Cornwall Beach & Dune Management Plans · Beach Management Strategy produced by Halcrow in 2009. 2....

I n t e r im Repo r t : Po r thco than

Cornwall Beach & Dune Management Plans

Prepared for Cornwall Council

18 August 2016

Ash House

Falcon Road Sowton Exeter Devon

EX2 7LB

III

Contents Section Page

1 Introduction ............................................................................................................................ 1 1.1 Background ......................................................................................................................... 1 1.2 Project aim, objectives and approach ................................................................................ 1 1.3 About this document .......................................................................................................... 2

2 Site Visit Report ....................................................................................................................... 4 2.1 Attendees ............................................................................................................................ 4 2.2 Site Visit Record .................................................................................................................. 4

2.2.1 Background ............................................................................................................ 4 2.2.2 Issues ...................................................................................................................... 5 2.2.3 Other notes ............................................................................................................ 6

2.3 Photos ................................................................................................................................. 6

3 Environmental Characteristics ............................................................................................... 12 3.1 Introduction ...................................................................................................................... 12 3.2 Methodology ..................................................................................................................... 12

3.2.1 Designated Nature Conservation sites and Protected Habitats .......................... 12 3.2.2 Habitats and Species ............................................................................................ 13 3.2.3 Heritage Designations .......................................................................................... 13 3.2.4 Landscape Designations ....................................................................................... 13

3.3 Environmental Setting ...................................................................................................... 13 3.4 Ecology .............................................................................................................................. 14

3.4.1 Designated Nature Conservation Sites ................................................................ 14 3.4.2 Biodiversity Action Plan (BAP) Habitats and Species ........................................... 17

3.5 Designated Geological Conservation Sites ....................................................................... 18 3.6 Archaeology and Cultural Heritage ................................................................................... 18

3.6.1 Landscape Setting ................................................................................................ 18 3.6.2 Archaeology and Cultural Heritage ...................................................................... 18

3.7 Anthropogenic Pressures .................................................................................................. 18

4 Coastal Processes Understanding ........................................................................................... 19 4.1 Introduction ...................................................................................................................... 19 4.2 Shoreline Processes Overview .......................................................................................... 19

4.2.1 Key Characteristics of the Coastline Today .......................................................... 19 4.2.2 Forcing Factors ..................................................................................................... 23 4.2.3 Sediment Dynamics ............................................................................................. 27 4.2.4 Historical Shoreline Change ................................................................................. 28

4.3 Shoreline and Beach Profile Analysis ................................................................................ 31 4.4 Future Shoreline Evolution ............................................................................................... 33 4.5 Summary ........................................................................................................................... 34

5 Dune Inventory Site Summary ............................................................................................... 35

6 Future Beach & Dune Management Recommendations ......................................................... 37

7 References ............................................................................................................................. 39

SECTION 1 INTRODUCTION

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1 Introduction 1.1 Background Many of the sand dunes and beaches around Cornwall’s coast have recently experienced erosion and sediment loss. This is a pressing concern as these sand dunes and their associated sandy beaches are one of the most important natural amenities in Cornwall due to:

1. Their role in providing protection against the risk of coastal flooding due to the dynamic nature of beach‐dune interactions and their sheer size preventing the sea from impacting upon the hinterland behind the dune systems.

2. Their role in providing important biologically diverse habitats that cannot be easily recreated elsewhere if it were to be lost to coastal erosion or inappropriate development.

3. Their role in providing access to the sea for residents and visitors alike, which is vital to the holiday industry upon which a significant proportion of Cornwall’s economy depends.

It is vital therefore that the sand dunes and beaches around Cornwall’s coast, that represent some 15% of the total sand dune habitat in Britain, are managed in a holistic, sustainable way over the long‐term that balances the needs of each of the three distinct functions of sand dunes and beaches that combined make up the beach‐dune system, as illustrated in Figure 1.1.

Figure 1.1 The interaction of beach systems that compose the ‘beach environment’ and which must be considered together to provide a holistic approach to beach management (after James, 2000 in Frampton, A.P.R. (2010). “A review of amenity beach management”. Journal of Coastal research, 26(6), 1112‐1122, November 2010).

The approach to managing the beaches and sand dunes was investigated in between 2006 and 2009 by Halcrow on behalf of the Cornwall and Isles of Scilly Coastal Group, and led to the production of the Cornwall Sand Dune and Beach Management Strategy (Halcrow, 2009a). The main focus of the strategy is the management of flood and coastal erosion, although the habitat and tourism value of the dunes will also be considered. This 2009 project delivered an Inventory of Beaches and Dunes; a Best Practice Management Guide and two pilot Beach and Dune Management Plans (BDMPs) for Harvey’s Towans and Fistral Beach. It is this 2009 work that this current project is building upon to develop seven new BDMPs and review the two pilot BDMPs (see Section 1.2).

