ENG-1996 — Page 293

LAND, PUBLIC WORKS AND UTILITIES

Operation and Maintenance of the Drainage System

The volume of sewage treated by the department has increased from 385 million cubic metres in 1989 to 750 million cubic metres in 1996, of which 150 million cubic metres received full biological treatment. This was handled by 105 sewage pumping stations and 70 sewage treatment plants throughout the territory.

Since the establishment of the department, the approach to the operation and maintenance of the public drainage system has progressively shifted from crisis. management to preventive maintenance. The efficient maintenance of the drainage infrastructure is essential to ensure the proper and effective disposal of waste and storm water, and to prevent blockages and leaks which cause bad odours, flooding and other nuisances to the public.

The department maintained more than 3 000 kilometres of watercourses, drains and sewers in 1996. Some 50 000 clearance exercises were carried out to remove more than 250 000 cubic metres of silt from drains and watercourses, to keep them free-flowing and their pollution level low. A 24-hour hotline service operated to receive complaints on blocked drains and sewers.

The department also operated an Emergency and Storm Damage Organisation. It was run by staff on a rotational basis and was supported by the department's own labour force and contractors. Its operation ensured that emergency situations were dealt with efficiently. Recurrent expenditure on operations and maintenance in 1996 was $900 million. This sum is increasing steadily.

Geotechnical Engineering

The Geotechnical Engineering Office (GEO) was established after the landslip disasters of the 1970s. The control of geotechnical aspects of construction works to reduce landslip risk continues to be its foremost duty in terms of staff deployed. Geotechnical checks were made on 10 625 design proposals during the year.

The Slope Safety Review Report prepared in 1994 has been implemented in various aspects of GEO's work. These include accelerating the Landslip Preventive Measures (LPM) Programme to increase the annual output of upgrading works for 1996. During 1996, a total of $330 million was spent on the LPM programme. LPM works were completed on 60 government slopes and statutory notices were recommended for 250 private slopes. This represents a five-fold increase over 1995. Preliminary studies were carried out on 3 500 slopes and detailed geotechnical investigations were completed on 480 slopes.

During the year work continued on the 'Systematic Identification and Registration of Slopes in the Territory' (SIRST) project. A new computerised Slope Information System is being compiled. It contains important information on all sizeable man- made slopes and retaining walls in the territory.

The GEO strives for continuous improvement. A new mission statement for the office was drafted, and improvements were made to provide a better service to the community. These include the automation of the GEO Slope Maintenance Hotline in October 1995 to give a 24-hour service to members of the public seeking information on slope maintenance. An educational video on Slope Maintenance has been produced and distributed to organisations concerned with slope maintenance. The

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