Galliford Try MGjv team completes successful tunnel under M3

Galliford Try, as part of MGjv, has successfully reached a major milestone on Southern Water’s £100m Southampton Link Main project, following the completion of a key tunnel installation beneath the M3 in Hampshire.

The engineering team used a remotely operated tunnel boring machine over a 32-day period to create a 1.78m diameter tunnel, 456m in length and 7.6m under the motorway, forming part of the wider infrastructure of the project that will enhance drought resilience and secure water supplies across the county.

This newly completed section, is one of three designed to connect to Southern Water’s Otterbourne site near Winchester. The trenchless delivery approach ensured that motorists remained completely unaffected throughout the works.

Once the three-year programme is complete, the new pipeline will run from Otterbourne Water Supply Works to the Yew Hill reservoir, before continuing south to Rownhams Water Supply Works on the outskirts of Southampton.

Mark Shadrick, Managing Director for Galliford Try’s Environment business commented: “Our team is proud to have reached this key milestone, which marks important progress for the entire programme. This tunnel project plays a vital role in helping Southern Water improve Hampshire’s drought resilience, securing reliable water supplies while supporting the wellbeing of local waterways.

“We look forward to working with all the stakeholders involved to complete this much-needed infrastructure that will make such a significant contribution to local people.”