PWSC(1999-2000)39

For discussion
on 2 June 1999

ITEM FOR PUBLIC WORKS SUBCOMMITTEE
OF FINANCE COMMITTEE

HEAD 704 - DRAINAGE
Environmental Protection - Sewerage and sewage treatment
312DS - Strategic Sewage Disposal Scheme Stage I:construction supervision of the main works
    Members are invited to recommend to Finance Committee an increase in the approved project estimate of 312DS from $118.2 million by $98.8 million to $217.0 million in money-of-the-day prices.

PROBLEM

The approved project estimate (APE) of 312DS is insufficient to cover the costs of construction supervision of the main works of the Strategic Sewage Disposal Scheme (SSDS) Stage I.

PROPOSAL

2. The Director of Drainage Services (DDS), with the support of the Secretary for Planning, Environment and Lands, proposes to increase the APE of 312DS from $118.2 million by $98.8 million to $217.0 million in money-of-the-day (MOD) prices. The proposed increase of $98.8 million represents an increase of about 16% over the original estimated cost of $610.0 million for construction supervision of the main works of the SSDS Stage I.

PROJECT SCOPE AND NATURE

3. 312DS covers the expenditure on the construction supervision of 12 project items created under the Capital Works Reserve Fund (CWRF) for the outstanding main works of the SSDS Stage I (except the eastern tunnels) after the closure of the Sewage Services Trading Fund (SSTF) on 31 March 1998. These items and their respective APEs are listed at Enclosure 1.

JUSTIFICATIONS

4. The construction supervision of the main works of SSDS Stage I was originally funded by the SSTF under 018SS with an APE of $610.0 million in MOD prices. As preparation was made to wind up the SSTF, we estimated that up to 31 March 1998, $491.8 million would have been spent. On the basis of this estimate, Finance Committee on 27 February 1998 approved the inclusion of 312DS in Category A under the CWRF with an APE of $118.2 1 million in MOD prices to fund the costs of the construction supervision of the outstanding main works of SSDS Stage I, with the exception of the supervision of two contracts for the four eastern tunnels, which is covered by project item 286DS.

5. DDS prepared the current project estimate of 312DS in late 1997 based on the forecast completion dates of the works available at that time. These indicated that the main works covered by the project item would be completed by August 1999. This was before the problems with the mucking system left by the first contractor and the extent of poor ground conditions in the Tsing Yi to Stonecutters tunnel route were known. We now envisage that the whole of the main works covered by 312DS will be substantially completed in November 2000. It is therefore necessary to retain some resident site staff to supervise the works over the longer construction period. In addition, the consultants’ fee for the construction stage of the contracts will be increased as a result of the extended period of supervision of the contracts.

6. The main reasons for the extensions and delays in completion of the works involved are –

  1. the completion works for the two western tunnels has been delayed by the need to replace the faulty mucking system left behind by the default contractor and by poor ground conditions;

  2. the forfeiture of the two tunnel contracts in December 1996 has caused knock-on disruptions on the completion and commissioning of other main works contracts. The completion dates for six contracts need to be extended to various degrees. The details of the impacts on each of the contracts are summarized at Enclosure 2; and

  3. the completion of the works related to SSDS Stage I chemical dosing facilities, including works essential for the testing and commissioning of the facilities, has been delayed due to the poor performance of the contractor.

The original and revised completion dates of the works are listed at Enclosure 2 with brief reasons for the extensions and delays.

