Farrans Construction - Belfast Sewers Project 

The Project involved the construction of a new stormwater management sewer, connected by overflow weirs to the existing Victorian network. The new sewer system is 9.4km in length with tunnels ranging in diameters from 1.5m to 4.0m. The larger tunnels were constructed using Earth Pressure Balance Tunnel Boring Machines. The smaller bores were formed by pipejacking methods. Depths of tunnels vary from 10 to 35m below ground. The associated access shafts (19 No.) were sunk using jacked caisson methods with diameters up to 12.5m.