For discussion
on 24 February 1999

PWSC(98-99)68

ITEM FOR PUBLIC WORKS SUBCOMMITTEE OF FINANCE COMMITTEE

HEAD 704	-	DRAINAGE
Civil Engineering	-	Drainage and erosion protection
92CD	-	Drainage improvements in Yuen Long, Kam Tin, Ngau Tam Mei and Tin Shui Wai, stage 1

Members are invited to recommend to Finance Committee -

1. the upgrading of part of 92CD, entitled "Yuen Long, Kam Tin, Ngau Tam Mei and Tin Shui Wai drainage improvement, stage 1 - consultants' fees and site investigations" to Category A at an estimated cost of $20.6 million in money-of-the-day prices; and

2. the retention of the remainder of 92CD in Category B.

PROBLEM

Many local areas in Yuen Long, Kam Tin, Ngau Tam Mei and Tin Shui Wai are susceptible to frequent flooding due to the inadequacies of the existing drainage system and natural stream courses in the areas.

PROPOSAL

2. The Director of Drainage Services (DDS), with the support of the Secretary for Works, proposes to upgrade part of 92CD to Category A at an estimated cost of $20.6 million in money-of-the-day (MOD) prices for engaging consultants to undertake site investigations, impact assessments and detailed design for the Yuen Long, Kam Tin, Ngau Tam Mei and Tin Shui Wai stage 1 drainage improvement works.

PROJECT SCOPE AND NATURE

3. The scope of 92CD comprises -

1. bank raising of about 2.5 kilometres of existing channel in Tin Shui Wai;

2. construction of about 7.5 kilometres of channel and ancillary works in Kam Tin and Ngau Tam Mei; and

3. construction of about 6.4 kilometres of drains in Yuen Long and Tin Shui Wai.

4. The part of the project we now propose to upgrade to Category A is for site investigations and design consultancy for the drainage improvement works as described in paragraph 3 above. The scope of the proposed consultancy includes -

1. site investigations and surveys;

2. impact assessments; and

3. detailed design, including preparation of tender documents and assessment of tenders.

5. The remainder of 92CD comprises construction of the drainage improvement works under stage 1.

JUSTIFICATION

6. Yuen Long, Kam Tin, Ngau Tam Mei and Tin Shui Wai are susceptible to frequent flooding during typhoons or heavy rainstorms. We built the existing drainage system in Yuen Long and Tin Shui Wai more than 20 years ago with its capacity designed to meet the flow requirements and flood protection standards at that time, which were one in 10 years return period for rural areas and one in 50 years return period for developed areas. However, the rapid urbanisation over the years has exacerbated the flooding problems in the areas. The extensive changes in land use and rapid development in the rural areas have also significantly overloaded the existing natural stream courses in Kam Tin and Ngau Tam Mei areas.

7. We commenced 52CD "Land drainage and flood control study phase II - consultants' fees and investigations" in 1991 to review the drainage systems in the North and North West New Territories. We completed the study in 1993 and the study recommended the implementation of a series of river training works to alleviate the flooding hazard in the North West New Territories, including the low-lying areas of Yuen Long and Kam Tin and the commissioning of drainage master plan studies. The former will improve the hydraulic capacity of main rivers while the latter will resolve the inadequacies of tributaries and local drainage system.

8. We planned to implement river training works for the Shan Pui River and Kam Tin River in phases starting at the downstream end. We commenced the improvement works at the river mouth in 1993 under 60CD "North West New Territories development - main drainage channels for Yuen Long and Kam Tin - stage 1 phase 1" for completion in 1999. We commenced the improvement works at part of the upper catchments in 1995 under 43CD "North West New Territories development - main drainage channels for Yuen Long and Kam Tin - stage 1 phase 2" for completion in 1999. We plan to commence the improvement works at the remaining part of the upper catchments under 81CD "North West New Territories development - main drainage channels for Yuen Long and Kam Tin - remainder" in mid-1999 for completion in early 2003. When the main drainage channels are in place, we can start the improvement works for the tributaries and local drainage system.

9. In 1996, we commissioned 83CD "Yuen Long, Kam Tin, Ngau Tam Mei and Tin Shui Wai drainage master plan study" to assess and recommend measures to resolve the inadequacies of tributaries and local drainage systems in the study areas. We completed the study in December 1998 and identified a series of improvement works to upgrade the existing stream courses and local drainage system in Yuen Long, Kam Tin, Ngau Tam Mei and Tin Shui Wai to the required flood protection standards of one in 50 years and to increase the capacity of the existing channel in Tin Shui Wai. The proposed improvement works will form an integral part of the overall flood control programme for the North West New Territories with a view to alleviating the flooding problems in the areas.

10. Owing to a lack of in-house staff resources, DDS proposes to employ consultants to carry out site investigations, impact assessments and detailed design works to facilitate the implementation of the proposed drainage improvement works under 92CD.

