Trwyn Du Modernisation DAS & Heritage Statement

Off Trwyn Du Point, , Nr , , North , LL58 8RP November 2019 Context

Trinity House is the General Lighthouse Authority for , Wales, Gibraltar and the Channel Islands with duties as a statutory undertaker under the Merchant and Shipping Act 1995. Over its 500 year history, has built many of the of Wales, which it continues to maintain and operate today as part of a coherent mix of physical and digital aids to navigation.

As well as routine maintenance and ongoing monitoring, Trinity House lighthouses are reviewed every 20 years or so to ensure that they will continue to meet their navigational requirement, are efficient, do not rely on obsolete equipment, are safe to access and maintain etc. They are then re-engineered to ensure that they remain fit for purpose for the next 20 years or so. This is essential to ensure that they continue to have a future as modern aids to navigation.

Trwyn Du Lighthouse, a Grade II* listed Building is currently being reviewed as part of this process. Alterations are required that have been identified as affecting the historic character of the listed building. These being;

1. Access Arrangement Alterations 2. New Hazard Warning System 3. Replacement Solar Panel Assembly

Isle of Anglesey County Council’s informal advice in respect to those alterations has been sought in advance of this formal application for Listed Building consent. Heritage Context.

Trwyn Du is a Grade II* Listed Building, designated on 26/03/1999 (amended 17/07/2002). Its listing description reads;

History The lighthouse was built to mark the north entrance to Menai Strait, and the passage between the two islands, in 1835-38. It was designed by James Walker, consultant engineer to Trinity House. The llighthouse was manned until 1922 when it was automated and converted to gas power. It was converted to solar power in 1995 and solar panels fitted to the gallery. The gas power equipment remains on station.

Exterior Ashlar, painted in broad bands of black and white. A circular tower 96 feet high (29.26m), on a stepped base, stepped in height at the half-way point, and with crenellated parapet corbelled out; cast iron lantern with conical roof surmounted by ball finial carrying arrow weather vane. Doorway in lower stage above the stepped plinth with Trinity House arms in relief above it, and small windows aligned with it in upper stages, which also have other intermittant windows. All windows are small-paned sashes, the openings apparently originally triple glazed. Lantern has grid of glazing bars, obscured on the landward side. One fog warning bell is suspended from the parapet. 'No Passage Landward' in large painted letters facing to either end of the strait.

Interior Basement in the stepped plinth of the tower holds water tanks which were designed to receive rainwater gathered on the roof. Store room to ground floor, with shallow domed ceiling. Enclosed stone stair winding against the external walls. First upper level has former keeper's living room, wth built-in dresser, cast iron range (with enriched ironwork), pump and sink. Single rooms on each of the two levels above each retain small decorated cast-iron fireplaces. The original curved panelled doors remain throughout. Service room at top level below lantern has inscribed stone, 'Except the lord build the house....Psalm MCXXVII', and cast iron baluster to stairway to lantern. Fixed lens of first order catadioptric type, carried on a cast-iron platform which supports the braced cast-iron base of the optic.

Reason for designation A remarkably complete early C19 lighthouse, which is of particular note for the exceptional survival of many of its original internal fittings.

It is noted that none of the historic features referred to in the listing description are affected by the proposals outlined in the following sections of this statement with the exception of the fog warning bell. Existing Access/ Egress Arrangement

Access and egress requirements to/from Trwyn Du lighthouse may be at any time, on any tide. When the tide is all the way out, there is a short window of time when access may be on foot. The doorway is many meters above the inter- tidal sea bed and so a long climb is necessitated. Other than at this lowest point in the tidal cycle, access must be by boat and there must be a disembarkation of personnel, equipment and materials between boat and steps. In rough whether weather the disembarkation onto the steps is especially hazardous – not just because of risk of slipping/falling, but also because of the risk of boat movements crushing a person against the lighthouse.

