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1.10. The Field of Surveying and the Role of the Surveyor

In its broadest sense, the term surveying encompasses all activities that measure and record information about the physical world and the environment. The term is often used interchangeably with geomatics which is the science of determining the position of points on, above or below the surface of the earth.

Humans have been undertaking surveying activities throughout recorded history. The oldest records indicate that the science began in Egypt. In 1400 BCE, Sesostris divided the land into plots so tax could be collected. The Romans also made significant developments in the field with surveying a necessary activity in their extensive building works across the empire.

The next period of major advancement was the 18th and 19th centuries. European countries needed to accurately map their land and its boundaries, often for military purposes. The UK national mapping agency, the Ordnance Survey was established at this time and used triangulation from a single baseline in the south of England to map the entire country. In the United States, the Coast Survey was established in 1807 with the remit of surveying the coastline and creating nautical charts in order to improve maritime safety.

Surveying has progressed rapidly in recent years. Increased development and the need for precise land divisions, as well as the role of mapping for military requirements have led to many improvements in instrumentation and methods.

One of the most recent advances is that of satellite surveying or Global Navigation Satellite Systems (GNSS), more commonly known as GPS. Many of us are familiar with using sat-nav systems to help us find our way to a new place, but the GPS system also has a wide range of other uses. Originally developed in 1973 by the US military, the GPS network uses 24 satellites at an orbit of 20,200 km to provide positioning and navigation services for a range of applications such as air and sea navigation, leisure applications, emergency assistance, precision timing and providing co-ordinate information when surveying.

The advances in air, space and ground based surveying techniques are in part due to the great increase in computer processing and storage capacity that we have seen over recent years. We can now collect and store vast amounts of data on the measurement of the earth and use this to build new structures, monitor natural resources and help develop new planning and policy guidelines.

There are several types of surveying:

Land Survey: The primary role of the land surveyor is to find and mark certain locations on the land. For example, they could be interested in surveying the boundary of a certain property or finding the coordinates of a specific point on the earth.

Cadastral Land Surveys: These are related to land surveys and are concerned with establishing, locating, defining or describing the legal boundaries of land parcels, often for the purpose of taxation.

Topographic Surveys: The measurement of land elevation, often with the purpose of creating contour or topographic maps.

Geodetic Surveys: Geodetic surveys locate the position of objects on the earth in relation to each other, taking into account the size, shape and gravity of the earth. These three properties vary depending where on the earth's surface you are and changes need to be taken into account if you wish to survey large areas or long lines. Geodetic surveys also provide very precise coordinates that can be used as the control values for other types of surveying.

Engineering Surveying: Often referred to as construction surveying, engineering surveying involves the geometric design of engineering project, setting out the boundaries of features such as buildings, roads and pipelines.

Deformation Surveying: These surveys are intended to ascertain whether a building or object is moving. The positions of specific points on the area of interest are determined and then re-measured after a certain amount of time.

Hydrographic Surveying: This type of surveying is concerned with the physical features of rivers, lakes and oceans. The surveys equipment is on board a moving vessel with follows pre-determined tracks to ensure the entire area is covered. The data obtained are used to create navigational charts, determine depth and measure tide currents. Hydrographic surveying is also used for underwater construction projects such as the laying of oil pipelines.

The requirements for becoming a geomatics surveyor vary from country to country. In many places, you need to obtain a license and / or become a member of a professional association. In the U.S., licensing requirements vary between states and in Canada, surveyors are registered to their province.

At present, the UK suffers from a shortage of qualified land / geomatics surveyors and many organisations have struggled to recruit over recent years.

In the UK, a graduate surveyor's starting salary usually ranges between £16,000 and £20,000. This can rise to £27,000 - £34,000 ($42,000-$54,000) once chartered status is achieved. Chartered status is gained from either the Royal Institute of Chartered Surveyors or the Chartered Institute of Civil Engineering Surveyors. A Masters degree is useful but not essential. Postgraduate qualifications also allow the opportunity to specialise in a specific area of the industry such as geodetic surveying or geographical information science. Entry to the industry with a foundation degree or Higher National Diploma is possible at lower levels such as assistant surveyor or in a related technician role.