1.2 Project aim, objectives and approach The purpose of the project is to develop seven new long‐term strategic BDMPs for Constantine Bay, Porthcothan, Porthtowan, Summerleaze, Par Sands, Widemouth Bay and Praa Sands; and review and


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update the two pilot BDMPs produced in 2009 for Fistral Beach and Harvey’s Towans. This will be achieved by:

1. Identifying the best management approach; in terms of monitoring and intervention (when trigger levels are reached) requirements for beach and dune systems at each individual site, based upon the best practice framework developed as part of the Cornwall Sand Dune and Beach Management Strategy produced by Halcrow in 2009.

2. Providing a long‐term (50 year) approach to each site that is based upon an up‐to‐date understanding of the beach‐dune system and coastal processes at each site, as well as predictions of future coastal evolution.

The locations of these nine sites is shown in Figure 1.2.

Figure 1.2 Map showing location of the nine BDMP locations.

Development of the BDMPs will engagement with local community stakeholders and statutory stakeholders to seek local knowledge and guide selection of preferred management options. This report provides an interim report summarising the understanding of

1.3 About this document This interim report provides the findings of work to develop an understanding of the environmental characteristics, coastal processes and issues affecting the Porthcothan BDMP location (see Figure 1.3) and identifies a recommended approach to future management. Specifically, it:

Reports the findings of a site visit made on 12th May 2016 by members of CH2M’s project team and invited stakeholders (Section 2);

Provides details of the environmental characteristics of the BDMP area (Section 3);

Describes the coastal processes and recent shoreline evolution of the beach and dune system in the area (Section 4);


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Summarises the information from Sections 2, 3 and 4 into a revised dune inventory record for the site, updating the dune inventory record produced as part of the 2009 Cornwall Dune and Beach Management Strategy (Halcrow, 2009b) (Section 5).

Identifies the recommended future management approach to be incorporated in the final BDMP for Porthcothan, based upon the understanding of the environmental characteristics, coastal processes and issues (Section 6). These are to be confirmed in consultation with stakeholders and Cornwall Council. Once confirmed, they will be used to develop the BDMP document.

Figure 1.3 Map showing the Porthcothan BDMP location and extent (red outline).

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2 Site Visit Report On 12th May 2016, two members of CH2M’s project team visited the Porthcothan BDMP site to capture information about the site and take ground‐level photos. During the site visit, client representatives, stakeholders and local community groups were given the opportunity to attend, meet with the project team, discuss their aims and objectives for the site, and raise any issues and concerns. Information collected during the site visit will be considered when developing later stages of the project, including:

Stage 1 – Baseline Understanding (refer to Sections 3, 4 and 5 of this report)

Stage 2 – Define Issues and Objectives (refer to Section 6 of this report); and

Stage 3 – Develop Future Management Options.

The site visit report is presented within this section and provides:

a list of attendees (Section 2.1);

a record of the site visit including both factual information, comment and opinion provided stakeholders (Section 2.2);

a selection of photographs taken during the site visit to highlight salient points (Section 2.3).

2.1 Attendees Name Organisation / Interest

Sam Box CH2M

Emily Hewitt CH2M

Martin Clemo Cornwall Council

Jolyon Sharpe Cornwall Council

Scott Perry Provelio

Tim Neale Resident

Mary Neale Resident

Grace Strongman Resident

Arthur Marriott Resident

Richard Pearce Resident

Joyce Froome Resident

Kim Hayward Chair, St Eval Parish Council

Jim Coastworth Resident

Jane Darke Resident

2.2 Site Visit Record 2.2.1 Background The dune system seaward of the road formed after the war when fences were placed at the back of the beach. Sand accumulated and the dunes have grown considerably over recent decades, more than doubling in height over the last twenty years. Photographic (Appendix A) and anecdotal evidence suggests that the dune system continues landward of the road and that the houses built before the war along the road formed a barrier to dune movement and helped encourage the build‐up of sand seaward.

SECTION 2 SITE VISIT REPORT

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The dune system is considered healthy. The dunes are tall, stable and extensively vegetated with grasses as well as brambles.

One of two public access routes is through the dunes, the other being to the north of the beach leading from the road bridge onto the beach.

A stream flows onto the beach, meandering along the north of the beach.

The beach is an enclosed system where periodically sediment is moved offshore during storm events one year and then moves back in other years.

Sand tends to accumulate in the rocky embayments that can be seen when the tide is out.

The beach (up to the high tide water mark) is part of the nationally designated Padstow Bay and Surrounds Marine Conservation Zone (MCZ) designated to conserve the diversity of nationally rare, threatened and representative habitats and species in the area. The MCZ includes the tidal stream channel up to the bridge and road.

2.2.2 Issues Within parts of the local community there is a perception that when the dunes erode as a result of channel movement, the erosion is detrimental to the dune system, habitats, safety of the public and access onto the beach.

During storm events waves reach the dune toe. Dunes and beach are eroded and sediment is redistributed or moved offshore. When combined with heavy rainfall events, where the stream deposits more sediment onto the beach, a berm has formed and the stream has tended to divert, changing course southwards along the toe of the dunes. The stream channel itself erodes the frontal dunes and allows the sea to reach the dune toe, resulting in exacerbated erosion. This is perceived to create the following issues:

Safety hazard with regards to accessing the beach due to cliffing of the dune face.

