SUBSEA jet trenching and excavation leader, Rotech Subsea, has wrapped up a key fibre optic cable lowering scope of work off the south east coast of England. Rotech’s sought after TRS1 LD controlled flow excavation (CFE) shallow water system was deployed from the company’s Aberdeen HQ to complete the trenching works.
The scope of work on this key communications link saw Rotech’s TRS1 LD conduct post-lay trenching of the 5km stretch of 32mm diameter cable to 2.0m Depth of Lowering. Starting at the shore – in 1.5m water depth – and supported by a DP Ultra Shallow Draft Support Vessel, the tool progressed along the route, with the water depth rising to 25m at the termination point.
Speaking about the latest UK outing, Rotech Subsea Director of Subsea, Stephen Cochrane, commented:
“This UK project was a great showcase for our bespoke TRS1LD shallow water controlled flow excavation system. Being able to deliver up to 2,600 litres/sec of controlled flow rate in water as shallow as just 1m the tool boasts soil cutting capabilities of 140kPa.
“The first part of this scope saw the team carry out a first pass over all areas with sand banks to level the area. A second pass was carried out excavating to 2m with a final flushing pass allowing the cable to sink to the bottom of the trench. Once completed, a TSS350 survey was carried out to verify the depths".
With its proprietary range of CFE Jetting & Hybrid Jetting tools, jet trenching and excavation pioneer Rotech Subsea has established itself as the cable trenching and seabed levelling partner of choice in Europe. The company’s research, development and engineering team has created a suite of sector-leading non-contact CFE, Suspended Jet Trenching tools in-house at its Aberdeen HQ. With enhanced capabilities, Rotech Subsea’s CFE & Hybrid Jet Trenching suite of tools is firmly established as the method of choice for offshore wind farm cable trenching and excavation in Europe and beyond.
Rotech Subsea has over 25 tools worldwide now and building more through our engineering division to fulfil 2024 commitments. Rotech is able to offer 14 next-generation spread types, having designed these CFE/jetting/cutting tools to meet market needs since 2015 leading to over 600 projects throughout the 30 years of experience at Rotech.
Rotech Subsea was also contracted to conduct follow on trenching works on the mainland Europe end of the communications cable.
Link: as reported in Aberdeen Business News, September 7th, 2023