2016:138 - Townparks, Swords, Dublin

Test trenching took place from 11-16 March 2016, using a 13-tonne tracked excavator equipped with a flat, toothless bucket under supervision. A total of 17 trenches were excavated within the area of proposed development. Test trenching followed on from a geophysical survey of the site that was carried out by Joanna Leigh under licence 16R0035.

The natural topography of the proposed development area has been subjected to considerable change over several hundred years. Test trenching illustrated that the western half of the site is located upon a ridge of bedrock and boulder clay which occurs c. 0.4m below the present ground surface. However, a natural scarp in the topography occurs along a line which runs roughly north-south through the centre of the site. To the east of this scarp, the natural ground level slopes steeply towards the River Ward with areas of sheer bedrock in places. This whole eastern portion of the site has been subjected to a process of landfill and reclamation, which appears to have commenced in the medieval period and continued into modern times.

Southern Plot

To the rear of the upstanding house in the southern plot (built c. 1800), a deep deposit of modern fill comprising of redeposited boulder clay and construction rubble was identified to a depth of 2m. The earliest deposit recorded was a dump of kitchen midden material which overlies steeply sloping boulder clay along the southern boundary of the site. This was partially overlain by a layer of dumped 19th-century material, itself overlain by modern 20th-century infill. As the natural ground level descended towards the river, the reclamation and levelling deposits become deeper. The instability of this material which gave rise to frequent trench collapse beyond a depth of c. 2.4m. The dumping of medieval domestic, kitchen waste downslope in the southern portion of the site is suggestive of medieval settlement further upslope at the site of the Vicarage to the south of the proposed development area.

To the immediate north of the 1800 house the remains of a stone-built cellar with cobbled floor were identified that correspond to an outbuilding represented on the first edition OS mapping. The walls of this structure are relatively thick (0.8m) and are built of coursed local limestone slabs and bonded with a yellow-white lime mortar. No brick or brick fragments were visible in the wall fabric however, a c. 17th-century floor tile fragment was retrieved from the lime mortar, as was a sherd of 13th-century ceramic.

Central Plot

Boulder clay and bedrock were encountered in the western part of the plot at c. 0.4m below present ground level. A rock-cut ditch (C1) was identified, orientated north-east/sout-hwest on an alignment that may travel between the medieval ecclesiastical site to the south and Swords Castle to the north-east. The ditch was not present in the trenches opened immediately to the east. It is suggested that C1 terminates at a steep natural scarp in the underlying limestone bedrock c. 3m to the east of Trench 10. It is possible that the original course of the River Ward was significantly wider at this location during the medieval period and ran along the base of this scarp c. 20m west of its current course. The channel was perhaps then narrowed in order to be able to construct a bridge across the river. A modern house and outbuilding have been constructed on the projected path of C1 to the west and south-west. It is estimated therefore that ditch C1 may survive for a length of c. 20m, running beneath the current lawn.

A 19th-century gulley observed in Trenches 11 and 8 has been interpreted as a drainage gully running alongside the former roadway visible on the first edition OS mapping. To the east of the balustrade wall, trenching revealed a natural scarp of limestone bedrock that would have once formed the western edge of the river channel. To the east and south of this scarp, reclamation deposits had been dumped into the former river channel in the 18th/19th century. Water ingress occurred at c. 1.8m below present ground level. An area of lime mortar was identified c. 0.8m below present ground level towards the current river bank.

Northern Plot

While a significant difference between the ground level in the east and west of this plot was observed, the profile of the slope from west to east was observed to be gentler than in the other plots. To the west of the upstanding house, natural boulder clay was encountered at c. 0.4m below present ground level. To the west of the house, c. 1m of imported 18th-19th-century garden soil was encountered overlaying limestone bedrock. In the central part of the plot, a surface of packed stone and clay (C10) was identified along the same orientation as the southern plot boundary. This corresponds to the location of the former roadway visible on the first edition OS mapping. In the eastern portion of this plot, a large amount of modern rubbish and overburden overlay the present ground surface. The topsoil in this area was much shallower than it was to the west (c. 0.4m). This overlay an area where two robbed-out/disturbed stone walls ran north-east/south-west (C9). An area of packed stone and clay was identified in an area defined by these two walls (c. 4m x 2m exposed). It is possible that these remains are associated with small post-medieval structures marked at this approximate location on the first edition OS map. This material overlay reclamation deposits with water ingress occurring at c. 2m below present ground level suggestion that this area was also formerly within the river channel. A cobbled surface was identified at the same level as the packed stone/clay surfaces along the line of the plot boundary between the northern and central plots. This well-made surface of fist-sized, edge set cobbles (C6) exhibited a linear depression that may be a wheel rut resulting from repeated use.

Unit G1, Network Enterprise Park, Kilcoole, Co. Wicklow