Rotech Subsea delivers North Sea sandwave clearance and cable recovery

Subsea, trenching and excavation specialist Rotech Subsea has completed a sandwave clearance and cable recovery in the English North Sea for an engineering and underwater services provider.

Rotech’s next generation controlled flow trenching and excavation TRS2 tool carried out the sandwave clearance while its RSG tool completed the cable recovery.

The completed scope of works adds to Rotech’s European track record in renewables.

The cable remedial works required Rotech Subsea to clear a suitable corridor to Mean Sea Bed Level to allow access for the client’s Track trencher.

The project saw Rotech’s subsea spreads of equipment operate in water depths of between 9-18 metres. Sandwave clearance left a corridor between 9-10 metres wide for the track trencher to enter. This took place in two passes at a vessel speed of 4m/min in dense sand soils.

The TRS2 also found its use in SIMOPS to rebury approximately 3 kilometres of cable. The RSG grab operations were also a success, according to Rotech Subsea. The grab pulled the cable free from the sea bed allowing the client to cut the cable for recovery.

“Increasingly, we are seeing our RS range of Controlled Flow Excavation (CFE) and Suspended Jet Trenching tools being the ‘go to’ choice for IRM scopes like this,” said Director of Subsea, Stephen Cochrane. “Our trenching speeds are more than double that of competing Mass Flow Excavation providers, owing to the enhanced jet power the RS tools deliver and our team is adding to their unrivalled experience in the field on a weekly basis.”

Rotech Subsea said it also recently mobilised from the UK for Asia on three major IRM scopes, despite there being other older technology available to both clients in-country.