2024:655 - Ballymakaily EdgeConneX, Dublin

Archaeological monitoring was carried out for groundworks associated with the development of a c.2.2km 110 kilovolt underground transmission line (and associated and ancillary works). The works were carried out on an intermittent basis between 8 February 2024 and 7 August 2024.

The c.2.2km line connected the Kishoge 110 kilovolt Gas Insulated Substation to the Aungierstown–Castlebaggot underground 110kV transmission line. The development passed through the townlands of Ballymakaily, Clutterland, Grange, Ballybane, Kilmactalway, Milltown and Aungierstown and Ballybane, County Dublin. For ease of reference the scheme was referred to as Ballymakaily EdgeConneX, Co. Dublin.

As recommended by a preceding Environmental Impact Assessment Report for the scheme, archaeological monitoring was carried out for all ground disturbance associated with the works in the greenfield areas, and an intermittent brief in the remaining areas of the scheme was kept to confirm levels of known/suspected disturbance.

Construction works for the underground transmission line comprised the excavation of a T-shaped trench (in profile) for c.2.2km. The T-shaped trench was created via the excavation of an initial c.3.8m wide x 0.5m deep trench, with a central section (c.2.2m wide) excavated a further 0.9m to 1.4m below ground level. Sections of the underground transmission line comprised directional drilling and required wider areas of ground clearance (c.25m x 25m x 0.5m depth) for launch pads. Ground clearance was also required for a temporary carpark (c.40m x 20m x 0.5m).

The only feature of an archaeological nature uncovered during monitoring was a vernacular structure located in the townland of Grange (bordering Clutterland) at Chainage 1250m (ITM: 702645, 731147). The structure was rectangular in plan measuring 5.2m north-northeast/south-southwest by 15.75m. The structure appeared to be a “byre” or cowshed (or in Irish – a bóitheach). Built of roughly hewn limestone blocks, with a lime mortar bond, and brick in parts, it  dated to the early 1800s and was likely to have been connected to a farmhouse structure depicted on historic mapping to the immediate northwest. The building showed signs of modification with twentieth-century breeze block, metal, cement, and concrete flooring. A mitigation strategy of preservation-by-record in advance of demolition and further monitoring of the area was agreed in consultation with the NMS and the Planning Authority and duly carried out.

No further archaeological features were uncovered during the monitoring of the scheme and no further archaeological works were recommended following its completion.