FINANCIAL IMPLICATIONS

11. We estimate the cost of the proposed consultancy to be $20.6 million in MOD prices (see paragraph 12 below), made up as follows -

		$ million
(a) Consultants' fees for		10.1
supervision of site investigations and surveys	0.6
traffic impact assessment	0.8
environmental impact assessment	1.2
detailed design including preparation of tender documents and assessment of tenders	7.5
(b) Site investigations and surveys		5.3
(c) Contingencies		1.5
		______
Sub-total		16.9	(at December 1997 prices)
(d) Provision for price adjustment		3.7
		______
Total		20.6	(in MOD prices)
		______

A breakdown by man months of the estimate for consultants' fees is at the Enclosure.

12. Subject to approval, we will phase the expenditure as follows –

13. We have derived the MOD estimates on the basis of the Government's latest forecast of trend labour and construction prices for the period 1999 to 2003. We will tender the proposed consultancy under a lump-sum contract. The consultants will in turn appoint contractors for the site investigation and survey works on a re-measurement basis through a competitive tendering process. The consultants will adopt this form of contract as they cannot determine in advance the exact extent of the site investigation and survey works required. We will allow for price adjustment in the consultancy agreement itself as the project duration will be more than 12 months.

14. The proposed consultancy will not give rise to any recurrent expenditure.

PUBLIC CONSULTATION

15. We presented the findings and recommendations of the study under 83CD "Yuen Long, Kam Tin, Ngau Tam Mei and Tin Shui Wai drainage master plan study" to Ha Tsuen Rural Committee on 4 August 1998, Ping Shan Rural Committee on 2 September 1998, Kam Tin Rural Committee on 10 September 1998, Pat Heung Rural Committee on 12 September 1998 and Yuen Long Provisional District Board on 24 September 1998. All supported the implementation of the entire project.

ENVIRONMENTAL IMPLICATIONS

16. The project contains a designated project under Schedule 2 of the Environmental Impact Assessment (EIA) Ordinance. An environmental permit is required for this project. We provided a project profile for the designated project to the Director of Environmental Protection (DEP) in July 1998. DEP issued an EIA study brief in September 1998. We will prepare an EIA report to cover this part of the project to meet the requirements under the EIA Ordinance. Regarding the non-designated project elements of the project, we will address the related environmental issues at the detailed design stage. The proposed consultancy itself will not have any adverse environmental implications.

LAND ACQUISITION

17. The consultancy does not require land acquisition.

BACKGROUND INFORMATION

18. We commissioned 83CD "Yuen Long, Kam Tin, Ngau Tam Mei and Tin Shui Wai drainage master plan study" in 1996 and completed the final study report in December 1998. The study has identified a series of drainage improvement works and recommended a two-staged implementation programme.

19. We upgraded 92CD "Drainage improvements in Yuen Long, Kam Tin, Ngau Tam Mei and Tin Shui Wai, stage 1", which is the stage 1 of the improvement programme, to Category B in September 1998. We plan to start the proposed design consultancy in July 1999 for completion in October 2002. We plan to start construction of the drainage improvement works in February 2002 for completion in September 2006.

20. The stage 2 works comprises improvement works for five streamcourses in rural or undeveloped areas in Kam Tin and Yuen Long. At present, these areas are not susceptible to flooding. However, we anticipate that with future development of the areas, flood protection measures will be required. We will carry out the necessary improvements under a separate project.

Works Bureau
February 1999

(PWSC0070/WIN3)

Enclosure to PWSC(98-99)68

Breakdown of estimates for consultants' fees -

Consultants' staff costs		Estimated man months	Average MPS* salary point	Multiplier factor	Estimated fee ($ million)
(a) Supervision of site investigations and surveys	Professional Technical	2 6	40 16	2.4 2.4	0.28 0.29
(b) Traffic impact assessment	Professional Technical	3 7	40 16	2.4 2.4	0.43 0.33
(c) Environmental impact assessment	Professional Technical	5 10	40 16	2.4 2.4	0.71 0.48
(d) Detailed design including preparation of tender documents and assessment of tenders	Professional Technical	30 70	40 16	2.4 2.4	4.26 3.34
_____
Total consultants' staff costs					10.1
_____
Out-of-pocket expenses
Site investigations and surveys	Total out-of-pocket expenses				5.3
_____

Notes

1. A multiplier factor of 2.4 is applied to the average Master Pay Scale (MPS) point to arrive at the full staff costs including the consultants' overheads and profit, as the staff will be employed in the consultants' offices. (At 1.4.1997, MPS pt. 40 = $59,210 per month and MPS pt. 16 = $19,860 per month)

2. Out-of-pocket expenses are the actual costs incurred. The consultants are not entitled to any additional payment for overheads or profit in respect of these items.

3. The figures given above are based on estimates prepared by the Director of Drainage Services. We will only know the actual man months and actual fees when we have selected the consultants through the usual competitive lump sum fee bid system.

(PWSC0070/WIN3)