Geo-conservation

Appreciating, conserving and promoting Somerset’s diverse geology

 
Desiccation cracks on bedding planes in the Devonian Hangman Sandstone. (Photo: courtesy Somerset Environmental Records Centre)

Geo-conservation

In Somerset there are two different designations which provide for geological conservation: Local Geological Sites (LGS) that may be of local to regional importance (with which SGG is involved); and Sites of Special Scientific Interest (SSSIs) overseen by Natural England, that are recognized as being of national importance for the earth sciences.

Beyond these specific designations, there are however many other geological exposures and geomorphological features that help to provide an understanding of the varied landscapes of Somerset. We have (until recently – see our News page for August 2024) no internationally recognized geological conservation sites in the county (such as the nearby UNESCO Jurassic Coast World Heritage Site in Dorset/east Devon or the UNESCO Riviera Geo-park in south Devon), but we think that many aspects of Somerset’s geology are just as interesting and worthy of conservation!

 

Local Geological Sites

Please note that LGS designation does not imply any right of public access and many LGS are on privately owned land. 

The main focus of our Somerset Geology Group (SGG) activity between 2016 – 2022 has been working in partnership with Somerset Environmental Records Centre (SERC) to carry out a major review of Somerset’s existing LGS (including those for the Devon part of the Exmoor National Park). LGS were formerly known as Regionally Important Geological Sites (RIGS). Those in Somerset were originally mostly identified during the late 1980s and 1990s and then adopted in local plans.

The LGS review project has been steered by an LGS review Steering Group, with reconfirmation and any adjustment to boundaries overseen by an LGS Panel. See SERC’s LGS page for further details, including: the key questions we have used in Somerset to assess the sites against the four national criteria for LGS; the final report on the project; and the five area reports that summarize the overall conservation interest for that part of Somerset to which the individual LGS contribute (the area reports are also available below).

SERC is the lead organization in Somerset for the Local Sites Partnership (which also includes Local Wildlife Sites), with SGG being one of its associated specialist groups. There are currently 220 LGS in Somerset and SERC now holds an improved evidence base for each LGS, with details now having been sent to many more of their landowners.

Planning – Designation of LGS is covered in the Government’s latest National Planning Policy Framework (NPPF) for development control (see paras 180, 181 and 185) and in the earlier more detailed DEFRA 2006 Local Sites: Guidance on their Identification, Selection and Management, where the relevant criteria for LGS designation are set out.

The Somerset Council web site provides a link to the currently adopted local plans in Somerset – the policies of which still stand until the council produces a new Somerset-wide local plan. These local plans all cover LGS in some way – but may differ in their wording. Additionally, some of the LGS are in Exmoor National Park – its adopted local plan is available via its planning page  here.

Development – Developers and their agents therefore need to consider how any development requiring planning permission would affect an LGS to ensure that the interest is conserved. See the SERC web site for how to request a search of SERC data for any information held to assist with this. NB Bone fide geological enquirers interested in, for example, information for research and/or potential field study use relating to LGS, should contact SERC direct initially (and SGG may also be able to assist).

Information for owners – Otherwise LGS designation relies entirely upon sympathetic management by owners for any conservation management that might ideally be needed. Unlike SSSIs, designation does not imply any legal or statutory duties. If you own or manage a Local Geological Site, and would like to gain a greater understanding of the interest and/or discuss potential conservation management, please contact SERC – and our team of SGG-sourced SERC volunteers may be able to assist. We have also produced an introductory leaflet on LGS for owners which is available as a PDF here.

Future LGS activity – We agreed in 2023, after completion of the review, to continue our working arrangements with SERC, including the LGS Panel and a small team of SGG-sourced SERC volunteers, for any ongoing LGS-related activity. However, SERC is tightly resourced and our capacity relies on voluntary input, so at present we envisage further work in the coming years on LGS will be quite modest.

Our agreed priority is now to build relationships with owners/managers of existing LGS to help them understand the interest of their LGS (especially where owners can be newly identified and contacted for the first time; or where there is scope for conservation work and/or interpretation). 

 

LGS area reports

The five area reports from our LGS review partnership project provide an overview of the LGS for the main landscape areas of Somerset. They include some wider context compiled to assist with reviewing the LGS, but they are not full geo-diversity audits or action plans. They include, for example, some context on: the main stratigraphical periods and formations occurring in each of these areas (with some equivalent older names); nationally designated Geological Conservation Review (GCR) sites (all earth science SSSIs); and many suggestions for potential future community projects and interpretation. We therefore repeat these area reports below as well as them being available on SERC’s LGS web page.

 

 

More detail on LGS review – Further detail on the LGS review can be found in our SGG Updates between 2017 and 2022, with the spring number each year incorporating an annual progress report on the LGS review project, with the final report in the May 2022Update and on-going activity in later Updates. Two papers on the LGS review, written by our SGG co-coordinator, Garry Dawson, have also been published by he Somerset Archaeological and Natural History Society (SANHS):

Dawson G.J. 2022. Review of Somerset’s Local Geological Sites. Somerset Archaeological and Natural History Society. Proceedings Volume 166. Pages 248-252.

