PWSC(97-98)45
For discussion
on 3 September 1997

ITEM FOR PUBLIC WORKS
SUBCOMMITTEE OF FINANCE COMMITTEE

HEAD 705 - CIVIL ENGINEERING
Public Safety - Landslip prevention
51BL - Systematic identification and registration of slopes

Members are invited to recommend to Finance Committee -

1. an extension in the project scope of 51BLfor the identification and registration of an additional 10 000 man-made slopes¹in the Territory; and

2. an increase in the approved project estimate of 51BL from $99.3 million by $29.3 million to $128.6 million in money-of-the-day prices.

PROBLEM

The number of man-made slopes in the Territory requiring registration is estimated to be 60 000, which is 10 000 more than the existing project scope of 50 000 slopes. The approved project estimate of 51BL is insufficient to cover the additional works we wish to incorporate in the project.

PROPOSAL

2. The Director of Civil Engineering, with the support of the Secretary for Works, proposes to increase the approved project estimate of 51BL from $99.3 million by $29.3 million to $128.6 million in money-of-the-day (MOD) prices to employ additional consultants ' professional and technical staff for the identification and registration of 10 000 more man-made slopes and to meet related expenses.

PROJECT SCOPE AND NATURE

3. The existing project aims to compile a comprehensive Catalogue of Slopes involving about 50 000 man-made slopes and comprises -

1. a systematic search for and identification of about 50 000 slopes in the Territory that need registration, using Aerial Photograph Interpretation techniques;

2. an inspection programme of the slopes identified, which includes examining the slope conditions, recording the relevant information and recommending any follow-up actions together with a pilot study for definitive determination of maintenance responsibility in two areas, namely Magazine Gap Road and Sai Sha Road, covering about 400 slopes; and

3. the establishment of a computerised, easy-to-understand Catalogue of Slopes on a local area network within the Civil Engineering Department.

4. The current proposal aims to extend the above scope for compiling a comprehensive Catalogue of Slopes involving about 60 000 man-made slopes.

JUSTIFICATION

5. Up to early 1996, priority for mapping was given to the main urban areas of Hong Kong Island and Kowloon and the New Towns in the New Territories. The figure of 50 000 slopes was based on the intensity of slopes found in these areas. Subsequent mapping in older village areas, outlying islands and along roads in the New Territories showed that the intensity of slopes was greater than anticipated. By late June 1997, approximately 90% of the Territory has been mapped and 50 000 slopes identified, with about 34 000 slopes inspected and catalogued. Following completion of mapping of a large proportion of the Territory and having a better understanding of what remains to be done, we estimate that the total number of slopes that should be identified and catalogued will be in the region of 60 000. In other words, we need to identify and inspect a further 10 000 man-made slopes.

6. Having regard to the importance of public safety, we plan to complete the compilation of the Catalogue of Slopes by September 1998. To meet this target date, we need an urgent increase in the project estimate to enable engagement of more consultants' staff resources to deal with the additional workload. The additional funds will cover increased consultancy fees, additional equipment and other related expenses such as transport costs for site inspections by the consultants ' staff.

7.Enclosure 1 gives a detailed comparison of the original and revised estimates of consultants' fees. Enclosure 2 gives a detailed breakdown of the approved and revised project estimates and the reasons for the proposed increase in the project estimate.

FINANCIAL IMPLICATIONS

8. We estimate the revised project estimate of the project to be $128.6 million in MOD prices (see paragraph 9 below) which is made up as follows -

9. The actual expenditure up to March 1997 is $66.8 million. Subject to approval, we will phase expenditure as follows -

We derive the MOD estimate on the basis of the Government ' s forecasts of trend labour and construction prices over the period between 1997 and 1999.

10. The proposed extension in project scope and increase in the approved project estimate will raise the annually recurrent expenditure from $200,000 to $300,000 for maintenance of computer hardware and software.

PUBLIC CONSULTATION

11. As the revised scope of the project is mainly due to the increase in the estimate of the number of slopes in the Territory for identification and registration, we consider that we do not require any public consultation.

LAND ACQUISITION

12. The project does not require land acquisition.

ENVIRONMENTAL IMPLICATIONS

13. The proposed study will lead to the compilation of a Catalogue of Slopes. As such, there is no direct environmental impact arising from the study.

