A topographical survey is used to produce a detailed map of all man-made and natural features within a given area. Also known as a land survey, they are used to inform a variety of property management, development and redevelopment projects. In addition to planning purposes, a survey might also be needed for record keeping. Data collected from a survey is used in variety of plans, from standard drawings or plans on paper to advanced 3D digital models.
Purposes of a Topographical Survey
A survey might be needed for a variety of record and planning purposes. Surveys are then used by architects and builders to develop or redevelop the land or property on the site. They can also be used for modelling and visualisation purposes, or simply for maintaining historical records for the site. A survey might also be used to help manage and monitor a site, for example to help manage and mitigate land erosion.
Surveys might be needed for various projects, including designing a road or highway, railway, airport, housing estate, or commercial development. Surveys may also be needed to obtain the location of neighbouring properties and boundaries when dealing with the placement of a party wall or the sale and acquisition of land. Surveys are also helpful for locating specific details about an area, such as the location of trees and tree canopies or any surface features and services that might affect a property or the development of the land.
What’s Included in the Survey
A topographical survey measures the boundary, height and features of an area of land including the area around an existing structure. Typically, a survey will include measurements for any existing buildings and structures on the site. It will also include details on the boundary of the site. Information on the terrain will also be included, such as a grid of levels, ground surfaces, and the position of shrubs and trees. A typical survey also includes all utilities and services on the site such as drainage details and the position of service covers or manholes.
A survey may also include additional detail beyond the boundary of a site, such as the location of utilities including utility poles and manholes that might affect the site being surveyed. The survey might include the location of nearby trees and buildings that could also affect the project. Additional details can be included depending on individual needs, such as details and measurements on any features next to the site or underground services and features. Generally, surveys with a higher level of detail will cost more than one with less information.
Determining the Level of Detail
The amount of information included in a land survey often depends on individual project and client requirements. The details included in the survey are informed by the area that is being surveyed as well as the detail and accuracy required. For example, a survey based on a scale of 1:100 will be more accurate than one done to a scale of 1:200 or 1:500. The scale will also determine the level of detail that will be included. The information that is presented in the survey will also depend on how the data will be used and how the survey relates to the pre-determined grid and datum. Clients should always speak with land surveyors about their requirements before the survey is undertaken, including the extent of the survey area and the level of detail required.