7. Following a review of the financial position of 312DS and the construction supervision necessary for the completion of the main works, we consider it necessary to increase the APE from $118.2 million by $98.8 million to $217.0 million in MOD prices (see paragraph 10 below) to cover the total cost of the construction supervision under the project item. A summary breakdown of the proposed increase of $98.8 million is as follows:-

FactorAmount of
Increase/
(Decrease)
($ million)
Amount of
Increase/
(Decrease)
in MOD prices
($ million)
%
Increase/
(Decrease)
(a) consultants' fees for construction supervision in relation to: 12.012.012.1
  1. delay in completion of the western tunnels
3.1
  1. knock-on disruptions to six contracts due to for feiture of original tunnel contracts
7.6
  1. poor performance of the contractor for the chemical dosing facilities
(b) resident site staff costs in relation to: 99.0100.2
  1. delay in completion of the western tunnels
24.5
  1. knock-on disruptions to six contracts due to forfeiture of original tunnel contracts
64.4
  1. poor performance of the contractor for the chemical dosing facilities
10.1
(c)contingencies(12.2)
_______
(12.3)
_______
Total98.8
_______
100.0
_______

The contingencies amount allowed in the original project estimate has been reviewed and reduced in view of the higher degree of estimation certainty at the current stage. The proposed net increase of $98.8 million in MOD prices represents an increase of about 16% over the original APE of $610.0 million under 018SS. A comparison of the cost breakdowns of the APE and the revised project estimate for 312DS, together with the breakdown of the additional costs attributable to the extensions and delays explained in paragraph 6 above, is at Enclosure 3 for reference. In addition, a breakdown of the estimates for consultants’ fees is also at Enclosure 4.

8. Up to end March 1999, the total expenditure on the SSDS Stage I was $5.4 billion, of which $4.4 billion was spent under the SSTF before its closure. At the time the related SSTF projects were transferred to CWRF, we forecast that We estimate that the whole SSDS Stage I, comprising 19 project items including 312DS, would be completed within anthe original overall estimate of $8.2 billion. According to current forecasts, if the proposed increase in the APE for 312DS is approved, the overall estimate of $8.2 billion for the completion of SSDS Stage I by late 2000 will not be exceeded. Offsetting savings of up to $135.22 million can be identified from the unspent contingencies of other items. Details of the forecast are shown at Enclosure 5. The final costs of these seven projects have now become more certain as the works involved are nearing completion. While the project estimate for 312DS will need to be increased, we anticipate corresponding reductions in the final costs of other related projects under the SSDS Stage I programme. Details of these anticipated savings are listed at Enclosure 5.

9. The establishment of resident site staff has been kept under close review to ensure that staffing levels are commensurate with workload. Whenever a substantial part of the construction works is completed, the strength of the resident site staff is reduced and different teams are combined to achieve best utilization of staff resources. The details of the resident site staffing level for the main works of the SSDS Stage I in the previous 18 months and coming years until completion are listed at Enclosure 6.

FINANCIAL IMPLICATIONS

10. Subject to approval, we will phase the expenditure as follows -

Year$ million
(Dec 1998)
Price
adjustment
factor
$ million
(MOD)
Up to 31 March 1999 89.8 21.0000089.8
1999 - 2000 69.41.02625 71.2
2000 - 2001 34.81.0621737.0
2001-200217.3
______
1.0993419.0
______
211.3
______
217.0
______

11. 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 2002.

12. The proposed increase in the APE will not give rise to additional recurrent expenditure.

PUBLIC CONSULTATION

13. We consulted the public on SSDS Stage I before the commencement of works in 1994. We briefed the Legislative Council Panel on Environmental Affairs (EA Panel) and Planning, Lands and Works (PLW Panel) on the progress of the Stage I works on 5 February and 4 May 1999. Also, we have provided quarterly progress reports on Stage I tunnelling works to the Advisory Council on the Environment since January 1999. We consulted the EA Panel and the PLW Panel on the proposed increase in the APE for this project item on 4 May 1999. Members were content that the proposal to increase the APE for 312DS be put to PWSC.

ENVIRONMENTAL IMPLICATIONS

14. The proposed increase in the APE does not have any adverse environmental implications. At the PWSC meeting held on 26 May 1999, Members requested additional information on the environmental impact that has occurred because of the delays in connecting the tunnels to the Stonecutters Island Sewage Treatment Works. This is set out in Enclosure 7.

