A complex repair and reconstruction project is continuing on the 169-year-old Plover Scar lighthouse in the Lune estuary.
The lighthouse off the north Lancashire coast (near Cockersand Abbey) was hit at night time by a large, empty, cargo vessel en route to Glasson Dock in March last year.
Substantial damage was caused by the impact. The upper section of stone wall was nudged a third of a metre off-centre and metal strengthening bands around the lighthouse snapped.
The impact also left a gap in the stonework which, in rough seas and high tides, would have meant more stones being dislodged - further threatening the stability of the structure.
An engineering inspection recommended the only method of repair to be the dismantling and rebuilding of a substantial part of the upper part of the structure - an exercise complicated both by the movement of tides and the need for approvals from environmental regulatory bodies and the procurement of a Marine Licence.
Another issue which had to be considered was whether the work should be done using a spud barge (a specialised type of flat decked boat with legs, used for marine construction operations) or onshore. The latter option was chosen.
The lighthouse is owned and maintained by Lancaster Port Commission, based at Glasson Dock.
Its website reports: “The project is taking longer than originally anticipated for two reasons. Firstly, due to the length of time it took to obtain the necessary licences and permissions, the contractors lost a considerable length of time when they could have been working during two low-tide periods per day in daylight, rather than the one they are now restricted to.
“Secondly, our only view into the internal structure before work began was through a hole created at the impact site.
From this view, it had been assessed that the centre of the structure was loose stone rubble fill.
This has turned out not to be the case, as the stone rubble was actually set in concrete, which has had to be jack-hammered loose before removal.
All this fill material has had to be hand-shovelled into tote bags, which have then been lifted by crane on to the seabed, awaiting re-use as the structure is rebuilt.”
The lighthouse has been shrouded in scaffolding for the past few months, giving contractor MPM North West Ltd of Maryport the opportunity to carry out work when the tide is out.
Last October a crane carefully lifted off the cast iron lantern from the “top” of the lighthouse. The lantern was taken by trailer to Maryport for restoration work.
It did not contain any old lighting gear, prism lenses, etc.. Equipment of that nature was vandalised many years ago, and the lighthouse has used battery/solar-powered lighting in more recent years.
Similar lighting, to maintain the statutory requirement for a lit navigational aid for shipping in the estuary, is currently attached to the temporary scaffolding.
Lancaster Port Commission says 229 stones have been removed from the structure, each of the stones being individually numbered before being lifted off.
They have been laid out on the beach and dressed ready for re-use. The onshore work has been carried out in a specially-created compound on the car park overlooking the estuary as well as on the beach.
A suggestion from one quarter, at an early stage of the post-impact discussions, was that the damaged lighthouse be completely dismantled and permanently removed and replaced with a simple, concrete tower with a navigation light on top.
That idea was firmly rejected by Lancaster Port Commission, which was determined to see the iconic structure restored to its pre-impact condition.
One interesting historic point discovered during pre-work research, and proved during the dismantling works, is that an extra casing of stones was added to the lower section wall nine years after the lighthouse was constructed in 1847. This extra stone casing actually formed the lower walkway.
No definite date for completion of the current work has been announced, but Lancaster Port Commission is hoping it will be within the next two months.
The likely costs involved in the repair and reconstruction project have not yet been made public as legal and insurance issues have yet to be fully resolved.
* Thanks to Helen Loxam, CEO of Lancaster Port Commission, for assistance with this article, which originally appeared in the February 2017 issue of the Lancashire Local History Federation newsletter.
* For more information about the ongoing work at Plover Scar lighthouse visit www.lancasterport.org/news