Work is set to start in September 2023 on a major £3m repair and maintenance project for Plymouth’s lock gates which form a key part of the city’s coastal defences, protecting hundreds of homes and businesses from flooding, and providing access to the marina and fish quays in the Sutton Harbour and Barbican area of the city.
The project is being managed by the Environment Agency, with funding from the UK Government, and will see the replacement of worn lock gate cills and other key maintenance items. Work will be carried out by leading UK construction and infrastructure services specialists Kier.
Sutton Harbour Company, which is the Statutory Harbour Authority, and which operates the lock, Plymouth Fisheries and Sutton Harbour Marina, has been working in close collaboration and partnership with the Environment Agency and Kier in planning for the project and how operations and access will be maintained in the harbour.
Following detailed consultation with harbour users, programming of the project has been significantly revised and the scheme will now be carried out in two phases, with the aim of minimising, wherever possible, disruption to the harbour’s fishing and leisure fleets.
• Work to the outer gates will take place between 4th September 2023 – 8th December 2023. However, there are no planned restrictions on the operation of the lock gates after 7th November 2023, while the remainder of the first phase works are completed.
• Work on the stoplog gate across the old harbour entrance is planned to take place between 13th November and 17th November, during this period the permissive footpath across the lock will be closed.
• Work to the inner gates will take place between 11th March 2024 – 17th June 2024, but as above there are no planned restrictions on the operation of the lock gates after 16th May 2024, while the remainder of the second phase works are completed.
• A detailed access timetable showing periods when access to the lock will be restricted has been published on the project’s dedicated website, www.lockgates.info. Mariners are being encouraged wherever possible to plan their trips around this timetable.
There will be some activity on the quay side for a week before each set of works start setting up welfare facilities and work compounds.
For the majority of the works the lock will still function on a tidal freeflow basis (generally up to three hours either side of high tide with more limited access during working hours), with a limited number of 24-hour closures clearly set out in the access timetable. Access will be maintained for pedestrians using the swing bridge across the lock.
Where necessary, mitigation measures are being put in place to support the continued operation of Plymouth’s fishing fleet and marina leisure users. These measures include pre-arranged back-up “emergency” alternative landing sites with truck access to the Fish Quay, and providing temporary emergency berthing arrangements for vessels arriving outside periods of lock access.
Documents detailing the mitigation measures have been circulated to harbour users and are available to download here.
Some preliminary dive surveys took place earlier in July prior to work starting in September but did not impact on the operation of the lock.
A Spokesman from the Environment Agency said: “We are pleased to be able to undertake this challenging project to repair the seals between the gates the bottom of the lock and to allow it to continue to provide flood defences for the 600 homes and businesses surrounding the harbour, as well as 24-hour access to the harbour for vessels to the fish quays and marina.
“We and our Framework Contractor Kier have been working closely with Sutton Harbour Company and with their customers and have developed a pragmatic programme of work to reduce the impact of the works as far as is practicable.
“Our contractor and our project team will continue to work with Sutton Harbour to make sure that up-to-date information is provided to the harbour users for the duration of the work.”
A spokesman from Sutton Harbour Company, said: “The tidal gates are a critical part of Plymouth’s coastal flood defences and we are pleased to see such a significant investment taking place in their repair and refurbishment to ensure the continuing effectiveness of the tidal barrage for another decade.
“Throughout the planning for this project, our overriding aim has been to maintain operations in the harbour to the maximum extent possible and minimise disruption for harbour users during these essential works.
“We have worked with the fishing community and berth holders and engaged expert independent consultants to develop mitigation plans to ensure the ongoing operation of the fishing industry and to meet the needs of leisure users.”
Updates will be provided via www.lockgates.info, social media and direct to harbour users, and via regular VHF broadcasts by the Lock Team to vessel skippers.