LAND ACQUISITION

15. The project item does not require land acquisition.

BACKGROUND INFORMATION

16. The SSDS Stage I works comprise upgrading of existing preliminary treatment works; construction of a series of deep sewage collection tunnels to collect sewage from the urban Kowloon and north east Hong Kong Island; and building a new centralized sewage treatment works at Stonecutters Island to treat the sewage. The treated effluent is to be discharged via an interim outfall to the more open waters west of Victoria Harbour.

17. In view of the size and complexity of the civil, electrical and mechanical works involved, the SSDS Stage I was implemented under 15 construction contracts comprising four advance works contracts and 11 main works contracts. These contracts commenced in stages in 1994 and 1995 respectively.

18. The construction of the sewage tunnel transfer system was included in two of the 11 main works contracts. Owing to the unilateral suspension of works in all six sewage tunnels by the first contractor, the two tunnel contracts were forfeited in December 1996. Subsequently, the tunnel completion works were re-let in three separate contracts (two tunnels in each contract) in July 1997 and January 1998. Among these tunnel completion contracts, 018SS covers the construction supervision of the tunnel completion contract for the western tunnels funded under 320DS. The construction supervision of the other two tunnel completion contracts is funded under 286DS.

19. The Finance Committee approved the creation and direct inclusion of 312DS in Category A on 27 February 1998 to cover the outstanding commitments and obligations under 018SS upon the closure of the SSTF on 31 March 1998.

20. As part of the additional construction supervision cost arises from the forfeiture of the two tunnel contracts, we intended to pursue a claim for losses arising from re-entry of the two tunnel contracts through arbitration. We will ascertain these losses after completion of the tunnelling works.

21. We previously submitted the funding proposal for 312DS to Members on 26 May 1999 3. At the meeting, Members requested the additional information as follows: (a) details of anticipated savings arising from other projects under the SSDS Stage I programme; (b) in quantitative terms, the environmental impact that has occurred because of the delays in connecting the tunnels to the Stonecutters Island Sewage Treatment Works; and (c) whether the two partners of joint venture tunneling contractor would be suspended from tendering public works contracts as a result of their performance under the contracts for the SSDS Stage I sewage collection tunnels which had to be re-entered. The Administration withdrew the paper in light of the comments made by Members. We have now set out the additional information for (a) and (b) in Enclosure 5 and 7 respectively. Information on (c) has been circulated to Members in a separate Information Note PWSCI(1999-2000)4.

--------------------------------------------

Planning, Environment and Lands Bureau
Works Bureau
May 1999

(PWSC01312/WIN5)

Enclosure 1 to PWSC(1999-2000)39

312DS - Strategic Sewage Disposal Scheme Stage I:
construction supervision of the main works

A list of outstanding SSDS Stage I works of which the construction supervision are covered by 312DS is as follows -

Item No.TitleExpenditure
up to 31.3.98
under SSTF
($ million)
Approved
Project
Estimate
under CWRF
($ million)
288DSSSDS Stage I: chemical dosing facilities 104.139.2
304DSSSDS Stage I: sewer tunnel system from Chai Wan and Tseung Kwan O to Kwun Tong306.136.3
305DSSSDS Stage I: SCISTW* sludge treatment facilities231.343.7
306DSSSDS Stage I: SCISTW* - sedimentation tanks (civil works) 347.624.5
307DSSSDS Stage I: pumping stations electrical and mechanical equipment223.1214.3
308DSSSDS Stage I: SCISTW* - pumping stations, buildings and site development299.897.3
309DSSSDS Stage I: upgrading existing preliminary treatment works607.6234.1
310DSSSDS Stage I: sedimentation tanks electrical and mechanical equipment276.4125.1
311DSSSDS Stage I: sewer tunnel system from Kwun Tong and Kwai Chung to Stonecutters Island389.739.4
315DSSSDS Stage I outfall 445.1117.6
316DSSSDS stage I: construction of sludge transfer facilities and supply of sludge containers28.823.7
320DSSSDS stage I: completion of sewer tunnel system from Kwai Chung to Stonecutters Island51.5
______
487.6
______
Total3,311.1
_____
1,482.8
______

* SCISTW = Stonecutters Island Sewage Treatment Works

Notes :

(1) SCISTW denotes Stonecutters Island Sewage Treatment Works.