The stream erodes and damages the dune system.

Erosion of the dune system resulting in habitat loss.

There are two clear sets of opinion in relation to how the stream should be managed in the future, as follows:

Non‐intervention

Active intervention.

Two years ago during the winter of 2014/15, high rainfall resulted in large volumes of sediment from the stream being deposited on the beach. Incoming tides moved sediment up the beach resulting in the formation of a bank in the north‐east of the bay. The bank effectively formed a barrier which diverted the stream south along the toe of the dunes, causing significant erosion of the frontal dunes. In January 2015, intervention without consent took place where a group of active residents dug a new straight channel to move the stream back along the north of the beach (see Photo 8). Reinstatement of the stream towards the north of the beach had an immediate effect of reducing the dune erosion.

During the winter of 2015/16, the stream again relocated along the dune toe, resulting in erosion of the dunes. However during this time, the stream was allowed to meander and move position naturally and subsequently, over time, the stream has moved again back to a more natural alignment to the north.

According to Cornwall Council, the greatest risk at Porthcothan is of surge waves during storm events up and under the B3276 Road Bridge which could result in structural damage or failure. Therefore it is the bridge and road that is most at risk. The natural channel meanders down the beach and a berm of sand in the northern meander provides a line of defence by dissipating wave energy. Relocating the channel straight along the north of the beach will exacerbate this risk under storm conditions, as the channel would allow waves to easily reach the bridge.

During the storm two years ago the reeds along the stream were eroded completely. The reeds are now re‐growing along the bank of the stream in the dunes.

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Herringbone tiles / brick banks alongside the bridge have been removed over time by members of the public.

2.2.3 Other notes Historic photographs and postcards of Porthcothan Bay were provided following the site visit by a local resident, Jane Darke. Copies of these are included in Appendix A.

2.3 Photos

Photo 1 View from beach upstream towards the B3276 Road Bridge.


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Photo 2 View from the B3276 Road Bridge looking downstream towards the sea.

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Photo 3 View of the stream as it flows out across the beach towards the sea.

Photo 4 View from the beach looking back across the stream towards the dunes.


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Photo 5 View along the front of the dunes, with coastguard station in front and properties on high ground behind; also shows the seaward end of the access path through dunes (red circle).

Photo 6 Cliffing along the dune face.

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Photo 7 Footpath access to the beach along the north side of the stream and the dunes.


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Photo 8 Stream after intervention to relocate the channel through the berm (source: Andrew Marriott)

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3 Environmental Characteristics 3.1 Introduction The purpose of this document is to identify key environmental features within and near the Study Area. This is to ensure that appropriate consideration of these features is made when analysing a future Beach and Dune Management Plan (BDMP) for Porthcothan (including ongoing monitoring and maintenance works and any new works that may be required) in the later stages of the BDMP development.

It should be noted that the level of detail presented in this document allows for an initial appraisal of environmental features to provide for an environmentally sustainable future management regime. This does not negate the requirement for future detailed environmental assessment which may be required to support consent applications or prejudge the scope of the assessment. Background information on possible consenting requirements and legislative basis are described in the methodology section below.

3.2 Methodology Conservation designations and their qualifying interest features, and UK priority BAP habitats that lie within the study area or within 2km have been described and will require consideration during the development of the BDMP. Only those features that are currently considered relevant to the Study Area, i.e. they are likely to be impacted upon or are likely to have an influence on the proposed scheme, have been described.

The exception to this is Special Protected Areas (SPAs). In this case, SPA sites have been considered within around 150km of the BDMP area and on the basis of bird‐habitat connectivity (i.e. how the birds use the habitat and so depend on different resources, for example estuarine mudflats and fully marine areas, at different stages of the tidal cycle).

The designation information has been sourced using the online interactive mapping tool Magic http://www.magic.gov.uk/.

3.2.1 Designated Nature Conservation sites and Protected Habitats The following section describes the nature conservation designations and their qualifying interests that have been considered.

3.2.1.1 International Nature Conservation Sites The Natura 2000 European network of protected sites represents areas of the highest value for natural habitats and species of plants and animals that are rare, endangered or vulnerable in the European Community.

Special Areas of Conservation (SACs) are strictly protected sites designated under the EC Habitats Directive, and contribute to conserving habitat and species identified in Annexes I and II of the Directive.

Special Protection Areas (SPAs) are strictly protected sites classified in accordance with Article 4 of the EC Birds Directive, which came into force in April 1979. They are classified for rare and vulnerable birds (as listed on Annex I of the Directive), and for regularly occurring migratory species.

3.2.1.2 National and Local Conservation sites Site of Special Scientific Interest (SSSI) sites are nationally designated sites, selected for being

the best examples of our natural heritage in terms of wildlife habitats, geological features or landforms. A SSSI area is notified as being of special interest under the Wildlife and Countryside Act 1981. Geological SSSI sites may also afford further designation as Geological Conservation Review sites (GCR) that make a special contribution to our understanding and appreciation of Earth science and the geological history of Britain, which stretches back hundreds of millions of years.

