A senior official apologised yesterday for failing to seek endorsement for a $233 million design change to the Convention and Exhibition Centre extension to stop water coming in. Secretary for Trade and Industry Chau Tak-hay also admitted his error in not reporting the design revision to legislators. At a Public Accounts Committee hearing on the Auditor's Report, Mr Chau expressed regret for a procedural oversight. The Director of Audit, Dominic Chan Yin-tat, asked why the new design had not been submitted to the project control committee for an endorsement. 'Concerning this omission, I would like to take all the responsibility and am more than willing to apologise to all the concerned parties and public,' said Mr Chau, the then project chief. Secretary for the Treasury Denise Yue Chung-yee maintained no approval from legislators was required for the additional funding. She said the extra money had come from the self-generated revenue of the Trade Development Council rather than public funds. Ms Yue admitted they should have updated the Finance Committee on the change of design. 'There was an oversight on the part of the administration. We only submitted one progress report to the Finance Committee,' she admitted. While there were reservations about the long-term waterproofing of the roof, which contributed in part to the extra cost, the centre denied water leaked through it. The centre's chief executive, Niels Kraunsoe, said it was the drainage system formed within the roof that led to water dripping. 'These drainpipes carry 100 tonnes of water per minute during heavy rain,' he said. The Frontier's Emily Lau said: 'Whether it is a roof leak or pipe leak or whatever, it is a leak. What we are interested in is why there are so many leaks.' Mr Kraunsoe insisted that water dripping was a phenomenon common to all buildings.