Design defects hamper dam`s powerhouse operation
By Ahmad Fraz Khan
2014-05-19
LAHORE: In less than a year since its commissioning in June last year, the Gomal Zam dam in South Waziristan is facing serious problem because of a number of design defects and other related matters.
As a result, it has not been possible to operate the dam`s powerhouse, causing huge losses to the government and Wapda.
Some of the defects have been occurring repeatedly while others are of chronic nature which the contractor has failed to rectify.
This has been stated in a letter marked `top priority` written by the dam`s project manager to his general manager as well as Wapda`s member (water), calling for immediate action on the matter.
The letter said: `Overall seepage from the dam (right and left abutment) is found to be about two cumics per second against the maximum designed seepage of 0.2 cumics. This has not been controlled by the contactor so far.
`Some of the equipment supplied by the contractor are not conforming to the contract requirement. The contractor was required to take remedial measures which have not been done despite repeated requests.
`Some inherent defects in design of the powerhouse scheme have been found and properly reported, but these have not been rectified by the contractor. These equipment were supplied and installed by the contractor without providing the employer`s (Wapda) personnel an opportunity to witness their test at the manufacturer`s premises in China before the shipment. They have also failed to provide collaborative evidence from the users regarding the performance of the equipment.
`Some 34 items of the `punch list` are still pending completion by the contractor despite repeated requests by Wapda. During the nine months of commission (June 15,2013), the contractor has failed complete performance test, contractually required to be performed before the start of trial run operation, undertake remedial measures, rectify defects on a permanent basis and eliminate their reoccurrence. Resultantly, the contractor is considered to be not in a position to fulfil their contractual obligations in the remaining period which expires on June 15 this year.
`Since Feb 26, the contractor is intentionally keeping the powerhouse closed and not allowing Wapda staff to operate it. Because of this the powerhouse was operated only for 1,092 hours, instead of (planned) 5,280 hours, from Sept 1 last year to April 10 this year. This has caused huge losses in terms of power generation and revenue to the government and the Water and Power Development Authority. The contractor has thus failed to prove defect-free performance of all equipment for one year.
In view of this, the project manager recommended, the defect notification period (performance warranty), which expires on June 15, be extended to another year.`These kinds of defects should not occur at this stage,` a former member (water) Wapda said, adding that the project had suffered delays from the beginning.
Some Chinese workers were kidnapped and the contractor ran away. Because of its location in South Waziristan, no-one is ready to go and work there.
Eventually, when Wapda found a contractor, it ran out of funds. Had the USAID not provided funds, the project would have been reeling at somewhere midway to the completion, the former member Wapda said.
But now new issues are cropping up because of design and allied problems.
Although issues like seepage are not new, they do put pressure on the dam`s safety and powerhouse performance.
He said there was an urgent need to solve these problems so that they did not cause any long-term damage to the project.