As can be seen in the picture below, access then entails climbing a set of stone steps cut into the dressed stone of the lighthouse to the entrance door which is set well above high tide level. The steps are worn and uneven and due to tidal wash and absence of grip are slippery. There is only sufficient depth to the steps to allow the front part of the foot onto the step. Hand grips are rudimentary iron bronze clasps embedded into the stone. A safety harness can be clipped and unclipped to clasps as one ascends/decends the steps. From this precarious position at the top of the steps, one must attempt to open or close two weathered wooden doors before leaving the steps and entering the lighthouse. If aAccess is in windy conditions this can be- extremely perilous, even more so when the conditions are windy and wet. Transporting equipment and materials into the lighthouse adds further challenges.

Such an access arrangement may have been satisfactory in the 19th century when the lighthouse was built, but it is far from satisfactory in the 21st Century when the safety of personnel is paramount.

Access – the options and the proposed solution

The very best future for a historic lighthouse is for it to continue in its current and historic function – as an operational aid to navigation. To continue to remain practical for such use, lighthouses such as Trwyn Du have continuously adapted to changing requirements and improving technology – that is a key element of their historic character. In this case, meeting modern standards for safe access is essential. That said, Trinity House has endeavoured to minimise impact on the historic character of the building whilst meeting this essential requirement.

The following is proposed in order to improve the safety of the access;

1. Installation of new metal steps to external face of lighthouse. 2. Installation of a metal platform to allow safe opening of doorway

Fabricated steps will offer better grip and a better foot support. It will include a buffer, partially enclosing the user so as to provide protection from boat movements that might otherwise crush them. It will include harness clip provision to further enhance safety. Once at the top, the user will be able to access a safe platform from which the doors can be safely opened. Heavy items can be safely pulled up from boat to platform and then through level access into the lighthouse.

In designing a new safer access arrangement, considerable thought has been given as to how to minimise impact upon the historic character of the building. Key objectives in achieving this were identified as being

a. To retain existing fabric - the existing doors, the historic access steps and clasps unaltered b. To minimise visual impact upon the lighthouse.

To some degree a balance has had to be struck between ‘a’ and ‘b’ above. For example, the original idea was to remove the existing door and insert a new door further in so as to create an alcove. However as well as less functional than the chosen solution, this option had a greater effect on the historic fabric and so the external platform solution was selected in consultation with conservation officers.

The proposed solution allows the historic steps and clasps and the doorway to remain in place unaltered. There is to be no loss or significant intervention into historic fabric. The proposed additions can be entirely removed should circumstances change in the future, returning the historic lighthouse to its current appearance.

Whilst the new steps and platform will cause some harm to the appearance of the building, it will appear quite clearly as a modern addition with the historic form of the lighthouse maintaining its integrity. At high tides only the platform and a short stretch of the new steps will be visible.

The steps and platform are proposed in marine grade stainless steel - not only because this minimises maintenance in this difficult to access location, but because it is considered that this is an honest finish for such an unequivocally modern addition and is preferable to seeking to blend the works in with the historic building. However, Trinity House are open to discussing alternatives if there is a strong view to the contrary.

New Hazard Warning System

The 178kg Fog Warning Bell is mentioned in the Listing Description and is the only example of a fog warning bell on any Trinity House lighthouse. The author of this report has not established its precise date of installation, but it does not appear in lighthouse drawings of the late 1892, however a historic photo supplied by Daniel Sturridge at the following website; http://www.penmon.org/page6.htm (about half way down) suggests that its installation cannot have been too long after that. This photo shows that the bell was originally suspended below the gallery

The bell appears to have been moved to its current position in the gallery when the station was converted to gas/co2 in the late 1940s. Further modifications were done in 1960/66 and in 1995 / 1996, a new electric operating mechanism to work the bell was installed in conjunction with the solarisation of the station.

The bell is struck once every 30 seconds, 24 hours a day, 7 days a week. This is energy intensive – energy being particularly valuable in a solar station where there is a direct connection with the number of solar panels. The range of the bell’s chime is 0.5NM but it does not have the clarity of modern fog signal emitters. Furthermore, it is inconsistent with the sound of other fog signal emitters and it is advantageous to the mariner for the sound pattern to be consistent with other Trinity House fog warning. These are all being standardised to a 3 second tone every 30 seconds.