(21) 304DS and 311DS are project items covering the works under the original tunnel contracts. After their forfeiture in December 1996, these project items provide funds for the tunnel maintenance contract for maintaining the unfinished tunnels and taking security of all the tunnel sites before commencement of the completion works. With the completion of the tunnel maintenance contract in January 1998, the works under these project items are substantially completed.

(32) The construction supervision of the completion of the four eastern tunnels is funded by 286DS entitled "SSDS stage I: completion of sewage tunnel system from Chai Wan and Tseung Kwan O to Kwun Tong and from Kwun Tong to Stonecutters Island".

Enclosure 2 to PWSC(1999-2000)39

312DS -Strategic Sewage Disposal Scheme Stage I:
construction supervision of the main works

Forecast completion dates of projects which construction supervision are covered by 312DS -

Item No.TitleCompletion
Date
Anticipated
in the Last
PWSC
Submission
Actual
Completion
Date/Latest
Forecast
Completion
Date
Brief Reasons
For Delay & Extension
288DS SSDS Stage I: chemical dosing facilities Jan 1998 Jan 1999 Owing to financial problems, the contractor has difficulties in mobilizing sufficient resources to complete the works as scheduled. The persistent poor performance of the contractor caused significant delay to the completion of the contract.
304DS SSDS Stage I: sewer tunnel system from Chai Wan and Tseung Kwan O to Kwun TongJul 2000Tunnel maintenance work substantially completed in January 1998 (see note (1) Enclosure 1).
305DSSSDS Stage I: SCISTW sludge treatment facilitiesOct 1997Sep 1997306DSSSDS Stage I: SCISTW -sedimentation tanks (civil works)Jun 1997Jun 1997
307DSSSDS Stage I: pumping stations electrical and mechanical equipmentMay 1998Jun 1999As the result of the delay in completion of tunnel transfer system, significant portion of the sewage from SSDS Stage I catchment cannot be made available for testing and commissioning of the pumping facilities as originally planned. Alternative arrangements have to be worked out and agreed with the contractor hence causing delays to the completion of the contract.
308DSSSDS Stage I: SCISTW -pumping stations, building and site developmentMar 1998Mar 1999The delay in completion of the E & M works at SCISTW caused knock-on delays in handing over the associated works areas for the completion of outstanding works under the contract hence causing delay to its completion.
309DSSSDS Stage I: upgrading existing preliminary treatment worksApr 1998Mar 1999The forfeiture of the tunnel contracts disrupted the interfacing works for diverting the Preliminary Treatment Works flows to the tunnel transfer system. As a result, the scope of works under the contract has to be revised and some of the facilities have to be amended to cope with the changes hence causing delays to the completion of the contract.
310DSSSDS Stage I: sedimentation tanks electrical and mechanical equipmentApr 1998May 1999 As the result of the delay in completion of the tunnel transfer system, significant portion of the sewage from SSDS Stage I catchment areas cannot be conveyed to SCISTW for testing and commissioning of the sedimentation facilities. Alternative arrangements have to be worked out and agreed with the contractor hence causing delays to the completion of the contract.
311DSSSDS Stage I: sewer tunnel system from Kwun Tong and Kwai Chung to Stonecutters IslandJul 2000Tunnel maintenance work substantially completed in January 1998 (see note (1) of Enclosure 1).
315DSSSDS Stage I outfall May 1998Nov 2000As the result of the delay in completion of the tunnel transfer system, significant portion of the sewage flow from SSDS Stage I catchment areas cannot be conveyed to SCISTW for treatment and subsequent discharge via the outfall. The effluent produced from the treatment of North West Kowloon sewage is not adequate for commissioning of the outfall and hence the contract is extended to provide an alternative operational arrangement until the availability of the tunnel flow.
316DSSSDS Stage I: construction of sludge transfer facilities and supply of sludge containersMay 1999May 2000The interim sludge disposal service under the contract is extended to cope with the latest forecast completion date of the tunnel transfer system.320DSSSDS Stage I: completion of sewer tunnel system from Kwai Chung to Stonecutters IslandAug 1999Nov 2000Replacement of mucking system and poor ground conditions cause delay in completion of the contract.

