1
1.1
•
INTRODUCTION
Purpose of the Annex
the Eastern Harbour
Crossing
1.1.1
of The Hong Kong Island end (EHC) tunnel is located at Quarry Bay where an interchange is provided to give interconnection with the existing Island Eastern Corridor (IEC). This interchange is situated on the newly formed Quarry Bay reclamation to the north and west of Taikoo Shing Estate.
1 .1.2
A preliminary study of the impact the EHC will have on noise and air pollution levels in the vicinity of the Quarry Bay Interchange has been undertaken. This Annex presents а summary of the findings of this study.
1.2
1.2.1
The Proposed Eastern Harbour Crossing.
The proposed Quarry
Quarry Bay Interchange and its relation with the IEC and surrounding existing development is shown in Figure No.
C1.
1.2.2
The road tunnel will have dual two lane carriageways. Slip roads, two for ingress and two for egress, will connect the tunnel to the IEC in the eastbound and westbound directions. The predicted maximum traffic flows are shown in Figure No. C2 which, in the mid 1990's, will occur at peak hours only but will be over a longer period by the turn of the century when the tunnel is expected to be operating at its maximum daily capacity.
1.2.3 The purpose of the Quarry Bay Interchange is to provide а means of transporting traffic between the tunnel and the IEC. Because of the variety of traffic origins and destinations and the substantial difference in levels between the tunnel and the IEC, a series of merging, diverging, climbing and descending manoeuvers are required. To minimise the noise impact such manoeuvers can create the interchange has been designed to a high standard to ensure, as far as possible, free flow of traffic into and out of the tunnel.
1.2.4 The existing developments susceptable to the impact of traffic noise will be the residential blocks in Taikoo Shing Estate and the Canossian College. Predicted noise levels at these developments have been assessed and the locations where predictions have been determined are indicated on Figure No. Cl.
1.2.5 The road tunnel of the EHC is required to be ventilated by the provision of a fresh air supply and the extraction of vitiated air. This is achieved by a system of intakes and exhausts such that fresh air is supplied at both the tunnel portal and ventilation building but with vitiated air expelled at the ventilation building only. In this way air is expelled from the tunnel as far from existing development as possible. (See Figure No. C1).
1.2.6
Traffic on the IEC and the approaches to the tunnel will also be a source of air pollution. The effects of both this and the expelled air at the ventilation building have been considered in the study. Predictions of air pollution levels have been determined at locations adjacent to existing developments as indicated on Figure Cl.
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