Land Drains and Services

It investigates signals from below the ground to help identify possible drainage routes and buried services. Our service uses gradiometer surveying to look for relevant magnetic responses across the survey area.

Yes. Survey results can help reconstruct likely drainage patterns where records have been lost. The example on this page involved a farm of approximately 150 hectares whose detailed drainage maps were no longer available.

We use Bartington gradiometers to record magnetic variation. The resulting patterns are interpreted to identify responses that may relate to land drains or buried services.

Transects are survey strips positioned to cross possible features. Where suitable, they can help identify drainage or service patterns while reducing the area that needs detailed coverage and keeping survey costs down.

They can produce identifiable responses in suitable conditions. The example illustrated on this page shows a herringbone array of clay land drains, but the detectability of any particular system depends on its materials and surroundings.

No single geophysical method detects every buried feature. Some materials produce little magnetic contrast, and other signals may obscure a response. The survey scope and its limitations need to be considered when using the results.

This survey is intended to help locate possible drains and services. A magnetic response does not establish whether a pipe is blocked, damaged or flowing, so questions about its condition require a separate investigation.

A gradiometer survey does not normally provide a reliable direct measurement of pipe depth. Its main value here is identifying likely routes and patterns; any requirement for depth information should be discussed when agreeing the work.

No. This is a non-archaeological application of geophysical surveying. It can be useful to landowners and project teams trying to understand existing drainage or investigate possible buried service routes.

Send a plan showing the area, its approximate size and the purpose of the survey. Include any surviving drainage or service records, known access restrictions and details of the surface conditions so we can assess the proposed work.