* SCISTW = Stonecutters Island Sewage Treatment Works.

(PWSC0131/WIN5)

Enclosure 3 to PWSC(1999-2000)39

312DS -Strategic Sewage Disposal Scheme Stage I:
construction supervision of the main works

A comparison of the cost breakdowns of the approved project estimate and the revised project estimate -

Approved
Project
Estimate
($ million)
Revised
Project
Estimate
($ million)
Increase
(Decrease)
($ million)
(a) consultants' fees for construction supervision 25.037.012.0
(b) resident site staff costs 62.0161.099.0
(c) contingencies31.219.0(12.2)
__________________
Total118.2217.098.8
__________________

2. The breakdown of the increase in costs of construction supervision and resident site staff with respect to the causes of extensions and delays detailed in paragraphs 6 and 7 of the paper is shown as follows -

Amount of Increase/
(Decrease)
$ million
(a) Delay in completion of the western tunnels under 320DS 27.6
(b) Knock-on disruptions to six contracts due to forfeiture of original tunnel contracts72.0
(c) Poor performance of the contractor for 288DS11.4
______
Sub-total111.0
(d) Reduction in contingencies(12.2)
______
Total98.8
______

(PWSC0131/WIN5)

Enclosure 4 to PWSC(1999-2000)39

312DS - Strategic Sewage Disposal Scheme Stage I:
construction supervision of the main works

Breakdown of estimates for consultants' fees

Consultants' staff costsEstimated
man
months
Average
MPS
salary
point
Multiplier
factor
Estimated
fee at
Dec 98
prices
($ million)
Estimated
fee in
MOD prices
($ million)
(a) Original Estimate
Construction
Supervision
Professional
Technical
149
50
40
16
2.4
2.4
22.5
2.5
22.5
2.5
Resident Site StaffProfessional
Technical
344
705
40
16
1.7
1.7
36.7
25.2
_____
36.8
25.2
_____
Sub-total (a)86.9
_____
87.0
_____
(b) Additional Costs
Construction
Supervision
Professional
Technical
67
23
40
16
2.4
2.4
10.1
1.2
10.7
1.3
Resident Site StaffProfessional
Technical
534
1093
40
16
1.7
1.7
57.0
39.0
_____
58.7
40.3
_____
Sub-total (b)107.3
_____
111.0
_____
(c) Revised Estimate
Construction SupervisionProfessional
Technical
216
73
40
16
2.4
2.4
32.6
3.7
33.2
3.8
Resident Site Staff Professional
Technical
878
1799
40
16
1.7
1.7
93.7
64.2
_____
95.5
65.5
_____
Sub-total (a) + (b)194.2
_____
198.0
_____

Notes :

(1) A multiplier factor of 2.4 is applied to the average 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 1.4.98, MPS pt. 40 = $62,780 p.m. and MPS pt. 16 = $21,010 p.m.). A multiplier factor of 1.7 is applied in the case of site staff supplied by the consultants.

(2) 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 after the completion of the works.

Enclosure 5 to PWSC (1999-2000)39

Details of anticipated savings from other SSDS Stage I projects

We have identified reductions in the final costs of other SSDS Stage I projects in the seven items below.

