2012:637 - River Avoca, Arklow, Wicklow

A non-disturbance assessment of a 30m-stretch of the Avoca River, Arklow Town, was undertaken as part of the Arklow Main Drainage Scheme. It is proposed to insert a Double Inverted Siphon at this location to convey sewage flows from the town’s southern side to its northern side, forming an integral part of the Arklow Main Drainage Scheme. The siphon crossing point was identified as an Area of Archaeological Potential (AAP2) in the Archaeological Assessment for the drainage scheme.
The area identified for underwater archaeological assessment (AAP2) measures 66m north-south, between quayside structures, and 30m north-west/south-east; 15m upstream and 15m downstream of the centreline of the proposed siphon.
A weighted baseline was laid across the river, along the centreline of the proposed siphon location at Area AAP2. This allowed the underwater survey to be carried out in a systematic manner and facilitated accurate recording and position-fixing of any material encountered. A detailed written record was made, supplemented by photographic documentation. Particular attention was paid to the existing river environment and detailed descriptions of riverbed topography were made.
No material of archaeological significance was encountered as part of the survey. Modern debris was noted within the matrix of a shingle deposit located on the southern side of the river. This material included 20th-century pottery fragments, red brick, and metallic debris. The central channel was largely free from surface debris, only mooring chain attached to risers and associated surface marker buoys being encountered. The mooring blocks/weights associated with these were not visible, having been naturally buried within the coarse sand that forms the riverbed. A series of floating pontoons, providing access to these moorings, run parallel to the North Quay, c. 2m south of the quay structure.
The assessment was comprehensive and extended beyond the potential siphon impact area as indicated. While no archaeologically significant materials/structures were observed, the possibility that archaeological material/structures lie buried within the riverbed still remains. This riverbed potential is attested to by the medium holding content present and the observed burial of the mooring blocks located within the survey area. The underwater assessment was carried out on 6 April 2012.

The Archaeological Diving Company Ltd, Brehon House, Castlecomer, Co. Kilkenny