SCREENING FOR NATURAL HAZARDS TO INFORM A CLIMATE CHANGE RISK ASSESSMENT OF THE PROPERTIES IN CARE OF HISTORIC ENVIRONMENT SCOTLAND INTRODUCTION PURPOSE AND SCOPE ADHBHAR IS LEUDACHD This document presents the to develop best practice and the impact of climate change results of an initial baseline integrate climate change actions on their areas of responsibility assessment of natural hazard into its operations, in line with and their daily operations, and risk to inform a Climate Change the Public Bodies Duties under build resilience. The Scottish Risk Assessment of Historic the Climate Change (Scotland) Climate Change Adaptation Environment Scotland’s (HES’s) Act 2009 and Climate Ready Programme specifically tasks Properties in Care. It uses a Scotland: Scottish Climate HES with quantifying heritage number of existing natural hazard Change Adaptation Programme. assets affected by climate datasets, which determine the change using GIS and creating risk of damage and loss to sites, The Climate Change (Scotland) a climate change risk register as indicators of susceptibility Act 2009 (the Act) places for the Properties in Care. These to climate change. The report duties on public bodies to formal obligations are reflected outlines the drivers behind contribute to emission reduction in the actions set out in our own carrying out the study as well targets, deliver programmes for Corporate Plan (2016), For All as the basic methodology of adaptation, to increase resilience, Our Futures, and our Climate the assessment itself. This study and to act in a sustainable way. Change Action Plan (2012-2017). represents the first step in a HES is identified as a ‘Major comprehensive and ongoing Player’ under the Act, due to exercise to understand, monitor its size and influence. Guidance and manage environmental risk on these duties published in to the HES Estate. This study 2011 makes it clear that public is part of HES’s ongoing work bodies are expected to assess Front Cover: Brough of Birsay Broch of Gurness 2 A Climate Change Risk Assessment CONTRIBUTORS DATA LICENSES This report was prepared by the Historic Environment © All images Crown Copyright HES or Scotland Climate Change Team with contributions Historic Environment Scotland, except from Emily Tracey (British Geological Survey). map images, where copyright is as follows: Principal authors: David Harkin, Dr Mairi Davies and Dr Ewan Hyslop (Historic Environment Scotland). Contains Historic Environment Scotland and Ordnance Survey Data © Historic ACKNOWLEDGEMENTS Environment Scotland © Crown copyright This project has benefited from partnership and database rights 2017 Ordnance Survey working with British Geological Survey and Scottish [100057073] Ordnance Survey Data. Environment Protection Agency. Particular thanks are due to Dr Fiona McLay of SEPA for facilitating Materials derived from the British data access. Geological Survey's work included in this publication are reproduced with the We are grateful for the invaluable advice and support permission of BGS. Copyright Natural we received during this project from Adaptation Environment Research Council (NERC). Scotland, particularly Dr Joseph Hagg, Science All rights reserved. and Skills Manager. The project benefited from discussions with our colleagues in the Adaptation © 2017 Scottish Environment Protection Learning Exchange Risk Task Group. Agency. Some features of this map are based on digital spatial data licensed from CONTACT INFORMATION the Centre for Ecology and Hydrology, For more information please get in touch with us © CEH. Includes material based upon by emailing [email protected] or phoning Ordnance Survey mapping with permission 0131 668 8600. of H.M. Stationery Office, © Crown Copyright. Licence number 100016991. 3 PREFACE RO-BHRIATHAR Scotland’s climate is changing at project, on natural hazard risk. to the risks identified within an unprecedented rate. The last This represents the first steps in our PIC boundaries, and do not century has been characterised the development of: (i) a current consider risks that may occur by a continuous increase in climate risk register for the HES just beyond these boundaries. temperatures, altering patterns Estate, and (ii) a methodology for The impacts on staff and visitor of precipitation and increased assessing the impacts of climate safety, internal collections, site frequency of unpredictable and change on heritage assets in operations and access are outside extreme weather events. Since the the wider historic environment. the scope of this work. However, early 1960s, annual precipitation In partnership with the British these may form the basis of future levels have increased by over 20%; Geological Survey (BGS) and phases of the ongoing project. it is now 