Port of Jersey’s Elizabeth Marina Facility
Ports of Jersey’s Elizabeth Marina facility has capacity for over 500 leisure boats. The marina is tidal with access possible for approximately for 3 hours at either side of high tide. The marina level is maintained by a hydraulically operated Tide Gate outside of this period. During inclement weather, there is a hydraulically operated Storm Gate which can be operated to protect the marina when required. When either, or both gates are operated, they are locked into place with hydraulically operated
locking pins. These gates are critical for maintaining the impounded marina (pond) level and for providing storm and surge protection.
Project Overview
Fairfield was appointed under an NEC contract, to review the existing hydraulic system in order to extend the life of the asset and to incorporate resilience measures in order to improve system reliability, maintainability and reduction in single point failure possibilities. We have worked with the client in developing their outline technical requirements, through specification and detailed design to final implementation.
Working directly with our client we have been able to design solutions to their operational and maintenance issues to provide a more resilient and purposeful system future proofing the asset. Given the hydraulic nature of the actuation, hydraulic systems pass across the marina mouth. Prior to the improvements being made there were common elements to the hydraulic system which meant that should there be an external leak or hose burst for example, the harbour personnel were required to climb down to access the cylinders in order to isolate them so that the tidal or storm gate could then continue to operate. The storm gate is vital to provide emergency storm protection. The changes have included the re-design of the hydraulic circuit, and solid external pipework to provide resilience in the pipe system. This also duplicates the cylinder functions and provision of isolation and facilitates the provision of changeover valves for use under fault or maintenance conditions. These changes have greatly improved the maintainability and resilience of the system, all being completed from a position of greater safety.
Hydraulically operated latches were previously employed to lock both the tidal and storm gates in their raised positions. These hydraulically operated latches have been replaced in their entirety with new electromechanically operated actuators and associated supporting steelwork. These measures have again greatly improved the maintainability and resilience of the system. They do this by reducing reliance on the hydraulic system, which passes under the structure and incorporating a manual
actuation system this leads to an increase in system availability.
Scope of Works
The overall scope comprised:
- Design, supply and implementation of hydraulic system modifications
- Design, flow calculations, supply and implementation of new stainless steel hydraulic pipework routes replacing the existing flexible hoses
- Design, supply and implementation of temporary works required to replace tidal gate main operating cylinder
- Supply and installation of new tidal gate hydraulic operating cylinder
- Refurbishment of built in parts such as trunnions
- Design of pedestrian walk-over covers for the new hydraulic pipework
- Design, supply and installation of 4 replacement latching electro-mechanical actuators and associated supporting steelwork for both storm and tidal gates
- All associated civils works including new troughs and ducts for pipework
- System re-commissioning, training and handover to client
KEY DELIVERABLES & SUCCESSES
The key success of the project was developing a number of measures to improve the system operability, reliance and availability from that which was previously provided. Understanding the operation of the gates, existing issues and nuances through engagement with the client team, we were able to identify the works areas which provided greatest benefit. In developing these changes, the system will be far more environmentally friendly. It also increases safety to operators and maintenance staff, and gives multiple levels of protection to ensure these critical assets remain available when needed most.