For discussion PWSC(97-98)26
on 21 May 1997


Transport - Roads
644TH - Highways between Shap Pat Heung iInterchange and Pok Oi iInterchange - Pok Oi fFlyover

    Members are invited to recommend to Finance Committee the upgrading ofto upgrade 644TH to Category A at an estimated cost of $175.438 million in money-of-the-day (MOD) prices for the construction of the Pok Oi fFlyover.


We expect traffic will overload the existing Pok Oi iInterchange (POI) after the opening of the Country Park Section (CPS) of Route 3 in August 1998. This will frustrate many housing developments in the North West New Territories (NWNT).


2. The Director of Highways (DHy), wWith the support of the Secretary for Transport and the Secretary for Housing, the Director of Highway proposes to upgrade 644TH to Category A at an estimated cost of $175.438 million in money-of-the-day (MOD)MOD prices for the construction of a new flyover acrossabove the existing POI.


3. The scope of the project comprises -

  1. construction of a dual two-lane trunk road about 400 metres in length which includes a 154 metres long flyover acrossabove the existing roundabout at the POI;

  2. construction of two single two-lane slip roads each about 200 metres in length connecting the above trunk road and the existing district distributor roads of Yuen Long Highway;

  3. resurfacing of part of the existing district distributor roads of Yuen Long Highways; and

  4. ancillary drainage, pavement, street lighting, traffic aids, noise barriers, landscaping and slope embankment works.


4. The population at NWNT has increased substantially in recent years due to theto completion of a number of large housing developments in the area. The Commissioner for Transport completed a survey in October 1996 and found that traffic using POI hads almost reached its handling capacity during morning peak hours. After the commissioning of Route 3 CPS in August 1998, all traffic between Route 3 CPS and Yuen Long/Tuen Mun will have to pass through POI. As a result, we estimate that the traffic volume at POI would exceed the capacity of the interchange by 65% by 1999.

5. The proposed Pok Oi fFlyover will form part of the highway between Shap Pat Heung iInterchange and POI. It will provide a route for a route for through traffic between the Route 3 CPS in the north and the Yuen Long Highway in the south to relieve the existing POI. On completion of the proposed flyover in 1999, we estimate that the traffic using POI will have a reserve capacity of 25%be reduced to 75% of its capacity.

6. As the site of the proposed works lies partly within the works site of the Route 3 CPS project, we intend to entrust the detailed design, construction and supervision of the proposed works to the franchisee of the Route 3 CPS project to enable early completion of the improvement works and to eliminate interface problems.


7. We estimate the capital cost of the proposed works to be $175.438 million in MOD prices (see paragraph 9 below), made up as follows -

$ million
(Dec 1996)

(a) Bridge structure


(b) Roadworks, and ancillary works


(c) Noise mitigation measures


(d) Consultants’ fees for design and construction stages


(ef) Site staff costs


(fg) Contingencies




(at December
1996 prices)

(h) Inflation allowance




8. Subject to agreement with the franchisee of Route 3 CPS franchisee, the Government will reimburse the franchisee the actual cost in line with the progress upon completion of the works, subject to a ceiling of $175.438 million.

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


$ million
(Dec 1996)


$ million

1997 - 98




1998 - 99




1999 - 00






10. We have derivedderive the MOD estimate on the basis of the Government's forecast of trend labour and construction prices forover the period between 1997 toand 2000.

11. We estimate the additional annually recurrent expenditure to be $1.292.24 million.


12. We consulted the Yuen Long District Board on the proposed works on 19 December 1996 and 7 January 1997. Members supported the scheme and urged for its early implementation.

13. We gazetted the proposed works of 644TH under the Roads (Works, Use and Compensation) Ordinance on 14 February 1997 and received no objections.


We completed an environmental impact assessment (EIA) covering construction and operation of the Pok Oi Flyover in Apri1 1997. The EIA study concluded that there would be no adverse air quality impact due to the effect of traffic but recommended the provision of noise reducing surfacing and noise barriers to reduce the traffic noise levels at nearby sensitive receivers. We will also provide landscape works to ameliorate the visual impact along the road. As to the short term environmental impacts, we will control noise, dust and site run-off during construction through the implementation of mitigation measures in the works contract. The proposed mitigation measures will form part of the entrustment to the Route 3 (CPS) Co. Ltd.

14. The consultants of DHy completed an Environmental Impact Assessment (EIA) in April 1997 to assess the environmental impacts arising from the construction and operation of the project. The EIA Sub-committee of the Advisory Council on the Environment considered the EIA findings on 5 May 1997 and recommended endorsement of the EIA Final Report.

15. The study concluded that there would be no adverse air quality impact on nearby sensitive receivers. We shall implement the following noise mitigation measures to reduce the traffic noise impact to within the established guidelines -

  1. construction of 302m and 310m long 2.7m high noise barriers (on top of the 0.8m high parapet) on the eastern and western side of the flyover respectively;

  2. provision of absorptive material to the noise barriers and low noise surfacing material to the new road; and

  3. provision of sections of temporary noise barriers of 0.8 - 3.5m high along the temporary slip roads and existing Yuen Long Highway.

16. For short term construction impacts, we shall control dust, noise and site run-off nuisance to within established guideline/standards through the implementation of mitigation measures in relevant contracts. We shall implement the environmental monitoring and auditing programme recommended in the EIA study.


17. The proposed works do not require any land acquisitionresumption and clearance.


18. We upgraded 644TH to Category B in February 1997. Subject to Finance Committee’s approval of the proposed project,Because of the extremely tight programme, the franchisee of the CPS Route 3 CPS franchisee will has scheduled to start the works in July 1997 for completion in December 1998.


Last Updated on 16 August 1999