A site investigation, in relation to construction, is the process of gathering and analysing information about a specific construction site to assess its suitability for a proposed project, identify potential risks, and inform the design, planning, and execution of the project. Site investigations are a crucial aspect of the pre-construction phase and provide valuable insights into the site’s geotechnical, environmental, and other characteristics that may impact the project’s feasibility, cost, and schedule.

Site investigations typically involve a combination of the following activities:

  1. Desk study: A review of existing records, maps, aerial photographs, and other available data sources to gather preliminary information about the site’s history, geology, topography, and environmental conditions.
  2. Site reconnaissance: A visual inspection of the site and its surroundings to observe and document features such as access, vegetation, drainage, and potential hazards.
  3. Geotechnical investigation: The study of the site’s soil and rock conditions through methods such as drilling, sampling, and laboratory testing to determine properties like bearing capacity, settlement potential, and slope stability.
  4. Environmental assessment: An evaluation of the site’s environmental conditions, including potential contamination, presence of protected species or habitats, and flood risk, among other factors.
  5. Utility surveys: The identification and mapping of existing utilities, such as water, gas, and electrical lines, which may impact the project’s design and construction.
  6. Topographical survey: The collection of accurate measurements of the site’s elevation, contours, and other physical features to create a detailed map or model for use in the project’s design and planning.

The findings from a site investigation are usually compiled into a comprehensive report that informs the project’s design, cost estimation, risk management, and construction planning. In the context of construction, site investigations play a critical role in reducing uncertainties, mitigating risks, and ensuring the successful completion of a project.