SECTION 3 ENVIRONMENTAL CHARACTERISTICS

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Marine Conservation Zones (MCZs). The Marine and Coastal Access Act 2009 allows for the creation of MCZs. MCZs protect a range of nationally important marine wildlife, habitats, geology and geomorphology, and can be designated anywhere in English and Welsh territorial and UK offshore waters. 27 MCZs were designated in 2013 with a further round of six recommended MCZs (rMCZ) are being considered for 2015.

Local Nature Reserves (LNRs) are declared and managed for nature conservation by local authorities under the National Parks and Access to the Countryside Act 1949, and provide opportunities for research and education, or simply enjoying and having contact with nature.

3.2.2 Habitats and Species The government has a commitment “to conserve and enhance the biological diversity within the UK and to contribute to the conservation of global biodiversity through all appropriate mechanisms.”

Biodiversity Action Plans (BAPs) were first developed at a national and local level to protect and enhance the diversity of flora and fauna. The UK BAP (Biodiversity: The UK Action Plan, 2004) set out action plans for priority species and habitats. As a result of devolution, and new country‐level and international requirements, much of the work previously carried out by the UK BAP is now focussed at a country‐level rather than a UK‐level, and the UK BAP was succeeded by the 'UK Post‐2010 Biodiversity Framework' in July 2012. The UK list of priority habitats, however, remains an important reference source and has been used to help draw up statutory lists of priority habitats in England, as required under Section 41 (England) of the Natural Environment and Rural Communities (NERC) Act 2006. Habitats and species of principal importance, which could potentially be affected by the study are considered.

3.2.3 Heritage Designations World Heritage Sites are designated by UNESCO to meet the UK's commitments under the World Heritage Convention. Sites are designated for their globally important cultural or natural interest and require appropriate management and protection measures.

Historic and archaeological sites of significance are designated as historical assets by Historic England and include listed historic buildings, scheduled monuments, registered parks and gardens, battlefields and protected wreck sites. Their designations are afforded to protect against any future loss of their significance.

Heritage Coast is a section of coast exceeding one mile in length that is of exceptionally fine scenic quality, substantially undeveloped and containing features of special significance and interest.

3.2.4 Landscape Designations Area of Outstanding Natural Beauty (AONB) are designated under the National Parks and Access to the Countryside Act 1949, amended in the Environment Act 1995, with responsibility of care assumed by local authorities and the rural community.

3.3 Environmental Setting The Study Area contains the following nature conservation designations. These are central in the consideration of options for the beach and dune management plan:

Padstow Marine Conservation Zone.

The Cornwall Area of Outstanding Natural Beauty (AONB).

Listed buildings.

The study area is directly adjacent to the following nature conservation designation, and is also central in the consideration of options for the beach and dune management plan:

Bristol Channel Approaches possible Special Area of Conservation (pSAC).

The following nature conservation designations and their qualifying interest features lie in close proximity to the Study Area:

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Bedruthan Steps and Park Head SSSI.

These features are shown on Figure 3.1 and discussed in further detail below.

Figure 3.1 Environmental designation features in the vicinity of the Porthcothan BDMP area.

3.4 Ecology 3.4.1 Designated Nature Conservation Sites

Padstow Bay and Surrounds Marine Conservation Zone includes Porthcothan Beach up to the high tide water mark and includes the stream channel outlet that runs onto the beach from under the road bridge on the northern side. The MCZ is designated for protection of exposed cliffs, rocky shores, sandy wave‐exposed bays, rocky outcrops and reefs that support rich underwater habitats and benthic communities. An MCZ assessment may be required dependant on the proposed actions of the BDMP.

The MCZ protects seven types of seabed habitat and two marine species as listed in Table 3.1.

Table 3.1 Padstow Bay and Surrounds Marine Conservation Zone features.

Padstow Bay and Surrounds MCZ features

General management approach

Present within Porthcothan BDMP

boundary

Intertidal coarse sediment Maintain in favourable condition

Intertidal sand and muddy sand

Maintain in favourable condition

Moderate energy intertidal rock


No records


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Padstow Bay and Surrounds MCZ features

General management approach

Present within Porthcothan BDMP

boundary

Moderate energy infra‐littoral; rock


No records

High energy intertidal rock Maintain in favourable condition

High energy infra‐littoral rock Maintain in favourable condition

No records

High energy circa‐littoral rock Maintain in favourable condition

No records

Pink sea‐fan (eunicella verrucosa)


No records. Potential to be

present below MLW adjacent to site

Spiny Lobster (Palinurus

elephas) Recover to favourable

condition No records.

Potential to be present during high tide and below MLW

adjacent to site

Bristol Channel Approaches possible Special Area of Conservation (pSAC) is located from mean low water at Porthcothan. The large geographical area of the SAC is proposed to be designated for protection and management of the wide‐ranging highly mobile Annex II species harbour porpoise (Phocoena phocoena) and its habitat. A Habitats Regulations Assessment may be required depending on the proposed actions of the BDMP.

