Expert Trenching Solutions for Reliable Water Supply Installations

Trenching is carried out by mechanical back acting wheeled digger or tracked 360° digger, depending on field conditions.  They are excavated around or through each field in preparation for the installation of new or replacement permanent pipework to supply water to each field from the pumping system.  We always ensure that top soils are kept separate from the sub-soils so when backfilling the topsoil remains at surface level.

This service can be used to extend existing irrigation schemes or as a new complete project installation.

Trenches are dug sufficiently deep enough (usually 1.2 metres in depth) to avoid pipe damage from machinery such as sub-soilers or ploughs and also to prevent frost damage. High quality PVC pipe is then laid out and installed within the trench together with any bends, tees and hydrants that are required before all soils are backfilled.

Pipeline Design & Planning

An underground mains route is designed on a scaled Ordinance Survey map of the fields to be irrigated in order to supply water to each field in the most economical and efficient method. This takes into account water volume to be pumped, irrigation field lengths, cropping directions, and where hydrant take-off points are to be sited in each field, which would determine pipe sizes required.

Considerations are also given to the following points when planning an underground mains installation:

  • Number of hydrant take off points required (ground level connection taps)
  • Road crossings (public road crossings require a licence application to be completed)
  • Existing railway culverts (require special permission from the railway operator)
  • Crop planting directions
  • Utility services (Telephone, Water, Gas, Electric and sewer) all of which are located before trenches are dug
  • Any other site-specific circumstances

‘Mains supply’ refers to the main supply of water throughout underground pipes to the hydrant take off points and is in no way connected to the Local Water Authority ‘mains water supply’.


Once the route is agreed and approved – AJ Freezer can provide a quotation for the supply and installation of all pipework and materials using their own qualified employees and machinery..

  • Full turn-key solution for the supply of parts, materials and labour
  • Final stage – trenching and installation

Pipe Repairs & Leaks

Damage caused by machinery or corrosion due to age can cause valves to seize and pipes to break. Our engineers can carry out repairs or replacements to damaged steel hydrants and any broken PVC pipework that may occur.