East Ayrshire water supply tunnel complete

8 January 2018


Great Britain - The Caledonia Water Alliance (CWA) has successfully tunnelled beneath the A77 road and River Irvine in East Ayrshire, Scotland.

The joint venture, which comprises Morrison Utility Services and Aecom carried out a 1.2m-diameter, 60m-long TBM drive to house a 67m-long steel pipe.

CWA also installed a 70 metre-long stretch of tunnel, built out of 1.5 metre diameter concrete rings, about four metres below the river bed of the River Irvine west of Hurlford between the A77 and the B7073.

The tunnelling work, which started in mid-October and took five weeks to complete, was done without requiring any road closure or lane closure and so no disruption to traffic occurred. 

Client Scottish Water chose to highlight the benefits of tunnelling to the public, pointing out that open-cut methods would have called for road closure, negative environmental impacts and the diversion of a river.

Tunnelling work started in mid-October and took five weeks to complete. The project was part of a GBP 120M (USD 162M) investment in the region’s water supply.