Bedruthan Steps and Park Head SSSI is located approximately 0.6km south of Porthcothan and designated for biological and geological intersts. Biologically the site supports features of important maritime cliff species Armeria maritima ‐ Cerastium diffusum ssp. diffusum maritime therophyte community, grassland species Festuca rubra, Armeria maritima, Festuca rubra and Holcus lanatus, and lowland heath (calluna vulgaris, Scilla verna and Ulex gallii).The geological interests are described in Section 3.5 below.

The following designated sites have been identified and considered or discounted for bird‐habitat connectivity between the protected area and the site (see Figure 3.2):

Falmouth Bay to St Austell Bay pSPA is approximately 28km from Porthcothan at its nearest point. The proposed SPA (pSPA) supports rare wintering birds and diving birds that are proposed for designation under the Birds Directive (2009/147/EC). The pSPA is a large area, and encompasses the Fal and Helford SAC within the pSPAs north western section. This site is designated under article 4 (4) of the Habitats Directive (92/43/EEC) for the following Annex 1 habitats: Sandbanks which are slightly covered by sea water all the time; Mudflats and sandflats not covered by seawater at low tide; Large shallow inlets and bays that include low tidal sandbanks and Atlantic salt meadows (Glauco‐Puccinellietalia maritimae). Other Annex I habitats that are present as a qualifying feature of the SAC but not the primary reason for selection include Estuaries and Reefs and includes the Annex II plant species Shore dock Rumex rupestris. Connectivity with Porthcothan Bay and the SAC/pSPA is possible. Habitat, as described in the MCZ that surrounds Porthcothan Bay (as mentioned above) may support seabirds and diving birds, and consideration may be required.

Tamar Estuaries complex SPA is approximately 51km northeast from Porthcothan at its nearest point. The estuary system is a large marine inlet on the English Channel coast comprising the estuaries of the Rivers Tamar, Lynher and Tavy. Habitats include extensive tidal mud‐flats

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bordered by saltmarsh communities. The mud‐flats contain extensive and varied infaunal communities rich in bivalves and other invertebrates, and feeding grounds for waterbirds in numbers of European importance. Saltmarshes provide important feeding and roosting areas for large numbers of wintering and passage waterbirds. This site qualifies under Article 4.1 of the Directive (79/409/EEC) by supporting populations of Little Egret Egretta garzetta (on passage, and a population over winter) and Avocet Recurvirostra avosetta (over winter). Connectivity is possible but likely low due to a lack of estuarine mudflat and saltmarsh habitat at Porthcothan.

Marizion Marsh SPA/SSSI is approximately 52km south of Porthcothan from its nearest point. The marsh is at the mouth of a wide coastal valley, separated from the sea by a shingle bar with fringing sand dunes. The marsh is important for passage and wintering birds associated in particular with the extensive reedbed. The site qualifies under Article 4.1 of the Directive (79/409/EEC) by supporting populations of Annex I species Aquatic Warbler Acrocephalus paludicola (in passage) and Bittern Botaurus stellaris (over winter). Connectivity between the SPA/SSSI and Porthcothan Bay is unlikely due the absence of similar freshwater habitat.

Isles of Scilly SPA is approximately 106km from Porthcothan at its closest point. The SPA qualifies for its seabird assemblage of international importance and breeding seabird assemblage of European importance. The isolated nature of the islands and rocks, together with their low levels of disturbance and predation, makes them particularly suitable for nesting seabirds. This site qualifies under Article 4.1 of the Directive (79/409/EEC) by supporting populations of European importance of the following Annex I species Storm Petrel Hydrobates pelagicus and Lesser Black‐backed Gull Larus fuscus. The site also qualifies under Article 4.2 of the Directive (79/409/EEC) for regularly supporting a seabird assemblage of international importance of at least 20,000 seabirds. The SPA boundary only encompasses those areas used for nesting. The vast majority of the feeding areas used by the seabirds are marine waters outside the SPA. Connectivity with feeding areas seaward around Porthcothan is feasible.

The Exe Estuary SPA (approximately 109km from Porthcothan Bay at its nearest point) is a complex of coastal habitats waters, foreshore, low‐lying land, three saltmarshes and an unusual double spit across the mouth of the estuary, and the sand dunes of Dawlish Warren. The mud and sandflats support Eelgrass Zostera spp. and Enteromorpha beds, and contain an abundance of invertebrates including extensive Mussel Mytilus edulis beds, which together provide rich feeding habitats for wintering waders and wildfowl. Site qualifies under Article 4.1 of the Directive (79/409/EEC) by supporting populations of Annex I species Avocet Recurvirostra avosetta and Slavonian Grebe Podiceps auritus (over winter) and qualifies under Article 4.2 of the Directive (79/409/EEC) as a wetland of international importance for regularly supporting at least 20,000 waterfowl. Connectivity is likely low due to a lack of estuarine habitat present at Porthcothan Bay to support the associated species.