The bell (and more importantly its mechanism) being unique, it is difficult and costly to maintain. Because it is none standard, parts cannot be quickly sourced and must be especially made. This can take time – time when the fog warning may be out of action. For all these reasons, the bell is not considered to have future viability as an active aid to navigation. It is proposed to replace its function with a service standard Hazard Warning Signal on a small mounting below the existing navigation lights which are mounted on the gallery – as shown in the below diagram and photo-montage.

This new emitter will use much less power, as it will only sound in foggy conditions (rather than 24hrs a day as the current bell sounds), be recognisable to the mariner as a modern fog signal consistent with others, and will be easier and quicker to monitor, maintain, repair and replace.

It is proposed that the historic bell, no longer operational, is retained in its current position (minus the modern mechanism in the box that can be seen above the bell to the right of the lights in the photomontage).

In view of its small size, its colour (white – not red!), the presence of existing associated modern plant and the fully

reversible nature of the installation, this installation would have no material impact on the historic character of the

building.

Quite understandably, members of the public will miss the sound of a bell that has rung out so consistently for so many years, however adaptation to improved technology has always been part of a lighthouse’s lot and as discussed in earlier sections of this report the long-term survival of a lighthouse depends upon it. Replacement Solar Panel Assembly

Trwyn Du was solarised in 1995/1996. The light was moved from its historic position inside the lantern room (where the historic lens remains) and positioned outside on the gallery rails where it remains (see previous picture).

Solar panels to power the light and the bell mechanism (as well as other electrical requirements) were mounted onto a stainless steel frame fitted to the south (landward) side of the gallery outside the lantern room.

The solar panels do not impede the light as they sit within the blank arc where the light is not required to be seen and where the lantern room itself impedes the light in any case.

However, the existing arrangement entirely blocks off the gallery and makes it difficult and hazardous to access the existing solar frame arrangement for cleaning and maintenance and an alternative solution is sought.

Two alternative solutions were considered to resolve this problem;

a. Narrow profile solar panels on a frame could be fixed to the outside of the lantern room immediately in front of the astragals and glazing panels (in place of the existing ‘A’-frame). Whilst this solution would still ‘eat away’ at the limited space in the gallery walkway, the gallery would become just about passable.

b. Solar panels could be fitted within the astragals, in place of the glazing panels and blanking plates within the blank arc. A seal would be used to ensure the fitting is water-tight. This solution has the advantage of giving a much tidier appearance and of maximising the space in the gallery walkway.

From the inside, the panels would appear in large part like the blanking plates historically used in place of glazing panels within the sectors of the arc not required to be lit. They would be backed with a metal panel that could be painted black in keeping with the existing blanking plates. However there would of course be junction boxes on each panel as well as wiring to connect the system to the batteries.

Although both have advantages, following consultation with Anglesey Council’s Conservation Officer, it was decided that option ‘a’ was preferable because of its minimal intervention in the historic fabric.

The new solar array would simply replace the existing but would appear a little ‘tidier’. It is considered that on balance, this replacement presents minor improvement to the historic character of the building. Means of fixing have been devised to the gallery floor so as to avoid intervention in the more sensitive historic feature of the astragals (the framework holding in the glazing panels).

Planning Permission and Habitats Matters

The proposed works (in so far as they constitute ‘development’) have deemed planning permission under Schedule 2, Part 17, Class I to The Town and Country Planning (General Permitted Development) Order 1995. No advice is sought from Isle of Anglesey Council in respect to planning permission.

The lighthouse does not present habitat attractive to any protected species, although vagrants are always possible. In terms of designated habitat, Trinity House is a Competent Authority for the purposes of The Conservation of Habitats and Species Regulations 2010 (‘the habitat regs’) and a Section 28G Authority for the purposes of the Wildlife and Countryside Act. As such, we would carry out a Habitats Regs Assessment (HRA) and seek assent from Natural Resources Wales separate to the Listed Building application process.

Conclusion

The proposals have a positive or neutral impact upon the historic character of the listed building – with the exception of the proposed new access arrangements. This element of the proposal would result in some harm to the historic character of the building, however such harm is justified by the overwhelming public interest of ensuring safe access – as well as the heritage benefit to the lighthouse of improving its long-term viability. Best efforts have been made to secure a solution that meets this requirement whilst minimising impact on the historic character of the building.