Ground Investigation Begins Along the Southsea Seafront

From Monday, 9 September, ground investigation work will be taking place along the Southsea seafront as part of the next stage of designs for new coastal defenses, according to the official Southsea Coastal Scheme project website.

These investigations will take place over a period of four weeks at two locations, on the promenade and beach adjacent to Long Curtain Moat and Clarence Pier car park as well as to the east and west of Southsea Castle.

“We will be using borehole rigs, excavators and dynamic probes as part of the work which will allow for the design to be further refined as part of the detailed engineering design phase of the project,” their statement reads.

Various types of machinery will be used as part of the work, however this is purely for ground investigation and isn’t part of construction of the defenses themselves.”

Types of investigations:

  • Cable Percussive Borehole – This is the most common type of investigation method used. The rig uses a weight to drive a 15cm diameter casing into the ground. This casing is then pulled back up to retrieve a core which is sent to the laboratory for analysis;
  • Trial pit – Slightly larger holes are dug in the ground to allow the various layers of ground to be examined and further testing of materials if needed. These holes are then re-surfaced once the investigation is complete;
  • Ground Penetrating Radar – This method uses radar signals to identify buried objects and voids beneath the ground.

The Southsea Coastal Scheme is a Portsmouth City Council project being delivered through the Eastern Solent Coastal Partnership.