ENG-1995-07-05 — Page 2

HONG KONG LEGISLATIVE COUNCIL — 5 July 1995 5063 Preventive Maintenance

7. The drainage system requires regular inspection, desilting and repair to ensure that it functions properly. A preventive maintenance programme is drawn up each year to ensure that problematic drains are inspected before and during the rainy season. Any chokage found will be cleared and defects rectified immediately. In 1994/95, territory-wide, a total of 750 km of drains (including streamcourses) were inspected and 260 km were desilted. A total of $65 million was spent on maintaining the drainage system of the territory. In addition, a special programme of inspecting flood control installations, such as flood water pumping stations and local flood warning systems, is conducted annually to ensure the installations will be fully operational in times of rainstorm.

8. Experience has shown that many minor floodings are caused not by inadequacy of the main drainage system but because rain water cannot get into the system. This is often because of rubbish blocking the gully inlets and more effort is being made to keep road gullies clear of rubbish. As a further measure, at appropriate locations, additional road gullies are being provided to get water into the drainage system more effectively.

Surveillance

9. Some localized flooding is caused by activities connected with construction sites. Problems arise as a result of construction waste blocking the drains, inadequate provision of temporary drainage, temporary works obstructing flow in the drainage system or damage caused to the drains. Before the rainy season, reminders will be sent to engineers, authorized persons, consultants and contractors in charge of construction sites requesting their co-operation in exercising strict control of their construction activities.

LEGISLATIVE AND INSTITUTIONAL MEASURES

10. Uncontrolled developments in the past have exacerbated the flooding problems because of their adverse drainage impacts in increasing flood flow, reducing flood storage and, in some cases, obstructing flood flow. To prevent further deterioration of the situation the Drainage Services Department has been providing advice to the Planning Department in