Environmental Impact Assessment Ordinance

Technical Memorandum

Annex 18


1. General

1.1. Landscape and visual impact assessment shall be directed towards the predicting and judging the significance of the effects that new development may have on landscape character and visual amenity. This annex describes the general approach and methodology for assessment of landscape and visual impacts. The methodology may vary from case to case, depending on the nature of the issues. However, it must be admitted that such an assessment involves subjective judgement and preference. The perception and aspiration of the community on particular landscape features must be taken into account.

2. Study Process

2.1 A landscape and visual impact assessment shall cover the following:

  1. defining the scope and contents of the study;

  2. a baseline study to provide for a comprehensive and accurate description of the baseline landscape and visual character;

  3. a review of the relevant planning and development control framework;

  4. impact studies to identify the potential landscape and visual impacts and predict their magnitude and potential significance; and

  5. recommendations on mitigation measures and implementation programme.

3. Scope and Contents

3.1 In setting the scope of the study, the following aspects shall be considered:

  • limits of the study area;

  • stages in the project life-cycle;

  • key issues to be addressed;

  • level of details required for baseline studies;

  • principal viewpoints to be covered;

  • system to be used for judging impact significance;

  • alternatives;

  • other development if cumulative impacts are to be assessed.

    4. Baseline Study

    4.1 The baseline study shall at least cover the following aspects:

    1. physical aspects such as geology, landform, drainage, soil, climate, including micro-climate;

    2. human aspects such as cultural features, landscape history, buildings and settlements, people affected and their perception of the landscape character; and

    3. aesthetic aspects such as the views available, visual amenity and visual character.

    4.2 The baseline study shall present an appraisal of the landscape and visual resource of the study area. It shall focus particularly on the sensitivity of the landscape and visual system and its ability to accommodate change.

    5. Review of the Planning and Development Control Framework

    5.1 Plans or planning studies such as development statements, outline development plans, outline zoning plans, layout plans or planning briefs, and lease conditions may contain guidelines and control on urban design concept, building height profile, designated view corridors; specific design elements including areas of high landscape value, coastal protection areas, landmarks and monuments, special design areas and open space network; and other design specifications that may affect the architectural form of the project. A review of these documents shall provide an insight to the future outlook of the area affected and the ways the project can fit into the wider environment.

    6. Landscape Impact Assessment Study

    6.1 Landscape impact assessment shall assess :

    • direct impacts upon specific landscape elements;

    • more subtle effects upon the overall pattern of landscape elements that give rise to landscape character, and local and regional distinctiveness;

    • impacts upon acknowledged special interests or values such as areas of high landform with special landscape significance.

    6.2 Examples of special landscape features which may contribute to the landscape character of a site, an area or a region include:

    • areas of distinctive landscape character
    • e.g. the "genius loci" or characteristics patterns and combinations of landform and land coverage creating a sense of place;
    • valued landscape
    • e.g. country parks, protected coastline, areas of high landscape value, woodland, scenic spots;
    • other conservation interest
    • e.g. Nature Reserves, SSSIs, designed buffer zones, wetlands, historic landscapes, sites or buildings of culture heritage;
    • specific landscape elements
    • e.g. hilltops, ridgeline, coastline, river valleys, woodlands, ponds.

    7. Visual Impact Assessment Study

    7.1 Visual impact assessment shall identify and predict the type and extent of visual impacts relating to:

    • visual compatibility with surroundings
    • e.g. massing, height, shape, proportion and rhythms of building elements, colour and material used;
    • visual obstruction
    • e.g. blocking of views towards existing landscape features; or existing/planned view corridors towards landmarks and notable features;
    • improvement of visual quality
    • e.g. clearance of visual obstruction and blight, appealing design features that enhance attractiveness of the landscape; and
    • glare from direct or reflected sunlight or man-made light source
    • e.g. uncomfortable eye feeling caused by light interference from structures faced with mirror or polished materials or from direct light sources generated from the proposed development.

    7.2 In assessing visual impacts, it is important to cover all possible viewpoints. If this is not practicable, key viewpoints shall be selected on major routes e.g. roads, walkways, footpaths and hiking tracks; and at activity nodes e.g. residential areas, important public open spaces and landmarks etc. The location of these viewpoints shall be typical.

    7.3 When considering views from a main route, it will be more effective to have a sequence of views recording the changing visual events along the route.

    8. Mitigation Measures

    8.1 Mitigation is not only concerned with damage reduction but shall include consideration of potential landscape visual enhancement. Wherever possible design that would enhance the landscape and visual quality shall be adopted.

    8.2 Alternative design that would avoid or reduce the identified impacts on landscape, or that would make the project visually compatible with the setting shall be thoroughly examined before adopting other mitigation or compensatory measures to alleviate the impacts.

    8.3 Possible measures that may mitigate or compensate the impacts include:

    • remedial
    • e.g. screen painting, facade treatment, colour scheme and texture of materials used; and
    • compensatory
    • e.g. landscape treatment, compensatory planting, creation of interesting landscape or visual features.

    8.4 A practical programme and funding proposal for the implementation of the recommended mitigation measures shall be worked out. These shall be integrated with the overall development programme and costing of the whole project.

    9. Presentation Methods

    9.1 To illustrate the landscape and visual impacts of a project, as well as effects of the mitigation measures, choice of appropriate presentation methods is important. These methods include perspective drawings, plans and section/elevation diagrams, photographs on scaled physical models, photo-retouching and photomontage. These methods shall be used extensively to facilitate communication among the concerned parties.

    9.2 The technical details of preparing the illustrations shall be recorded. To facilitate verification of the accuracy, the Authority will reserve the right to examine the full details.