A site investigation is the process of gathering and analysing information about a construction site to assess its suitability for a proposed project, identify potential risks, and inform the design, planning and execution of the works. Site investigations are a crucial part of the pre-construction phase and give valuable insight into the site’s geotechnical, environmental and other characteristics that may affect the project’s feasibility, cost and programme.
Site investigations typically involve a combination of the following activities:
- Desk study: a review of existing records, maps, aerial photographs and other available sources to gather preliminary information about the site’s history, geology, topography and environmental conditions.
- Site reconnaissance: a visual inspection of the site and its surroundings to observe and record features such as access, vegetation, drainage and potential hazards.
- Geotechnical investigation: the study of the site’s soil and rock conditions through methods such as boreholes, trial pits, sampling and laboratory testing, to determine properties such as bearing capacity, settlement potential and slope stability.
- Environmental assessment: an evaluation of the site’s environmental conditions, including potential contamination, the presence of protected species or habitats, and flood risk, among other factors.
- Utility surveys: the identification and mapping of existing utilities, such as water, gas, electricity and telecommunications, which may affect the design and construction of the project.
- Topographical survey: the collection of accurate measurements of the site’s levels, contours and other physical features to create a detailed plan or model for use in design and planning.
The findings are usually compiled into a comprehensive report that informs the project’s design, cost estimate, risk management and construction planning. Site investigations play a critical role in reducing uncertainty, mitigating risk and supporting the successful completion of a project.
