Summary of the planning standards and guidelines for overhead power lines



I. Guidelines on Provision

  1. The location of new pylons and overhead power lines should not dictate the pattern of future land use or sterilise land which has a good development potential.
  2. They should not be erected in existing urbanised areas, areas having substantial development potential, and district / local open space. Environmentally sensitive areas such as sites of special scientific interest, conservation area and country park should also be avoided as far as practicable.

II. Environment Considerations

  1. Their location and design should minimise the visual and ecological impacts on the landscape.
  2. They should be routed to avoid environmentally sensitive areas and ridge lines where practicable.
  3. In planning pylons, damage to the existing vegetation should be minimised and reinstatement landscape treatment should be provided where necessary.
  4. In environmentally sensitive areas such as country parks, the use of overhead pylons should be avoided as far as possible.
  5. Where permanent overhead lines in environmentally sensitive areas covered by paragraph (d) cannot be avoided, the Director of Agriculture and Fisheries (where development is within Country Park) should be consulted. The Director of Environmental Protection should be consulted to determine the appropriate level of environmental impact assessment to be undertaken.

III. Safety Considerations

The respective minimum safety clearances for conductors of various voltage levels are as follows :

  1. Minimum safety clearance for electricity safety consideration

    Voltage Level (kV)

    Minimum Safety Clearance (m)

    400

    5.5

    132

    3.7

    66

    3.2

    33

    2.9

    11

    2.9

  2. Minimum vertical ground clearance for electrical safety consideration

    Voltage Level (kV)

    Minimum Vertical Ground Clearance (m)

    400

    7.6

    132

    6.7

    66

    6.1

    33

    6.1

    11

    6.1

IV. Health Considerations

When permanent overhead power lines are planned, the following criteria, which are based on the International Radiation Protection Association Guidelines, should be met :

  1. The electric field strength should not exceed 5kV per metre (r.m.s.); and
  2. The magnetic flux density should not exceed 0.1 milli-tesla (r.m.s.).

These criteria are applicable to open areas where members of the public are expected to spend a substantial part of a day. The safety clearance and vertical ground clearance stipulated in the HKPSG have taken these criteria into account.

V. Preferred Working Corridor of Overhead Power Lines

  1. Preferred working corridor for 400kV and 132 kV overhead power lines supported on pylons

    Voltage Level (kV)

    Width of the Preferred Working Corridor (m)

    400

    50

    132

    36

  2. Preferred working circle and working corridor for conductors supported on poles

    Voltage Level (kV)

    Width of the Preferred Working Circle to Facilitate Pole Erection

    Width of the Preferred Corridor (m)

    132

    36

    21.4

    66

    24

    13

    33

    24

    12

    11

    24

    10


Last Updated on 18 August 1998