Work begins to replace water mains pipe that runs under four lanes of A1 at Wittering

Anglian Water is using cutting edge technology to drill underneath the road, near RAF Wittering, in order to replace a section of water pipe.

As preparation for this significant engineering work Anglian Water, with specialist contractor Conway's, dug boreholes on either side of the A1 in October to profile the ground they are drilling through.

Fiona Hallam, Anglian Water Project Manager, comments: “The boreholes showed the ground underneath the road was made up of a number of different types of rock, so Conroy’s will use a drill specifically designed for rocky ground to complete the work.

“The technique we are using is called ‘Directional Drilling’. This method was chosen as it gives us better steering capability and accuracy - there’s no room for error when you’re drilling under a major road!

“Once the sleeve has been drilled using this directional drilling process, we’re using a specialist technique known as ‘slip lining’ to pull the new main pipe through the old one so no open trenches will be required in the carriageway. By using these two techniques we’ll be able to complete the work with no disruption to road users - obviously a big factor when planning work of this nature under an A-road.

“We started the project this week and we anticipate we’ll complete the work within 2 to 3 weeks. The relatively short distance we are drilling means we could normally complete this work in a few days, but the rock we’re drilling through means it will take longer."