LAND, PUBLIC WORKS AND UTILITIES
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Cadastral surveying is an important function of the office, serving the public and government by defining property boundaries. The office maintains a comprehensive graphical record of all leasehold and government land boundaries in the territory. Landowners may apply to re-establish private lot boundaries for redevelopment purposes for a fee. Legislation was introduced in 1991 to limit boundary surveys to authorised persons in order to protect the public, strengthen private sector practices and improve the cadastral survey system. Contracting out of some cadastral surveys covering small house lots in the New Territories continued in 1991.
The wide range of mapping coverage maintained by the office has always provided an important support service in the administration, planning and development of Hong Kong. The most definitive series of maps and the foundation of all other mapping is the large scale (1:1 000) basic topographical series (3 000 sheets). Smaller scale coverage starts at 1:5 000 (160 sheets) followed by coloured maps at scales 1:20 000 (16 sheets), 1:50 000 (two sheets), and down to single sheet coverage of 1:100 000 and 1:200 000. Two monochrome street map series at 1:10 000 and 1:15 000 of the urban areas in Hong Kong, Kowloon and parts of the New Territories are produced for special uses and as a base for the popular guide-book Hong Kong Guide – Streets and Places. Demand for leisure maps, in the form of the Countryside Series (six sheets) and the Tourist Guide, has been strong and the design and contents are continually under review to make subsequent editions more attractive and informative to users.
Maps are obtainable from conveniently located outlets throughout the territory.
The Survey and Mapping Office provides extensive cartographic and reprographic services for other government departments. These include full-colour mapping for the geological series, base maps for weather forecasting, aeronautical charts, electoral boundary maps, pollution control plans and photo-reproduction and plan copying of all types by the Reprographic Unit. The unit also provides essential back-up for in-house map production and other cartographic activities.
The computerised land information system installed in the Survey and Mapping Office in 1989 has started producing mapping and information products. The Kowloon District Survey Office is the first district which has its large-scale maps in digital form with land information processed and plans produced by sophisticated computer equipment. Up-to- date mapping information is readily available to map users. Besides producing standard survey sheets at scale 1:1 000 containing full topographical features, the system can also produce plans according to the user's specifications including features to be shown, such as buildings, roads, contour lines; colours and symbols for different features; plan scale and plan size. Mapping information in digital form may also be supplied to users on magnetic media, and direct on-line access to the central mapping database is possible. Data conversion for the other districts in the territory continues and is scheduled to be completed by 1993.
The Photogrammetric Survey Section provides aerial photographs and photogrammetric mapping as well as data and information for engineering design work, volumetric calculations for quarry and controlled tipping operations, environmental studies and town planning work. The Air Survey Unit is also on call for quick response photography in emergency operations such as storms, flooding and landslips.
A consultancy study on the survey and mapping industry in Hong Kong was completed in April 1991. The recommendations directly affecting the Survey and Mapping Office are now being examined for implementation.