In simple words, Topography is the study of the shapes, forms and features of land surfaces or the arrangement of the natural/artificial physical features of a particular area. In this article, we’ll look at what topographical surveys are and the importance of topographic surveys for various industries.

A. What is a Topographical Survey?

A Topographical Survey, also known as a Land Survey, measures and identifies the exact specifications and location of natural and man-made features of a particular land/area and its terrain. These include rivers, lakes, roads, reservoirs, forests, etc. In other words, the structure of a 3D world can be conveniently seen in a 2D paper sheet in the form of a topographical survey.

Benefits of Topographical Survey

• It provides you with a detailed and accurate view of a territory or plot.
• It greatly reduces the risks of costly errors caused by unforeseen factors.
• It provides the necessary data/information needed before you make any changes to a particular piece of land.
• It serves as a base map on which multiple parties can share their design work and other inputs.

B. Necessity/Importance of Topographic Surveys

Before developing a proposed land, it is critical to consider all factors under and around the land’s topography to map a successful development plan. Topographical surveys provide detailed, accurate information and comprehensive data that helps eliminate risks and the likelihood of failure once the construction or excavation project begins. Just like underground utility mapping, it prevents unnecessary expenses and delays. It also ensures there is no major setback during the construction phase.

The more data obtained by the surveyor, the more information you will have at hand to make the right choices. Below are some of the things that topographical surveys can help you identify.

• • Vegetation Position: Certain projects might require a survey of areas covered by dense forests or might need to determine the depth of large tree trunks or vegetation lines. Topographic surveys are very useful in this case. They help determine the size and type of tree. They help locate the vegetation lines. They also help determine what kind of vegetation can be suitable for that particular area.

• • Contour Levels: A topographic map generally emphasises the vertical shifts of lands or property that can be seen in a sequence of drawing contours. Contours make it possible to show the height and shape of mountains, the depths of the ocean bottom, and the steepness of slopes. There are three kinds of contour lines on a topographic map, namely: intermediate, index, and supplementary.

• • Natural Structures: Natural structures such as mountains, hills, lakes, cities, valleys, oceans, etc can be determined easily on a topographic map. During a topographical survey, elevations or height of these structures are recorded, generally with reference to the sea level (the surface of the ocean).

• • Man-made structures: Man-made structures such as houses, temples, hospitals, public transport lines, streets, and barriers can be easily spotted with this survey. This survey helps determine the exact location of these structures.

• Streams: Whether you want to locate a thread (centre line), or only the drawing banks of the stream or the lowest part (the thalweg), everything can be defined easily via a topographic survey.

C. Who Uses Topographical Surveys and Why?

Topographic surveys basically show elevations and land-forms not listed on traditional maps and surveys. These surveys also help reduce terrain-related risks. Listed below are some of its uses.

• • Engineers: For engineers, topographical surveys are immensely helpful. These surveys help them determine the changes needed to be made to a plot of land before they begin the construction work. This provides better stability for the said project. It also includes geotechnical investigations. Civil engineers use topographic maps to determine where and how far roads, tunnels or bridges should go. Additionally, while planning a housing project or making roads, an engineer needs to decide how much dirt or soil is needed to balance the plot’s elevation to make an even foundation.

• • Architects: Architects need accurate digital data to plan their projects with perfection. A detailed survey of all the features is critical and essential for planning, designing, and constructing. Any feature not surveyed can cause problems and lead to costly delays in the project development stage.

• • Government Agencies: Government agencies frequently utilize topographic surveys when analysing and evaluating a potential environmental restoration project. This type of survey also helps them establish regulations for construction in a particular area.

• • Forestry: Forestry industries use topographical surveys to make maps so that it becomes easy for forest rangers to travel in the forest with exact locations and specifications in hand.

• Construction Industries: In the construction industry, topographical surveys play a significant role, especially when the land poses noticeable challenges in terms of man-made structures, hills leftover from a prior construction, etc. These are certain instances when a topographic survey should be conducted before starting a new project. This ensures the proposed design for the project is implemented without any issues from the existing conditions of the land. 3D laser scanning survey provides highly detailed and accurate data for construction projects.

D. Planning a Topographical Survey

Mentioned below are a few commonly used methods for planning a topographic survey. A particular method is picked based on a specific area or terrain. These methods are carried out by professionally trained surveyors to ensure there is no error in the data collected.

Main Methods Used in Planning a Topographical Survey

• • Traversing: Traversing is a surveying method used to establish control networks. A traverse line is a series of straight lines connecting traverse sections that are established along the survey route. It follows a zigzag course which implies that it changes directions at each traverse section. This surveying method is used for flat or wooden terrain.

• • Radiation: In the Radiation method, the plane table is set up over only one section from which the whole traverse or traverse lines can be commanded. This method is apt for small survey areas.

• • Offset: In this method, horizontal distances are measured. In construction, short distances are usually measured, and the offset method is used to survey the details of the terrain, generally less than 35m long. The terrain can be rocks, well, or trees that are situated close to the chaining line.

• Triangulation: This method is used for hilly or open terrains with high vegetation, inaccessible locations and large land areas where traversing would be difficult. If you want to locate points on the opposite side of a lake or stream, then the triangulation method is useful.

Conclusion

Safety is an extremely important reason why topographic surveys are used. You need to partner with an experienced topographical survey provider to get reliable and accurate data on a piece of land before the start of a project. At Gulf Testing Solutions Enterprise LLC, we provide certified, full-spectrum land surveying services for public and private-sector clients. We make use of the latest survey equipment and methods to deliver error-free results to all our clients. Irrespective of the project size and complexity, we can provide the best-in-class topographical surveying services at a quick turnaround time.

So, connect with us now if you want to work with us on your next project!