Climate change connections

Hurst Castle, Hampshire following the collapse of part of its 19th century battery. (Photo: English Heritage).

Introduction

At first glance the formidable walls of hurst castle look the definition of immovable and solid, standing guard over the entry to the Solent for hundreds of years. However, in late February 2021 a section of the eastern battery suddenly fell into the sea. This collapse and the ongoing discussions around the site’s future management are emblematic of the issues posed by climate change to our heritage.

The castle’s position at the end of an exposed shingle spit has long made it vulnerable to the forces of the wind and waves. As well as changes in longshore drift, the fort now faces the increasing frequency and intensity of storm events and rising sea levels due to climate change. Holding the line in such a dynamic and highly volatile location requires considerable intervention and cost. Consequently, Hurst Castle is among the most challenging sites to be cared for by the English Heritage trust.

Built under Henry VIII and subsequently greatly enlarged in the 19th century when it formed a key fortress protecting one of the world’s most heavily defended areas, the castle played an active role through both world wars and remained in military use until 1956. Since arriving in the care of English Heritage there have been numerous investments to protect the building. In 2019 an extensive programme of works took place to stabilise the foundations of the west wing of the castle and to reinforce its sea defences. The charity underpinned the west wing’s foundations, replaced broken groynes and barriers, and replenished the beach with 7,500 tonnes of shingle. Since the collapse of part of the eastern battery in 2021, urgent work has seen an additional 22,000 tonnes of shingle and rock armour transported along the spit to protect the east wing. Specialist contractors were employed to undertake extensive geotechnical investigations around the castle and on the spit itself to help understand the structural integrity of the foundations and movement in the shingle. But it is clear there will be no quick fix. Estimates suggest that sea levels will rise in the area by one to 1.5 metres in the next hundred years, and each time a storm hits the spit, thousands of tonnes of shingle are washed away. Developing a long-term strategy for sites such as Hurst Castle presents a complex challenge and can only be addressed by drawing upon a wide range of expertise, learning from seminal work undertaken by the National Trust and Historic Environment Scotland, and by developing new partnerships.

Coastal connections

In 2022 Hurst Castle was included on the World Monuments Watch, a selection of 25 heritage sites of worldwide significance whose preservation is urgent and vital to the communities surrounding them. This list is collated by the World Monuments Fund, the nonprofit organisation that is devoted to safeguarding the world’s most treasured places. Now a new project called ‘Coastal Connections’ has been launched by English Heritage together with the World Monuments Fund. This initiative will establish a global network of coastal heritage sites for sharing best practice in meeting the challenges of climate change. Central to the project is knowledge-sharing; the creation of a series of online seminar discussions and a ‘virtual classroom’ to create digital resources for site managers and stakeholders. Through the project, those dealing first hand with these challenges, from caretakers of the striking medieval fortification of Methoni Castle in Greece to the communities around the trading posts of the Ghanaian coast, can work in partnership to develop the tools and principles to help guide future management decisions.

This approach is complemented by initiatives for engaging communities that are designed to strengthen the vital role that local people play in supporting, maintaining and, over time, in recording and remembering heritage. At Hurst Castle, for example, this involves working in partnership with the site manager, whose family has maintained the site for generations, and other local stakeholders. This will promote greater understanding of the ongoing – but not geographically unique – challenges facing Hurst Castle and other coastal heritage sites.

Building resilience

While coastal erosion may be the most visible impact of the changing climate at our sites, there are many other signs. English Heritage cares for the National Heritage Collection of over 400 buildings, monuments and places across England. Each year brings greater evidence of the impact, from an increase in heat damage to collections and a migration of pests, to erosion from driven rain and damage from water ingress. However, while the rate of change is accelerating, we are neither starting from scratch nor powerless to act. Our first Climate Action Plan, which was approved in June 2021, outlines targets to build climate resilience and sets out a pathway to raise awareness and reduce our own environmental impact.

Last year English Heritage joined with seven other major heritage bodies from across the UK to form the Heritage Adaptation Partnership with the aim of sharing expertise and progressing work on climate risk and adaptation response. This group has worked together to identify and collaborate on research, build on the National Trust-originated climate hazards map, and to explore decision-making thresholds on when to change site management in response to climate change.

At English Heritage we are using the climate hazards map and additional data to get an overview of risk across our sites. This involves identifying those that appear to rate highly for climate hazards, such as extreme heat, and then focusing on five sites to undertake detailed climate risk assessments, drawing in locally observed changes from staff and volunteers. This work, in partnership with the Benefact Group, will allow us to sense-check the climate data, refining our understanding of complex interrelationships on site and the different impacts being seen across buildings, collections, landscapes and operations to enable climate informed decision making and more effective adaptation.

Looking to the future

The future may sometimes look bleak. However, our historic sites are no strangers to change and together we can address these challenges by respecting and learning from different approaches to adaptation, mitigation and loss; sharing expertise gained by intervention in local contexts around the globe; and engaging local communities through open, honest and inclusive communication. By learning from what is done elsewhere we can share new perspectives and discover insights that lead to greater wisdom in how we manage heritage more sustainably. In addressing the impacts of climate change, a local site can have global significance, not just in terms of its heritage value but in terms of how we can learn to recognise, understand and adapt to the challenges we face.

This article originally appeared as in the Institute of Historic Building Conservation’s (IHBC’s) Yearbook 2023. It was written by Ruth Knight, Head of Climate and Sustainability at English Heritage and Dr Alex Kent, Coastal Connections Project Lead, English Heritage and World Monuments Fund.

--Institute of Historic Building Conservation

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