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Figure 3.2 Potential bird‐habitat connectivity between the protected area and the Porthcothan BDMP site.

3.4.2 Biodiversity Action Plan (BAP) Habitats and Species The following are listed as UK priority BAP habitats and are either represented in the Study Area or are within 1km. Bullet point habitats have been identified from the national archives website1 (NB: they may have slightly different titles to those already bulleted below):

Coastal Sand Dunes

Maritime cliff and slope

Spiny lobster (Palinurus elephas).

There are no formal records identified at Porthcothan, but as a designated feature of the MCZ, spiny lobster has potential to be present within the intertidal zone (during high tide) and within inshore waters adjacent to the BMP area. Spiny lobster needs to be considered by any potential BMP works.

Pink sea‐fan (eunicella verrucosa).

There are no formal records identified at Porthcothan, but as a designated feature of the MCZ, pink sea fan has potential to be present within inshore waters adjacent to the BMP area and needs to be considered by any potential BMP works.

Harbour porpoise (Phocoena phocoena). European protected species and designated feature of the pSAC.

Harbour porpoise are highly mobile species and have potential to be present within the intertidal area adjacent to the BMP area. Any proposed works needs to consider harbour porpoise and harbour porpoise habitat.

1http://webarchive.nationalarchives.gov.uk/20140605090108/http:/www.naturalengland.org.uk/ourwork/conservation/biodiversity/protectandmanage/habsandspeciesimportance.aspx ‐ go to ‘list of habitats’.

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Note, no baseline habitat assessment report has been undertaken by Cornwall Council for Porthcothan to date, therefore priority BAP habitat has been identified using records described in the online environmental mapping tool MAGIC in combination with the citation descriptions of habitat as described for the designated sites. Only habitats that are considered relevant to the Study Area, i.e. they are likely to be impacted upon or are likely to have an influence on beach management options, have been described. Firm confirmation of priority BAP habitat would require an ecological assessment.

3.5 Designated Geological Conservation Sites There are no designated sites for earth sciences at Porthcothan, however the following nationally and regionally important designations are located nearby:

Bedruthan Steps and Park Head SSSI is located approximately 0.6km south of Porthcothan. The SSSI is designated for biological (as noted above in Section 3.4.1) and geological interests. Geologically the cliffs are of importance for rich fossil fauna, within extensive exposures of grey Devonian slates indicating an Eifelian Age. It is the best site of this type in Cornwall.

Bedruthan Steps Geological Conservation Review site is recognised for its source of rare fish fossils representing possibly a late and large pteraspid. The specimens are rare elsewhere in north Cornwall, and may be some of the last recorded pteraspids, and so considered of great importance.

3.6 Archaeology and Cultural Heritage 3.6.1 Landscape Setting The importance of landscape to the Porthcothan Bay area is recognised by the following nationally and regionally important designations (see Figure 3.1 above):

The Cornwall Area of Outstanding Natural Beauty (Trevose Head to Stepper Point) has an extremely varied coastal scenery but can be characterised by sandy bays giving way to sand dunes and small hamlets /holiday villages (of which Porthcothan is one), small coves, high cliffs and stacks and a gently rolling plateau rising to higher ground inland with panoramic views.

3.6.2 Archaeology and Cultural Heritage A number of listed buildings are present within the area (see Figure 3.1 above).

3.7 Anthropogenic Pressures From observations during the site visit May 2016 (refer to Section 2), there are few anthropogenic pressures affecting the natural dynamics of the site. However, monitoring could be a suggested in order to establish any changes over time to the main dunes and area where the dunes are re‐building cliff side of the stream but are currently bare of vegetation.

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4 Coastal Processes Understanding 4.1 Introduction This section presents the findings of a desk‐based study that draws on existing information following a review of existing literature and data analysis to assess the coastal processes and shoreline change at Porthcothan, located on the north coast of Cornwall as shown in Figure 1.3 above.

The work draws primarily from key data sources, including the 2009 sediment budget report (Halcrow, 2009b), the latest Shoreline Management Plan (SMP2) (Royal Haskoning, 2011a, b and c), latest beach profile monitoring data collected as part of the South West Regional Coastal Monitoring Programme (Plymouth Coastal Observatory (PCO), 2014a, b and c) and anecdotal data received from stakeholders during a site visit (refer to Section 2).

The section is split into the following sub‐sections:

Shoreline Processes Overview – summary of the key characteristics of the coastline including details on geomorphology, past shoreline evolution and management intervention.

Forcing Factors – description of the typical wave climate, storm waves and tidal information. The best available wave information has been sourced for this study and includes wave buoy data collected as part of the South West Regional Monitoring Programme by Plymouth Coastal Observatory (PCO).

Sediment Dynamics – description of the key sediment transport pathways and sediment sources.

Historical Shoreline Change – drawing primarily from the work undertaken for the 2009 Cornwall Sand Dune and Beach Management Strategy, and a summary of change between 2001 and 2009 from analysis of aerial photographs.

