A topographical survey is a process that captures the details and contours of the land, including its various elevations, and depicts them in a three-dimensional perspective. These surveys are conducted by professional surveyors who use advanced technologies like GPS, drones, and laser scanning to create accurate representations of the land.

Phrased differently, a Topographical Survey is a 2-D representation of what is happening in the real world (3-D). The characteristics of a topographical survey can vary, but some of the most common elements include:

• Elevation Data – The digital representation of the Earth’s terrain is elevation data. This data can be represented using points such as x, y, and z. Or in the form of gridded formats also known as raster. This data is collected by utilising topographic survey equipment. The equipment includes GPS receivers, laser scanners as well as total stations.
• Contours – Contours or contour lines are the graphical representation of the elevation data. A contour line shows the peaks and the valleys of the land. For example, if there is a significant slope on a property, contour lines can be shown on the drawing to represent every time there is a drop of 1.5 vertical meter. A drop of 1 meter, 50 cm or even 25 cm can be shown as well, it is all based on the data that the land surveyor obtains while at the project. The smaller the cumulative drop, the more detailed the survey becomes.
• Survey Control Points – In the collected data, the established reference points are called survey control points. These control points have known coordinates attached to them to ensure accuracy and consistency in the data. Topographical surveyors utilise these control points for survey networking as this data enables precise spatial referencing and integration of data.
• Natural Features – Topography surveys also help in identifying the terrain’s characteristics that are natural such as valleys, hills, rivers, etc. In addition to that, areas with vegetation can also be determined by conducting topographical surveys. The surveyor can locate individual trees and bushes, the outer perimeter of a “brushy” area, and more info if required. This is important for us as we want the antennas to have unobstructed view in a circle of 360 degrees (above 20 degrees of elevation).
• Man-made Features – Along with the natural features, topographical surveys also help identify the man-made features present in a landscape. These man-made features can include roads, utilities, buildings and other developed infrastructures. Overhead utility lines, street lights, electric boxes, pipeline markers and any visible evidence can be shown on the drawing.

The data obtained at the property by the land surveyor will determine what the topographic survey looks like. The more data the land surveyor obtains, the more detailed a topographic survey can become.

It’s important to have a professional land surveyor explain the drawing and make the data easier to understand. They are, remember, taking a 3-D world and putting it on a 2-D product.

How a Topographical Survey is Conducted?

The process of conducting a topographical survey is a detailed one – covering a number of steps:

1. Planning & Preparation: This step of conducting the topo survey covers defining the survey objectives. The Topo surveyors identify the appropriate methods to conduct the survey. And then also prepare the suitable surveying equipment to get started.
2. Data Collection: This step takes the surveyors to the field where they are assigned to collect the required data. The process of data collection includes conducting on-site measurements and determining elevation data. Data collection also enables getting spatial information by making the most of the surveying instruments.
3. Data Analysis and Processing: The step of analysing the data and processing it allows going through raw data and then generating digital elevation methods (DEMs). The surveyors and other concerned individuals can then evaluate terrain characteristics by utilizing modern techniques and software.
4. Mapping & Reporting Processes: This step includes the creation of accurate and detailed topographic maps after data collection through land surveying, etc. We must also mention that this data also helps in determining contour plots as well as detailed reports to showcase survey findings.
5. Data Management: Land surveying is an ongoing process. What we mean to say is that all the data that has been collected through various surveys needs to be stored, updated and managed properly. When such careful steps are taken, the stakeholders can ensure a smooth project delivery while also keeping the data safe and present in one place.

Conducting topo surveys facilitates multiple operations and individuals during the lifecycle of a project. However, the process has some challenges and limitations attached to it. Let’s have a look at them to better understand the overall process.
Challenges and Limitations attached to Topographical Surveys
Topo surveys, no doubt provide access to interesting and insightful data when it comes to land surveying. We would like to mention that certain limitations can impact the results or the timelines such as:

• Complex terrain characteristics
• Harsh weather conditions
• Access restrictions
• Not having enough knowledge to utilize the surveying equipment