EHG6068 - Watching brief - water treatment works, Loch Ashie

A watching brief was carried out by CFA Archaeology Ltd between September and November 2000 in advance of the construction of Inverness Water Treatment Works and Reservoir at the north end of Loch Ashie. The work was commissioned by North of Scotland Water Authority. The watching brief was undertaken during the initial topsoil removing phase of the development from the area of the building, reservoir and an access road between them. It was also removed from the car park, both screening mounds, a new development area access road, a temporary water supply pipe and various drains and minor construction necessities. Due to the discontinuous nature of the topsoil removal and the fact that the exact position of the new works were by then known it was possible to excavate sites by hand in advance of the arrival of the machines. Much useful work was done in this way during the watching brief. Overall, half of the drawings were done during the watching brief which occupied well over half of the time spent at Loch Ashie. Excavations on walls 48, 54, 80 and 82 were carried out at junctions and seemingly well preserved stretches of these walls. Most of the clearance cairns lost during the development were also recorded during the watching brief. As less subsoil was available from the deep excavations than had been anticipated the screening mounds were smaller and consequently fewer sites were lost than expected. Topsoil removal was undertaken using a 360° excavator employing either a toothed or a smooth bladed bucket as ground conditions allowed. Stony and thin topsoil made the use of a smooth bladed bucket impractical in places. In the area of the screening mounds, a specially adapted bucket to lift turfs without damaging them was employed. Subsoil, excavated from the reservoir and building bases was dumped onto the deturfed surface up to the required height. The turf was then replaced neatly onto the completed screening mound. A temporary Haul Road was created linking the reservoir and building excavations with the screening mounds. This operation was continuously monitored by the project archaeologist. <1>