GPR, utility and topographical surveys in Southampton

What the survey finds

Where we work in and around Southampton

We cover the whole city, from the city centre, Ocean Village and the old town to Shirley, Portswood, Bitterne, Woolston and Sholing. We also work across the towns around it, including Hedge End, Botley, Hamble, Totton, Romsey and the Waterside.

Eastleigh is on our doorstep, and we cover the town, the airport and business parks, Chandler's Ford, Bishopstoke and Fair Oak as local work.

Being local helps on small and urgent jobs. A short survey to clear a coring position or a drainage trench is easier to fit in, and costs less in travel, when the team is minutes away rather than hours.

Three surveys, one team

• Topographical surveys give architects and engineers a base drawing of levels, buildings, boundaries and features for planning and design.
• Underground utility surveys trace buried services with electromagnetic location and GPR, drawn to PAS 128.
• GPR surveys find voids, obstructions, reinforcement and other buried features.

On many sites we do the topographical and utility survey together. One visit produces a single CAD drawing with the surface features and the buried services in the same coordinates.

What Southampton jobs usually involve

Typical sites include:

• housing, school and care home schemes on infill and brownfield plots
• port, industrial and warehouse sites, where slabs and yards are cut for new drainage, ducts and machinery bases
• university, hospital and campus sites with dense, often poorly recorded services
• streets and estates being resurfaced or re-plumbed

We also help homeowners and small businesses, for example to check a garden or driveway for voids or to locate drains before an extension.

Ground conditions in Southampton

Southampton sits on a mix of sands, gravels and clays, with river gravels along the Itchen and Test. Around the docks and the waterfront, much of the ground is made ground on reclaimed land. Older parts of the city have been rebuilt many times over, so the ground is often full of rubble, old foundations and abandoned services.

These conditions affect GPR. Sands and gravels let the signal reach useful depths. Clay and wet, salty ground near the water absorb it, so depth is reduced. Rubble-filled made ground produces clutter that takes experience to read. We assess the likely conditions when we quote, and the report states what depth we achieved.

In the medieval old town, buried walls, cellars and vaults are common. Where a site has heritage interest, GPR can map features without disturbing them. See our archaeological GPR survey page.

How the survey is done

We agree the survey boundary and what you need to know, then scan the area in a grid or with GNSS positioning. For services, GPR is combined with electromagnetic location, which identifies live cables and metal pipes that GPR alone cannot name. Findings can be marked on the ground and are drawn up in CAD with a report, normally within 15 working days.

Questions we're asked