been awarded was against the Public Procurement Regulatory Authority rules and it was a fit case for the PPRA to examine if any violation of rules had taken place.

They said the flaws were revealed following the last rains when many areas remained inundated, exposing the DHA's claims that all rainwater would drain soon after the rain stopped.

The sources said that the shortcomings of the system were pointed out by the same consultants who had planned it and now they wanted additional funds to make the project effective.

They said that at the time of launching of the work for the drainage system, the DHA had said that it would cost around Rs700 million. However, when it was completed, the DHA said over Rs2.2 billion had been spent on it. In addition, between Rs600 million and Rs700 million was spent on the roads that had been damaged by the laying of the drainage network. The cost was borne jointly by the DHA and the Cantonment Board Clifton.

Sometime back, the DHA's drainage system consultants at a briefing about the functioning of the drainage system had disclosed that a number of interceptor drains were omitted from the original design owing to a paucity of funds due to which rainwater accumulated in parts of DHA Phases IV and VII during the last rains.

They presented an augmented design plan for addressing the problem areas identified during the rains. The improvement plan includes construction of additional interceptor drains and re-profiling of a few roads. This project would cost almost Rs1.5billion, the sources said.