Groundwater Monitoring and Ground Investigation

In this post as part of World Water Day we look at how the hydrology and hydrogeology of an area can  impact on any construction project.

Regulators are often concerned with the impact a project will have on the groundwater of an area. The risks associated with a high groundwater table can cause all manner of issues to any project. An understanding of the groundwater regime of a site is a vital part of many different types of projects and is often necessary for foundation design, earthworks, basement impact assessments/design and contamination risk assessments.

It is important that any ground investigation takes into account and highlights the potential issues that are associated with the presence of both surface and groundwater. This can be achieved through a phased approach which should include the implantation of a comprehensive Phase 1 Desk Study. Our Phase 1 Desk Studies include hydrological data relating to Flood Risk (from Surface water, Rivers and Reservoirs), Aquifer designation of both the superficial (if present) and bedrock strata, whether the site is located in or near a Source Protection Zone (SPZ), information on local groundwater abstraction licences and the proximity and direction of any surface water features. All of this information is important for undertaking site specific risk assessments, relating to both geotechnical and geoenvironmental risk.

The findings of the desk study will assist in the planning of the initial site/ground investigation phase to include the installation of groundwater monitoring wells and long term groundwater monitoring (if required). It should always be noted that groundwater levels vary considerably from season to season and year to year, often rising close to the ground surface in wet or winter weather, and falling in periods of drought.  Long-term monitoring from boreholes or standpipes is often required to properly assess the groundwater regime.

At Southern Testing we regularly use data loggers when undertaking long term groundwater monitoring. The data loggers can be set to record water level readings from intervals between 5 seconds and 24 hours, meaning that continuous data can be recorded and saved in order to be downloaded and analysed at a later date, providing a reliable data set spread over a period of weeks, months or years. The data loggers can reduce the need for additional site visits and can be downloaded at the same time as any gas monitoring visits, or fitted with telemetry capabilities to allow remote access.

For further information or any enquiries regarding theany of the above please contact us enquiries@southerntesting.co.uk