Item No.TitleApproved
Project
Estimate
(Note)
($ million)
(a)
Estimated
Final
Cost
(MOD)
($ million)
(b)
Cost
Reduction
(MOD)
($ million)
(a)-(b)
287DSSSDS Stage I: principal collection and treatment system - advance works31.1024.536.57
288DSSSDS Stage I: chemical dosing facilities 39.20 28.67 10.53
304DS SSDS Stage I: sewer tunnel system from Chai Wan and Tseung Kwan O to Kwun Tong 36.30 1.92 34.38
305DS SSDS Stage I: SCISTW* sludge treatment facilities 43.7032.8610.84
306DS SSDS Stage I: SCISTW* - sedimentation tanks (civil works) 24.5017.936.57
309DS SSDS Stage I: upgrading existing preliminary treatment works234.10205.2528.85
311DSSSDS Stage I: sewer tunnel system from Kwun Tong and Kwai Chung to Stonecutters Island 39.401.9237.48
_______
Total Cost Reduction 135.22

* SCISTW = Stonecutters Island Sewage Treatment Works.

With the works under the above items nearing completion, their final costs have become more certain. The sum of the unused contingencies for these items is greater than the proposed increase in APE of 312DS.

Note: The APEs of the projects are the costs of the outstanding works and contractual commitments to be funded under the CWRF upon the closure of the SSTF on 31 March 1998.

312DS- Strategic Sewage Disposal Scheme Stage I :
construction supervision of the main works

Savings identified in other items are sufficient to offset the proposed increase of $98.8 million (MOD) in the APE for 312DS as shown below -

Enclosure 6 to PWSC(1999-2000)39

312DS -Strategic Sewage Disposal Scheme Stage I:
construction supervision of the main works

Detailed staffing level of resident site staff covered by 312DS

DateProfessionalTechnicalClericalTotal
1 Oct 19975711636209
1 Apr 1998437619138
1 Oct 199829551397
1 Apr 19992742978
1 Oct 19992230860
1 Apr 20001519438
1 Oct 2000913325
1 Apr 200146212
1 Oct 20012428
1 Apr 20020000

Note :

(1) The RSS expenditure before 1 April 1998 was covered by SSTF item no.
018SS.

Enclosure 7 to PWSC(1999-2000)39

312DS - Strategic Sewage Disposal Scheme Stage I:
construction supervision of the main works

Environmental Consequence of Delays

Below are two sets of figures setting out the environmental consequence of the delay in completing the project. The first are for the additional pollution load arising as a consequence of all the delays since the first letting of the contracts in early 1995. These flow from the default of the first contractor, the need by the completion contractors to replace equipment left by the first contractor and the difficult conditions encountered at certain parts of the tunneling work, putting expected completion back from the original target of mid 1997 to November 2000. The second set are for the additional pollution load arising from the delays experienced since the completion contracts were let, which have put back the expected completion date from August 1999 (for the western tunnel system) and April 2000 (for the eastern tunnel system) to November 2000.

A. Estimated Additional Pollution load arising from all delays

Biological Oxygen Demand (BOD) - 119,000 tonnes
Suspended Solids -160,000 tonnes

B. Estimated Additional Pollution load arising from delays to completion contract works.

BOD - 24,000 tonnes
Suspended Solids -32,000 tonnes

2. These estimates are based on the conservative assumption that the Stonecutter's treatment plant would have operated at its design level of removing 55% of BOD and 70% of suspended solids. In practice, the plant has been removing 72% of BOD and 84% of suspended solids from the sewage flow that we have been able to direct to it in advance of completion of the collection tunnels.

1.The approved project estimate of 312DS ($118.2 million) was established on the basis of our estimated cumulative expenditure under 018SS of $491.8 million up to 31 March 1998, leaving an outstanding commitment of $118.2 million to be funded from the CWRF.]

2.This is the actual expenditure up to 31 March 1999.

3.Paper PWSC(1999-2000)15.