New Shoreline and Beach Profile Analysis – review of the monitoring data by (PCO) collected between 2007 and 2014, including beach profile data and post‐storm volume analysis.

Future shoreline evolution – provides broad‐level prediction of how the shoreline in this area is expected to evolve in the coming 100 years.

Summary – provides a summary of the analysis presented in the preceding sections.

4.2 Shoreline Processes Overview 4.2.1 Key Characteristics of the Coastline Today Porthcothan Bay is located on the north coast of Cornwall, between Trevose Head and Park Head, south of Treyarnon Bay (refer to Figure 4.1). The westerly facing bay is exposed to dominant Atlantic waves and weather systems. Futurecoast (Halcrow, 2002) suggests that there is no interaction between the beaches along this coast in terms of sediment exchange. This is probably true given the deeply incised nature of this section of coast and its swash aligned tendencies.

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Figure 4.1 Porthcothan Ordnance Survey location map (Source: Halcrow, 2009a).

The bay is situated between two rocky headlands of hard resistant Devonian slates (Royal Haskoning, 2011b) to the north and south. At low tide Porthcothan Bay is long and narrow compared to at high tide where the remaining beach reduces in size considerably. An area of well‐established fringing dune line the backshore of the bay, along with a small stream which discharges onto the beach in the north east.

SECTION 4 COASTAL PROCESSES UNDERSTANDING

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Figure 4.2 Porthcothan dune extents (Source: Halcrow, 2009a).

Porthcothan dunes (Figure 4.2) are high, hummocky and well vegetated with grasses and brambles. The dune face is steep with notable cliffing (Figure 4.3), consequently the lifeguard station has been moved from within the dunes, onto the beach (Figure 4.4). However, analysis of historical maps indicates a healthy, stable dune system. The dune system formed after the war when fences were placed at the back of the beach. Sand accumulated and the dunes have grown considerably over recent decades.

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Figure 4.3 Porthcothan dunes.

Figure 4.4 Porthcothan lifeguard station.

A stream flows onto the beach, meandering along the north of the beach (Figure 4.5). An accumulation of sand can be seen to the north of the meander, where beach levels are higher. During storm events waves reach the dune toe. The dunes and beach are eroded and sediment is moved offshore. When combined with heavy rainfall the stream deposits more sediment on the beach, specifically on the berm, which forms a barrier. As a result, the stream has periodically diverted course, relocating southwards


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along the toe of the dunes. Within parts of the local community there is a perception that when the dunes erode as a result of channel movement the erosion is detrimental to the dune system, habitats, safety of the public and access onto the beach. Two years ago, following relocation of the stream along the toe of the dunes and consequent erosion, intervention without appropriate consent being granted by the MMO and other statutory bodies took place where a group of active residents dug a new straight channel, moving the stream back along the north of the beach. Subsequently, over time, the stream has moved again back to a more natural alignment.

Figure 4.5 Stream flowing onto Porthcothan Beach.

Erosion and flood risk at Porthcothan Bay is low (Royal Haskoning, 2011a). This is because much of the development in the area is located in higher land or set‐back from the coast. However, there are isolated properties and a section of the B3276 road at risk from erosion in the long term.

Porthcothan Bay is located within SMP2 PDZ13 / Management Area 33 and the future management policy for the frontage for the next 100 years is No Active Intervention (NAI) with localised Hold the Line (HTL) (Royal Haskoning, 2011a): ‘a non‐interventional approach is best to manage dune area but it would be acceptable to HTL along short section of road adjacent to the rear of the beach.’ The NAI approach will allow the dune and beach area to respond naturally to sea level rise. Holding the line along the short section of defences adjacent to the B3276 road to the rear of the beach, is considered justifiable, however a more sustainable approach in the long term may be to realign the road.

4.2.2 Forcing Factors 4.2.2.1 Typical Waves The coastline at Porthcothan is orientated north‐south, with the beach facing west and dunes approximately north‐west. The predominant wave direction along the north coast of Cornwall is reported (Royal Haskoning, 2011b) to be from the west to north‐west (approaching from 270o – 315o), however, large swell waves from the south to southwest will refract around the Lands End Peninsula and reach the most westerly facing beaches, (with reduced energy) (Royal Haskoning, 2011b), such as Porthcothan Bay.

The Perranporth Directional Waverider Buoy, operated as part of the South West Regional Coastal Monitoring Programme (SWRCMP), is the nearest wave buoy to Porthcothan Bay, and has been

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reviewed for this study (refer to Figure 4.6 for the wave data point). The wave buoy is located approximately 20 miles south‐west from Porthcothan Bay, and provides a record of wave height for a seven year period between 18th December 2006 and 30th June 2014. A plot of wave height in Figure 4.7 shows that the predominant wave direction in this area is from the west. The data set also indicates significant wave heights frequently exceed 5m during the winter months and that wave periods of 15 seconds (i.e. powerful swell waves generated by storms offshore) and higher are not uncommon (Royal Haskoning, 2011b).

Figure 4.6 Map showing the location of the wave data collection point.