1°C warmer, the growing the Scottish Environment season has been extended by over Protection Agency (SEPA), we Initial analysis of the results has a month and sea levels continue have conducted a desk-based, indicated that out of the 352 to rise at over 3mm a year (Sniffer Geographic Information Systems 'sites' investigated, 89% are 2014). This has implications (GIS) analysis of natural hazard exposed to high, or very high for the historic environment. risk to the 336 Properties in Care levels of risk (some of our 336 Changing climatic conditions (PICs) of Historic Environment PICs have more than one area can alter and accelerate decay Scotland. By overlaying spatial of ‘guardianship’ or ‘ownership’, processes of historic monuments data pertaining to our own PICs meaning we ran the assessment and archaeological sites. Historic with natural hazard data sets, for 352 ‘sites’). When we then buildings that have survived supplied by the BGS and SEPA, consider the mitigating factors well in the past and in current we have been able to conduct the and controls already in place, climatic conditions may become most thorough baseline analysis such as routine maintenance less able to cope with changing of natural hazard risk carried and ongoing conservation work, weather patterns caused out to date on the HES Estate. the number of sites classified as by climate change (Historic This has allowed us to identify ‘at risk’ is reduced to 53%. With Environment Scotland 2016). the properties we now believe this new information, we can To better understand the impacts to be most at risk from climate now conduct a more in-depth of current climate threats change. At this stage, we have analysis of climate change risk at to the Historic Environment focused on the impacts to the these high-risk sites identified in Scotland (HES) Estate, we have physical fabric and cultural the baseline study. For our own undertaken a Climate Change significance of the properties requirements, this evaluation of Risk Assessment (CCRA) focusing themselves. As such the results climate change risk will provide initially, for the purpose of this of this report are strictly limited improved evidence-based 4 A Climate Change Risk Assessment decision-making in order to better results of the assessment are risks to these in more detail and prioritise ongoing investment then presented, including a explaining site-specific mitigants through our conservation and breakdown of the risk posed by and controls. The Threave Castle maintenance programmes, thus the six different natural hazards case study demonstrates a site ensuring the long-term survival considered in this study; those that was designed with flooding of the properties in our care. being flooding (fluvial, pluvial, in mind. The Blackness and This report outlines the policy groundwater and coastal), slope Fort George case studies give context and drivers behind instability and coastal erosion. examples of sites at high risk from our assessment, including the These are supplemented by natural hazards where we have statutory duties placed on us as tables, charts, graphs and images intervened to mitigate against a public body. The report then to explain the nature of hazards, these risks. Finally, the Kilchurn details the basic methodology illustrate the data analysis and Castle case study provides an which has been developed for highlight the unique nature of the example of a site that has an the assessment, likely to be the sites in our care. The report also inherent resilience to changing first of its kind for a heritage- provides case studies of four sites, environmental conditions of the focused organisation. The baseline exploring the specific hazards and landscape in which it is situated. Dundrennan Abbey 5 The location of Historic Environment Scotland’s Properties in Care. 6 A Climate Change Risk Assessment CONTENTS CLÀR-INNSE PURPOSE AND SCOPE 2 3. RESULTS 26 PREFACE 4 3.1 Data Limitations 27 CONTENTS 73.2 Fluvial Flooding 28 FIGURES 8 3.3 Pluvial Flooding 29 TABLES 9 3.4 Coastal Flooding and Coastal Erosion 30 DOCUMENTS REFERRED TO IN THE TEXT 10 3.5 Groundwater Flooding 32 GLOSSARY 11 3.6 Slope Instability 33 3.7 Sites at Risk 34 1. INTRODUCTION 12 1.1 Aims and Objectives 14 4. FUTURE RISK 35 1.2 The Risk Assessment and Partnership Working 14 4.1 Climate Change in Scotland 35 1.3 Why Focus on Natural Hazards? 15 4.2 Impacts on the Historic Environment 37 1.4 Outputs and Use of the CCRA 15 5. NEXT STEPS 42 2. METHODOLOGY 16 6. CONCLUSION 43 2.1 Overview 16 7. REFERENCES AND FURTHER READING 44 2.2 Datasets Sources and Information 17 2.3 Calculating Risk Scores 18 THREAVE CASTLE 45 2.3.1 Generating and Assigning Likelihood Scores 19 BLACKNESS CASTLE 49 2.3.2 Generating and Assigning Impact Scores