1999:455 - KILKENNY: River Bregagh at St Francis's Abbey Brewery, Kilkenny

Archaeological survey and the inspection of engineering test-pits were undertaken along the Breagagh riverbed where it crosses through St Francis's Abbey Brewery, Kilkenny, in order to establish a baseline against which the impact of proposed excavation works on the riverbed could be measured for archaeological and conservation purposes.

The riverbed level is to be reduced by bulk excavation to remove residual PCB contamination before the commencement of work on the Office of Public Works River Nore Flood Alleviation Scheme, which will also involve works in the River Breagagh. The PCB contamination was substantially cleaned up at the time of a spillage from a refrigerated unit over twenty years ago and has remained stable ever since, but removal of any surviving contaminated material is now required to prevent its movement and spread, through scouring action, after the reduction in level of the Nore as part of the flood-relief scheme.

The river and the masonry wall along its southern side formed the boundary of the medieval friary precinct, which, like other ecclesiastical establishments, was located at the limits of the town. The precinct of St Francis's Abbey occupied the north-eastern sector of the medieval Hightown, bounded by the Breagagh River on the north and the Nore on the east. Originally known as the North Quarter, it was owned by the bishops and only ceded to the Marshalls in 1207 (Thomas 1992, 131–2). Because of its function within the medieval town, and as part of the friary boundary, the river is a significant archaeological feature, and its deposits have significant archaeological potential.

The masonry wall on the southern side of the river was probably first built in the 14th century. It has been altered and repaired in antiquity, especially during the 17th century, and more recently and substantially as part of the development of the modern brewery facility. The masonry wall extended from, and formed part of, the circuit of medieval town wall in this location. A small defensive tower, Evan's Tower, stands at the confluence of the Breagagh with the Nore, and the wall does not appear (from present inspection) to extend along the bank of the Nore. There are no records apart from Rocque's map to suggest that the Nore river frontage ever possessed a wall.

In all, six test-pits were opened, primarily to assess the depth of the medieval wall foundations but also to establish the nature and content of the deposits on the riverbed. These were excavated in pumped, sand-bagged locations roughly 1–1.5m2, which remained dry in the relatively shallow water flow of the river. Of these, four were opened along the medieval wall and two were opened on the opposite side adjacent to the modern concrete wall. The first attempted pit was abandoned because of an inability to control the water flow (all pumped water had to be tanked for disposal offsite). The exposed riverbed was composed of gravel and small washed stones with occasional larger blocks. On either side, banks of gravel and sands have accumulated in three locations. These had significant reed growth on them at the time of survey, and their vegetation-covered surfaces had a high silt content.

Excavation on the southern side, against the medieval wall, revealed that the gravel extended down for at least 0.8–1m and that it possessed modern debris to that depth. No medieval material was noted in any of the material excavated along this side, although large quantities of modern bottles, some delph, plastics and some metal objects were removed for identification. This material, along the medieval wall, appears to be quite modern, and the gravel and sands have been significantly and dynamically reworked.

On the opposite, northern, side the profile differed. In both pits a thin spread of gravel overlay a virtually stone-free, organic-rich silt (exposed to the limit of excavation), which yielded two fragments of medieval ceramics. This was interpreted as the primary riverbank, wh ich has seen very limited erosion or reworking in the area investigated.

A second phase of investigation involved the examination of trial borings. These were monitored by Paul Stevens (see No. 456 Excavations 1999).

Reference
Thomas, A. 1992 The walled towns of Ireland (2 vols). Dublin.

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