BACKGROUND INFORMATION

14. On 1 July 1994, the Finance Committee approved the upgrading of this project to Category A at an estimated cost of $41.8 million (at December 1993 prices) for the systematic identification and registration of 30 000 man-made slopes. We commenced work on this project in 1994.

15. On 8 March 1996, the Finance Committee approved an extension in the project scope of 51BL for the identification and registration of an additional 20 000 man-made slopes and an increase in the approved project estimate from $41.8 million by $57.5 million to $99.3 million.

16. We plan to complete the whole project by September 1998.

Works Bureau
August 1997

(KK219)

1-- Man-made slopes fall into three categories : Cut slopes (including associated retaining walls) and retaining walls of more than three metres in height; fill slopes (including associated retaining walls) of more than five metres in height; and fill slopes (including associated retaining walls) of less than five metres in height which pose a direct risk to life in the event of failure.

2-- These are actual expenditure incurred from 21 July 1994 to 31 March 1997 for the project tasks involving the identification of about 47 000 slopes, inspection of about 30 000 slopes and the completion of the pilot study for definitive determination of maintenance responsibility as part of the project scope mentioned in paragraph 3(b) above and the preparation of the feasibility study report for the establishment of the computerised Catalogue of Slopes.

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Enclosure 1 to PWSC(97-98)45

Comparison of the Approved and Revised Project Estimates for Consultants ' Fees by Man Months

Notes

1. A multiplying factor of 2.5 is applied to the average MPS point to arrive at the full staff costs including the consultants ' profit and overheads (excluding the consultants ' office accommodation as the consultants ' staff will be working in Geotechnical Engineering Office of the Civil Engineering Department).

2. The average estimated cost per professional man month for items (a) and (b) is about equivalent to an Engineer on MPS point 43 ( $62,855 p.m. at 1.4.96).

3. The average estimated cost per professional man month for item (c) is about equivalent to an Engineer on MPS point 38 ( $50,755 p.m. at 1.4.96).

4. The average estimated cost per technical man month for items (a) and (b) is about equivalent to a Technical Officer on MPS point 21 ( $23,725 p.m. at 1.4.96).

5. The average estimated cost per technical man month for item (c) is about equivalent to a Technical Officer on MPS point 11 ( $14,245 p.m. at 1.4.96).

6. The figures given above are based on estimates prepared by the Director of Civil Engineering. We will only know the actual man months and actual fees when we have selected the consultant.

(KK219)

* We convert the approved project estimate (Dec 94) to approved project estimate (Dec 96) by using the 9%trend labour and construction index for the year 1995 and the 8% trend labour and construction index for the year 1996. No inflation allowancd is made on expenditure incurred prior to Dec 96.

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Enclosure 2 of PWSC(97-98)45

COMPARISON OF THE APPROVED AND
REVISED PROJECT ESTIMATES

A comparison of the approved and revised project estimates is as follows -

2. As regards (a), the increase of $6.4 million is due to the increased number of slopes expected to be dealt with under the project.

3. As regards (b), the increase of $14.9 million is due to the increased number of slopes expected to be inspected under the project.

4. As regards (c), of the total increase of $1.8 million -

1. $0.4 million is for the provision of additional professional staff resources to study and review the computing requirement for an increased Catalogue size of 60 000 slopes; and

2. $1.4 million is for the provision of technical staff resources to carry out the additional data input for the increased Catalogue size of 60 000 slopes.

5.As regards (d), the increase of $0.4 million is to enhance hardware and software facilities to cater for the increased Catalogue size.

6.As regards (e), of the total increase of $1.2 million -

1. $1.1 million is to meet the increase in transport costs for site inspections by consultants for the estimated increase of 10 000 slopes; and

2. $0.1 million is for the provision of equipment and tools for the additional consultants to handle the estimated increase of 10 000 slopes.

7.As regards (f), the increase of $0.8 million is lower in proportion than the proposed increase of the approved project estimate as a whole in view of the greater certainty of the total number of slopes in the territory that need registration.

(KK219)

* We convert the approved project estimate (Dec 94) to approved project estimate (Dec 96) by using the 9%trend labour and construction index for the year 1995 and the 8% trend labour and construction index for the year 1996. No inflation allowancd is made on expenditure incurred prior to Dec 96.