2026:012 - Athlone Solar Cable Route, Roscommon

Survey Area 1 was located towards the western end of the Proposed Development. The survey area was situated along the Mihanboy River within the Townlands of Mihanboy and Taduff East. It measured 25m in length by 5m in width. The survey area was fully accessible to the author during the inspection.
The water was quite fast flowing and the depth recorded within the river ranged from 0.4–0.6m. Visibility within the water column was good. The profile of the riverbanks were noted to be steep and rose sharply from the riverbed. The profile recorded was U-shaped. A measured profile across the width of the survey area was taken with the GPS. The riverbed was found to be rocky and compact. No metal finds or archaeological features/deposits were identified within the riverbed or along its banks. Several modern metallic pieces of rubbish (discarded disposable barbecue trays) were noted but were not logged with the GPS. No metal find spots or archaeological material was noted within the survey area.

Based on the results of the survey, this part of the Mihanboy River is determined to be of low underwater archaeological potential.

Survey Area 2 was located along a small stream which fed into the Cross River. The area inspected measured 30m in length by 7m in width. The route of the M6 motorway lay directly to the south of Area 2. The general vicinity of the survey area was very waterlogged and boggy. The stream was shallow at approximately 0.2m deep. The stream bed was mostly clay with occasional stones and the channel was approximately 1m deep from the top of the banks and 3m wide. The profile
recorded was V-shaped. A measured profile across the width of the survey area was taken with the GPS. There were no archaeological deposits, features or metal find
spots identified either within the stream or along both banks visually inspected and metal detector surveyed. Based on the results of the survey, this stream is determined to be of low underwater archaeological potential.

Survey Area 3 was located within the channel of the Cross River and comprised an area measuring approximately 40m in length by 6m in width. The general environs of
the survey area were characterised by marshy and waterlogged ground conditions, with dense vegetation and long grasses extending to the river margins. A modern concrete culvert was recorded on the northern bank of the river at the western extend of Survey Area 3.

The surveyed part of the Cross River was observed to be quite fast flowing at the time of inspection. Initial assessment established that water depths exceeded 0.75m across the majority of Survey Area 3. In response to these conditions, a standard wade survey methodology was employed, supplemented by a snorkel survey and probing within deeper sections of the river channel. The survey also incorporated systematic metal detection within the river and along the northern and southern riverbanks. The maximum depth measurements recorded during the survey was approximately 1.8m
at the midpoint of the river channel. Depths along the northern and southern margins of the channel generally ranged between 1m and 1.5m, with minor variations. The river channel was U-shaped in profile with vertical sides sloping concavely to the midpoint of the river. Visibility within the water column was consistently poor, measuring less than 0.3m throughout the survey area. Visibility was further reduced by sediment particles being carried in the current, the extensive growth of river grasses and vegetation extending across the riverbed and into the water column.
The riverbed within Survey Area 3 was characterised by a deposit of soft sediment and mud approximately 0.05–0.1m in thickness, overlying a compact stone and gravel riverbed. A snorkel survey was conducted along a series of parallel transects orientated in line with the river channel (east–west) to achieve systematic and comprehensive coverage. Transect spacing was adjusted in response to water depth, current strength and visibility conditions to ensure sufficient overlap and coverage of the riverbed.
No metal objects, metal find spots or other archaeological features were identified during the metal detection survey within the river channel and along the northern or southern riverbanks. Similarly, a snorkel survey and targeted probing did not identify any archaeological deposits, features or artefactual material within the surveyed area. It was not possible to record a measured cross-section profile of the Cross River, as the 1.8m depth at the midpoint of the channel exceeded the GPS receiver’s operational limits.
In conclusion, no archaeological features, deposits or artefacts were identified within Survey Area 3, either within the river channel or along its banks. Based on the results of the survey, this section of the Cross River is determined to be of low underwater archaeological potential.