PHYSICAL GEOGRAPHY

INTRODUCTION TO ELEMENTARY LAND SURVEYING

Land surveying is defined as the process by which measurement of land is made and then represent such measurement by tables, plans or layout for specific purposes.

It can also mean the measuring and mapping out of the position, size and boundaries of an area of land.

 

IMPORTANCE OF LAND SURVEYING

  1. Land surveying helps to determine the area of a place e.g. market, garden, school, etc.
  2. It helps to set on the ground the position of construction or any engineering works.
  3. It can also help to determine the production of maps.
  4. Land surveying can also be used to determine the relative positions or features of the earth (natural or artificial) so that they may be correctly represented on maps.
  5. Land surveying can be used as a basis of feasibility studies in any construction work to be carried out on the surveyed land.
  6. Land surveying gives the owner of the land security which can be used to obtain loan as soon as Certificate of Occupancy (C of O) is given.

 

BRANCHES OF LAND SURVEY

They are different branches of land survey. These are:

  • Topographic survey: In topographic surveys, the survey works are based on the different locations of the main, natural or artificial features of the earth, such as rivers, hills, valleys, villages, roads etc.
  • Engineering survey: These surveys include all aspects involved in the preparation of engineering works to its execution. The features mostly considered are roads, channels, rails, dams and other construction works.
  • Geodetic survey: These are high accuracy surveys mainly concerned with the shape of the earth or position, fixing of points which provide control for lower accuracy survey.
  • Geological survey: These have to do with features associated with the inner structure of the earth e.g. type of soil, water table, mineral content, etc.
  • Geographical surveys: These involve the surveying of natural and man-made features of the earth e.g. market, road, school, hospital, rivers, mountain, etc.
  • Cadastral survey: These surveys works based on the preparation of plans, indicating and defining the legal property boundaries.
  • Military survey: These involve the survey of land, air and water bodies to provide adequate information for the purpose of defense.

 

TYPES OF SURVEYING

There are many types of land surveying. These include:

  1. Chain surveying.
  2. Transverse surveying.
  3. Aerial surveying.
  4. Triangular surveying.
  5. Triangulation surveying.
  6. Plane table surveying.
  7. Hydro-graphic surveying.

 

COMMON SURVEY INSTRUMENTS

  • Ranging pole.
  • Measuring tape.
  • Offset staff.
  • Station peg.
  • Optical square.
  • Gunther’s chain.
  • Arrows or pins.
  • Steel band.
  • Watkin’s clinometer.
  • Field book.