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PUBLIC WORKS AND UTILITIES
begun to develop all these sewerage systems to modern standards. It is intended that all sewage, after primary treatment, should be discharged by submarine outfall into the main tidal currents where it is adequately dispersed. Three treatment plants with submarine outfalls are in use and three outfalls are in partial operation.
In the New Territories sewerage systems are being constructed in the new towns now being developed. A preliminary investigation has started into the sewage treatment facilities which will be re- quired for some of the developing inland centres in the northern New Territories. Progress has continued on a flood control scheme at Yuen Long and all works adjacent to the main town development have been completed. As a result of the severe rainstorm of 12th June, stormwater drains on the north, west and south-west of Hong Kong Island, almost without exception, were overloaded by the heavy run-off or blocked by fallen debris from landslides. Heavy damage to several main stormwater nullahs and culverts resulted, causing widespread flooding, damage to property, deaths and injuries. Temporary and permanent remedial works were immediately put in hand in view of threats of further heavy storms and typhoons. By comparison the drainage systems in Kowloon and the New Territories suffered much less damage.
PORT WORKS
Good progress was maintained on all port works projects during the year. The June rainstorm fortunately had little effect on the port and harbour except to produce an increase in routine dredging necessitated by the large quantities of silt washed into the harbour from nullahs and stormwater drains.
On Hong Kong Island the seawall for the central reclamation scheme was completed, although lack of public dumping pre- vented the completion of the reclamation work. To cater for air- conditioning demands in the central district 51 pumphouses were constructed behind this seawall. The new Outside Harbour Services Pier was completed and put into service in August and a new Government Pier was also completed up to main deck level. At Wan Chai, fill by public dumping continued and was supplemented by dredged material from various sources. Work continued on the seawalls and the ferry pier. Again reclamation was slow, about 10