Seawater Life Support Project.
Water inlet pipe and Marine Mattress Installation managed by Structural Evolution
Project Overview
This Advanced Marine Conservation and Research project features a state-of-the-art seawater life support system for the Marine Biological Association's (MBA) Research Aquarium. It includes a 27-meter 3” Polyethylene (PE) intake line designed for consistent seawater intake, irrespective of tidal changes, enhancing research conditions.
The intake line is protected by ARC Marine's Marine Matts, made from carbon-neutral Marine Crete, which protect the line while promoting local marine biodiversity. The installation method also incorporated ScaffFloat’s floating barges, utilising recyclable plastic floats and scaffolding to construct a specialised floating barge for the installation of the 40 tonnes matt and pipe assembly. This approach made use of the high and low tides, as an alternative to using cranes and minimize the overall cost and environmental footprint.
Deployment Strategy
The near shore site location required a meticulously organised and well-planned installation methodology.
Structural Evolution successfully managed the mobilisation and installation of the new water inlet system and Marine Matts in an intertidal environment. The deployment required precise hour by hour planning to meet both logistical and tidal constraints, ensuring smooth execution and risk mitigation according to CDM 2015 regulations.
Tidal Window Optimisation
The deployment was strategically planned over spring tides, maximising tidal ranges to float the mattresses and minimise pontoons’ sinking requirements. Key dates with optimal tidal and weather conditions were identified, enabling daylight deployment, and reducing operational risk.
Mobilisation and Set-Up
MDL Marina provided access to their slipways for assembly and launching, this site was strategically chosen for its proximity to the installation location and access to the sea, so that assembly and launching of the water intake line and floating pontoons could take place close to the installation site.
The mobilisation area was carefully planned to accommodate the set-up and assembly of the inlet pipe and mattresses.
A 30m x 5m area was designated, with additional space for work access, subject to coordination with landowners. The deployment required a minimum water depth of 1600mm at high tide, at the shallowest end, to enable the Scaff-float pontoon, water intake line, and mattresses assembly to float effectively.
Installation Methodology
To stabilise the buoyant PE pipeline during transit, natural fiber ropes were utilised to secure it at multiple points along the mattresses. The ropes were looped around the pipeline, threaded through mattress gaps, and tied to connecting wires, ensuring stability while allowing the ropes to decompose naturally post-installation, mitigating the need to work under water to remove the ropes.
The Scaff-float pontoons were designed to accommodate the mattresses’ full load and dimensions, with controlled flooding and refilling mechanisms for precise buoyancy adjustment. Additional features like edge frames and removable deck boards facilitated seamless rigging.
The mattresses were securely connected beneath the Scaff-float pontoons using 2000kg ratchet straps, ensuring the load was distributed evenly across the pontoon frame. WH Scott & Son Engineers organised and managed lifting and land-based transport services of the 27-meter-long water intake line, mattresses and ScaffFloat system.
· The intake line was assembled at the site
· Marine matts were lifted on to the pipe and secured with natural ropes and ratchet straps
· ScaffFloat pontoons were lifted on top of the assembled pipe and mats and secured with ratchet straps. This had to happen in time with the incoming tide
· After assembly, the barge used the high tide to transport the intake line to the installation location
· The outgoing tide was used to lower the assembled pipe and Marine Matt construction to the seabed
· Once located a team of divers disconnected the ratchet straps to release the floating barges from water intake
Innovation
This Advanced Marine Conservation and Research project represents both a novel approach and a significant improvement over existing systems. The innovative use of carbon-neutral Marine Crete for protective Marine Matts, coupled with the eco-friendly installation methodology using ScaffFloat’s recyclable pontoons depending on the tide to deploy the pipe to the sea floor, rather than large barges and cranes, sets new standards for sustainability in marine engineering. The integration of real-time observation technology with the PLUTO-2 system enhances public engagement and educational outreach, demonstrating a holistic approach that combines advanced engineering with environmental stewardship and community involvement. The collaborative team effort, incorporating expertise from Structural Evolution, ARC Marine, ScaffFloat, Seawide Services, and WH Scott & Son Engineers, along with the strategic sourcing of materials from within a 70-mile radius, further underscores the project's commitment to sustainable practices.
Collaboration and Sustainability
The collaborative efforts of Structural Evolution, ARC Marine, ScaffFloat, Seawide Services, WH Scott & Son Engineers and MDL Marinas ensured a sustainable and environmentally friendly design and installation methodology.[CK1] Structural Evolution worked closely with local suppliers, sourcing materials and services within a 70-mile radius, thereby reducing transportation emissions and supporting the regional economy. The support of Seawide Services professional dive team for precise installation further minimized ecological disruption, displaying a coordinated approach to sustainability.