Dawson G.J. 2018. A review of Local Geological Sites in Somerset. Somerset Archaeological and Natural History Society. Proceedings Volume 162. Pages 126-129.  (the last three pages of this pdf link)

 

Earth science SSSIs

Please note that SSSI designation does not imply any right of public access and many SSSIs are on privately owned land.

In addition to LGS, a total of c 62 nationally important geological sites in Somerset have been identified through the Geological Conservation Review (GCR). They are either designated by Natural England as Sites of Special Scientific Interest (SSSIs) in their own right, or they may be within other wider SSSIs of biological interest. See JNCC for further background on the GCR nationally, including its database of sites, the conservation or ‘block’ categories used and publications.

Natural England‘s designations page provides a start point for information on SSSIs and links with DEFRA’s map of designations. NB The SSSI maps do not distinguish between earth science and biological SSSIs and SSSI citation statements do not necessarily refer to any GCR sites within them (which can be differently named) nor to the greater geological detail that may be available in GCR publications. Our LGS review area reports (see above) may assist to some degree in understanding the situation in Somerset as they include some context on these nationally important sites that was compiled to assist with the LGS review. 

 

Practical conservation

SGG may be able, via SERC, to advise on any practical conservation work desirable on LGS, and in some cases our members may be able to help directly to advise, arrange and/or carry out such work via their membership of groups that have the appropriate insurance, etc.

For example, we have been able to facilitate clearance of vegetation from LGS rock faces at:

  • Clatworthy Reservoir for Wessex Water in 2017 via the Open University Geological Society and Milverton Conservation Volunteers. See link to Dawson, 2018 above. The article includes before and after photos of the clearance of an exposure of the Devonian Morte Slates.
  • Great Wood in the Quantocks for Forestry England in 2021/22 via the Quantock Countryside Volunteers. See link to Dawson, 2022, above. The article includes before and after photos of the clearance of an exposure of the Devonian Hangman Sandstone Formation.
  • The A37 south of Yeovil for Somerset Highways in 2023/24 via our equivalent group in Dorset, DIGS. See photo story below.

“Before and after” photos of clearance work on the LGS on the side of the A37 Dorchester Road (just south of Yeovil) carried out in 2023/2024 in conjunction with Somerset Highways to make visible the sandstone of the Lower Jurassic Bridport Sands Formation there, with its planar bedding, concretions and gentle southerly dip. The length of the section means that lateral variation can be studied. Access is possible via a roadside footpath with grass verge, but this is a busy road with verge maintenance work from time to time. Please contact Somerset Highways if you are considering any field studies visit.

Local Building Stone

More detail can be found at:

 

Historic England, 2023:The Building Stones of England: Somerset and Exmoor (based on original research and text by Andy King, Geckoella Ltd and first published by English Heritage in 2011) is available as a pdf at https://historicengland.org.uk/advice/technical-advice/buildings/building-stones-england/ within a section of Historic England’s web site where the context of its wider work on building stones is described. It is one of a series of guides for each English county, that draw on research with the British Geological Survey, geologists and building historians, undertaken to compile its Building Stones of England Database – which provides more detailed information.

 

Orbach, J. 2015. The Buildings of England. Somerset: South and West (Pevsner Architectural Guides). Yale University Press includes an introduction to the building stones of the area written by the late Prof Desmond Donovan and the late Hugh Prudden.

 

Garry Dawson is currently leading a project in Somerset, in conjunction with South West Heritage Trust, to document the building stones used in Somerset’s towns and villages. See https://swheritage.org.uk/historic-environment-service/built-heritage/traditional-building-stone-research/ . A map with pie diagrams shows the percentage of buildings with different stone in each Somerset village – with work currently underway to provide more complete coverage of the county.  See also:

 

Churches – The information at https://swheritage.org.uk/historic-environment-service/built-heritage/traditional-building-stone-research/  includes Hugh Prudden’s 2006 Table of Building Stones in Somerset Churches, with some new data from the current project added by Garry. Hugh Prudden surveyed 336 Churches in Somerset during his lifetime.

 

Mike Barr’s 2019: Inventory of the Building Stones of Devon and adjacent parts of Dorset and Somerset, Volumes I and II, which are available as pdfs and include information on Somerset’s building stones. See also his paper:

 

The data collected by Mike for this inventory is also available, on request, from the Devon Heritage Centre:  Barr, M.W.C. 2023. Database of Devon and Somerset Building Materials. Devon Archives and Local Studies. Reference Number: ZBJM. Accession Number: D2023/233. 

 

Geo-conservation nationally

Earth Heritage Magazine – see https://www.earthheritage.org.uk  for a twice-yearly e-magazine produced by Natural England and partners. The back issues include many case studies of geo-conservation and interpretation projects from across the country.

Geoconservation: principles and practice was published by Natural England in 2023 (NE802). It focuses on the earth science SSSIs, with case studies covering different types of conservation interest and approaches to management – but has potential to help inspire and provide practical ideas for LGS as well. Available to download in three parts at https://publications.naturalengland.org.uk/publication/6152405931261952  

 
 
Page last revised April 2025.

 

Roadside, Flint Nodules