The independent checking and quality inspection of the designs and construction of the Western Harbour Crossing was done by Scott Wilson Kirkpatrick (SWK). The company was also contracted to be the engineer for certification and contractual administration between the Western Harbour Tunnel Company and the Nishimatsu-Kumagai joint venture. SWK sub-contracted the checking of the mechanical and electrical works to Kennedy and Donkin International and the environmental checking to ERM Hong Kong. Company chairman Ron Rakusen said the checkers' role was to ensure design and construction was in accordance with the Government's requirements and standards and also ensure good engineering practices were used. 'Bad engineering practice generally leads to maintenance or operation problems so we check design and construction to look after the interests of the franchisee who will operate the project for 30 years and the Government who will take over the crossing once the franchise expires,' Mr Rakusen said. The designers employed a durability consultant to look at ways of extending the life of the crossing and reducing maintenance costs. He said a project such as the WHC was a 'living thing' with unforeseen problems occurring from time to time, which the constructor would need to resolve. One example was the poor quality of reclaimed land at Sai Ying Pun on the Hong Kong side of the tunnel which required concrete piles to be sunk deeper than originally expected in order to support a number of bridges and approach roads. 'Our responsibility is to ensure the proposals and designs a constructor comes up with to solve an unexpected problem will meet the high standards required for the project and employ good engineering and construction practice,' Mr Rakusen said. The checking process began with a outline design being submitted by the constructor to the Government for approval in principle. The designer then produced a more detailed plan which was independently studied by the checker to make sure any recommended changes had been correctly applied. The checking process then continued throughout the construction stage. 'More than 1,000 detailed designs were checked during the building of the WHC and each stage or 'package' of construction was carefully checked by our on-site inspectors,' Mr Rakusen said. The works checker had to ensure no construction work began before drawings were approved and set environmental standards were complied with. He said checking the environmental aspects of the project involved monitoring dust, disturbance in the harbour, water quality at Shek O, where the tunnel units were cast, debris, litter and noise. Random spot checks were carried out as well as regular checks to make sure the environmental control measures met the contractor's own standards and those of the Government's Environmental Protection Department.