2002:0688 - TALLAGHT–MIDDLE ABBEY STREET, LUAS Line A, Dublin

Monitoring along the 14km route of Line A (Tallaght to Middle Abbey Street) of the proposed light rail system continued in 2002. This resulted in further excavation at Ballymount Great undertaken by John Ó Néill in February (No. 462, Excavations 2002, 00E0538) and an investigation by the writer of an area along the centre of O’Connell Street in October (No. 569, Excavations 2002, 02E1825).

Monitoring along the route in the city centre has indicated nothing apart from the services that have been laid and relaid in recent years. Although this will come as no surprise to cyclists and motorists, it is likely that some archaeological material has been lost over this period, as none of these works appear to have been monitored. The amount of subsurface disturbance was significant from James’s Street right through to Abbey Street, and, as reported in Excavations 2001 (No. 359), there was only one area (at the corner of Abbey Street and Liffey Street) where extensive in situ deposits were encountered. Evidence of earlier services was recorded on James’s Street, where a 4m section of a timber water pipe had been displaced by a later water main. The bore had an internal diameter of 100mm (4in), which held a cast-iron pipe, and probably dates to the last quarter of the 18th century, when the water supply from the City Basin was upgraded.

Service works along St Mary’s Abbey necessitated the tunnelling of a 900mm-diameter sewer pipe underneath a large masonry wall for a length of 20m. This, on initial inspection, appeared to be a possible contender for the southern precinct wall of St Mary’s Abbey. Subsequent research of public utilities annotated on early editions of the OS have suggested, however, that the wall is part of a large Victorian sewer that ran underneath the centre of the street, although there remains the possibility that the sewer builders reused an existing structure.

A masonry well was recorded underneath Store Street that belonged to a house plot identified on John Rocque’s map of 1756. It was plumbed to a depth of 4.5m before collapse was hit.

The track construction was monitored along the length of the backfilled section of the Grand Canal behind St James’s Hospital and through the precinct of the old City Basin. The wetness of the ground necessitated ground reduction in excess of the usual 600mm required. No significant archaeological deposits were recorded, despite the evidence of medieval cultivation in the area.

Monitoring of construction works will continue until the end of 2003.

2 Killiney View, Albert Road Lower, Glenageary, Co. Dublin