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Cross Harbour Pipe Line.
This work forms the very valuable connecting link between Kowloon and Hong Kong which enables water from the mainland to be supplied to Hong Kong.
Investigations were commenced in 1924, when a survey was made of the con- tour and nature of the harbour bed on a line between Nathan Road, Kowloon, and Jackson Road, Hong Kong.
The information obtained from 15 borings and 56 prickings was correlated, and submitted in 1925, through the Crown Agents for the Colonies, to Consulting Engineers in England who prepared a scheme for laying two 18" Cast Iron mains across the harbour. Contract documents were prepared by the Consulting Engineers and tenders were called for from Contractors in England. Owing, however, to the serious trade disorganization then prevailing in Hong Kong and South China the work was postponed, and it was not continued until the beginning of 1929 when Mr. Henderson was deputed to proceed to England to place personally before the Colonial Office and Consulting Engineers a scheme prepared by him. In May, 1929, the Consulting Engineers approved of Mr. Henderson's scheme, with slight modifica- tions, and orders for the necessary pipe work and specials were placed in England on June 28th, 1929. Delivery of these commenced in Hong Kong on September 18th, 1929.
During this period arrangements involving the preparation of the harbour bed and the casting of heavy concrete anchor blocks were proceeded with in Hong Kong and on Mr. Henderson's return to the Colony in September preparations were made for laying the pipes and the construction of a pipe assembly yard for the fabrication of short pipes into 100 feet lengths. The Contract for laying was signed on October 8th, 1929, and a commencement was made with the welding of 100 foot lengths on October 13th.
Although all possible arrangements for laying the pipe were completed by October 23rd, the actual laying was not commenced until December 17th, 1929, owing to the late arrival of Ball and Socket Joints from England.
The laying of the submarine section was completed on February 17th, 1930, having taken 57 working days.
The connections between the submarine and land sections were completed on February 23rd, 1930, and from that date to March 31st, when the pipe line was officially opened, major protective works and general testing of the pipe line were carried out. Further protective works were found necessary during the period of maintenance of the contract, and these were completed by the end of May, 1930.
The operations of jointing the pipes on the harbour bed were carried out by two Northern Chinese divers, supplied by the laying contractor, under the super- vision of the Government diver.
The position of the Hong Kong terminal of the pipe line was changed from Jackson Road to Queen's Pier, and the line of the harbour pipe was altered ac- cordingly. This obviated the necessity of building a new pier at Jackson Road.
The pipe line consists of lap welded steel pipes, 12.265" internal diameter and 7/16′′ thick, in random lengths of 18′ to 22', having tapered spigots and sockets 8" long and welded joints.
The inside and outside of the pipes are coated with bitumen, the outside being doubly wrapped with hessian impregnated with bitumastic solution.
Lengths of about 100' were fabricated at the Pipe Assembly Yard, situated on the sea wall near Arsenal Street, and consisted generally of spigot and socket pipes. with welded joints, the ends of the 100 foot lengths being fitted with male and female