Broadmarsh Ground Investigations Surveys

Havant Borough Council's (the council) Coastal Partners team invited tenders from a select list of suitably qualified and experienced suppliers to undertake Ground Investigation (GI) works at Broadmarsh Coastal Park.

The Council, as the landowner of the Broadmarsh Coastal landfill protection coastline, is in the process of developing a new, cost-efficient coastal defence at Broadmarsh Coastal Park. The aim is to establish a long-lasting solution that requires minimal maintenance while effectively protecting the historic landfill site. To support the development of a feasible and detailed design, the council intends to engage an external supplier to undertake Ground Investigation (GI) works.

Scope of Services

Generally, to provide geo-environmental and geotechnical investigation to inform the design of coastal landfill protection scheme. Works include intrusive exploratory holes, cone penetration testing, trial pits and associated laboratory testing and reporting as detailed in the Scope. Set out below are the key elements of the specification:

• Eight (8) cable percussion boreholes to prove ground conditions along the frontage and the materials used in the existing embankments. Two cable percussion boreholes may change to window samples due to access constraints.
• Installation of five (5) groundwater monitoring wells.
• Hand excavation sampling pits to 1.2m depth to collect samples of topsoil and soil within the embankment crest, landward toe and through blockwork revetment.
• Site investigations exploring conditions of existing features.
• Existing steel sheet pile investigations including magnetometer and ultrasonic tests.
• In situ standard penetration testing (SPT) / hand shear vane testing in borehole samples.
• geotechnical sampling (small and large disturbed and undisturbed samples) in exploratory holes.
• geo-environmental sampling in exploratory holes.
• laboratory testing (geotechnical and geo-environmental testing) on recovered soil and groundwater samples as detailed in the schedules and instructed by the Investigation Supervisor.

Only the factual part of the geotechnical Ground Investigation Report is to be provided by the Contractor.

The works will be administered though an NEC4 Engineering and Construction Shortform Contract (ECSC) and any change to the Scope and specification will be managed through the standard Compensation Event process.

The works will be delivered during April and May 2026.