Organization of Survey in Developed Countries (England, Canada and US) : Need and Ease of Air Survey (Especially for GATE-Geospatial 2022)

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Problems with Traditional Survey

Initiative in mapping is usually taken by the military authorities, who realize from experience the paramount importance of first-class maps. The greatest difficulty of the surveyor is that in most cases the civil administration will not incur much expenditure without immediate return and since reliable maps form an investment which pays but a small dividend at first, survey departments are frequently found struggling along with minimum staff and microscopic funds.

Air Survey: Problems and Solutions

  • Air survey enables a reliable topographical map to be produced in a few years instead of after two or three generations. Expense, spread over these few years is heavy, not on account of greater cost, but because the outlay is concentrated into such a short period.
  • Benefits to agriculture and industry are immediate, but the exchequer benefits only indirectly. There seems no doubt that in such cases, the cost of mapping should in part, at least, be shouldered by those who benefit the most, and one solution is to raise a “survey loan” repayable over a number of years. The cost can be distributed over the various departments concerned, such as survey, public works, geological survey, forestry, agriculture.
  • Air survey in this way rapidly provides the necessary scientific and economic data to further best the cause of empire development.

Survey in British Colonial Period: Imperial Survey Organization

General policy in the British Empire has been to encourage commercial enterprise regarding air photography and although the Royal Air Force has co-operated in numerous experiments, for most of the work contracts are left to the private firms.

It does not seem practical for any government department to set up its own special air photographic organization because the time of employment would be small.

An Imperial Survey Organization was first suggested a number of years ago by Hemming, who was supported by Salt (at that time Research Officer to the Air Survey Committee) in 1933; and later by others.

Progress in Surveying in Canada

Progress in Canada, in which photographic surveying was first practically applied, has been somewhat different (The writer is indebted to Mr A. M. Narraway, Consulting Aerial Surveys Engineer, Bureau of Geology and Topography, Ottawa, for most of this information) . The Topographical and Air Survey Bureau of the Department of National Defence has been largely responsible for the photography, although such other departments as the Bureau of Geology and Topography of the Department of Mines and Resources are also actively concerned. Photography has been carried out by the Royal Canadian Air Force as well as by private firms. A library of some 780,000 photographs is now available for various purposes and these are being extensively used. These photographs are available to the public as well as being used by the Topographical Survey, Geodetic Survey, Hydrographic Survey, Dominion Water Power and Reclamation Bureau, and the Forestry Department. Canada is in a rather special position, because the vast and inadequately mapped areas contain, particularly in the north-east, great mineral and other natural wealth. The vast nature of this problem has led to an organization which would hardly be justified elsewhere. On the basis that a photograph shows each tree, rock, exposure or stream, it is possible to go photograph by photograph and examine all these in detail from the Atlantic Ocean at Halifax to the prairies at Winnipeg; thence to and along the Arctic Coast - a distance of some 4,300 miles without a single breach. It is generally assumed that the average photograph will have some five official uses and each user is concerned only with his own share of the cost.

Progress in Surveying in United States

With regard to the United States, much progress has been made in air photography as shown by the sketch map in below Figure, by which it can be seen that up to 1 June 1938 someone and a half million square miles had been photographed, while contracts have been let for an additional 435,000 square miles. Also, some 55,000 square miles have been photographed in Alaska.

Unites State Map Location

In the case of the United States Geological Survey, up to the end of 1937,210, 313 square miles were photographed in the United States, and 22,000 miles in Alaska. Of these areas, 137,021 square miles had been compiled in planimetric maps in the United States and 16,315 square miles in Alaska. The total area contoured from air photographs was just less than 2,000 square miles.

The Soil Conservation Service of the Department of Agriculture has, since its inception in 1933, mapped some 400,000 square miles by air survey.

About two-thirds of the area photographed by the Department of Agriculture has been primarily for the Agricultural Adjustment Administration for the determination of crop areas and not for mapping purposes. The photographs are, however, available for other departments.

Although much progress has been made in the United States in the field of air photography and survey, there is, as is mentioned on page 51, some dissatisfaction there because of the lack of a real national survey programme.

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