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Figure 4.7 Offshore wave height recorded by the Perranporth Directional Waverider Buoy between 18th December 2006 and 30th June 2014 (PCO, 2014a).

4.2.2.2 Storm Waves Storm analysis undertaken by PCO (2014b) provides an overview of the storm conditions recorded by the Perranporth Directional Waverider Buoy since 2007.

For each wave buoy in the SWRCMP, an individual storm threshold is set. A storm event is defined when significant wave heights equivalent to the 0.25 year return period (i.e. the threshold wave height (Hs) for 2 to 4 storms in an average year) occurs for set period of time (i.e. 16 hours). The significant wave height is calculated when a 5 year time series of data becomes available for the wave buoy and is then reset each year. Prior to that, the height is based on an educated conservative guess from looking at the wave data available. The reason that the 0.25 year return period is used is because the SWRCMP have found that in general there are 3 to 4 storms in any one year that result in the movement significant amounts of sediment.

For their reporting, PCO produce a storm calendar. The calendar includes a graph, where each dot represents a storm (i.e. where the Hs exceeds the storm threshold) and shows the Hs for that particular storm. PCO plot the significant wave height for the 1 year return period for that particular buoy on the graph (calculated in the same way as significant wave height for the 0.25 year return period) as a red line. Where storms plot above the red line they are considered to be more severe/extreme and are listed in a separate table. The storm calendar and table for the Perranporth Directional Waverider Buoy are presented in Figure 4.8 and Table 4.1 respectively.

The storm calendar shows that eight severe/extreme storms have exceeded the 1 year Return Period since 2007; three of those storms (38 %) occurred between October 2013 and February 2014.

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Figure 4.8 Storm calendar for Perranporth (source: PCO, 2014b). Table 4.1 Storms exceeding 1 year Return Period at Perranporth since deployment in 2007. Those occurring during the storm season October 2013 to February 2014 are shaded pink (source: PC0, 2014b).

Date Wave Height (m) Return Period

01/02/2014 7.28 Greater than 1 in 20 years

02/11/2013 7.06 1 in 10 years

27/12/2013 6.81 1 in 5 years

15/12/2011 6.75 1 in 5 years

12/03/2008 6.53 1 in 3 years

10/03/2008 6.37 1 in 2 years

11/11/2010 6.3 1 in 1 year

31/03/2010 6.25 1 in 1 year

4.2.2.3 Tides Tidal levels have been extracted from the current Admiralty Tide Tables (UKHO, 2013) for the closest location with the best available data, in this case Newquay, and converted to Ordnance Datum (mOD), see Table 4.2.


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Table 4.2 Tide levels (in mOD) for Newquay, adjusted from standard port Milford Haven.

Tidal Condition Tide Level (mOD)

Highest Astronomical Tide (HAT) Data not available

Mean High Water Spring (MHWS) 3.40

Mean High Water Neap (MHWN) 2.00

Mean Sea Level (MSL) 0.38

Mean Low Water Neap (MLWN) ‐1.10

Mean Low Water Spring (MLWS) ‐3.00

Lowest Astronomical Tide (LAT) Data not available

4.2.3 Sediment Dynamics Sediment transport at Porthcothan Bay is dominated by the on/offshore movement of material between the beach and dunes (Halcrow, 1999a; Halcrow, 2009b). In winter, storm waves erode the dune front releasing sediment onto the beach and redistributes the material to the small rocky coves (Figure 4.9) that can be seen when the tide is out, and to the offshore, such as occurred in the 2013/2014 storms. In calmer conditions, this material is returned to the dunes through wave action and wind‐blown transport.

Figure 4.9 Sand accumulating in rocky embayments within Porthcothan Bay.

The rock headlands which bound the bay to the north and south, and Trescore Islands to the west prevent sediment movement outside of the bay. Consequently, Porthcothan Bay is a closed sediment cell with no significant alongshore exchange of material (Halcrow, 2009b).

The main contemporary beach sediment source is from offshore carbonate shell material (Halcrow, 2002), with limited sediments supplied from cliffs adjacent to the beach. The stream is also unlikely to provide a significant sediment input to the system.

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4.2.4 Historical Shoreline Change A number of photographs and postcards of Porthcothan Bay from St Eval Parish archive, dated between 1908 and 1936, are included in Appendix A. The images show a much smaller extent of dunes compared to that observed today, suggesting a growth of the dunes of approximately 60m seaward over the last 80 years.

Aerial photographs in Figure 4.10 (2001), Figure 4.11 (2005) and Figure 4.12 (2009) show little change in dune position, but clearly show how the position of the stream flowing through the beach has changed over time. The dunes to the south of the stream, where it discharges onto the beach, have receded slightly as a result of natural channel movement. Figure 4.11 shows evidence of two channels, where the channel has relocated along the dune toe, but then is slowly re‐orientating to its previous equilibrium position.

There is also evidence of frontal dune erosion which has resulted in the lifeguard station (blue circle) being moved onto the beach (Figures 4.11 and 4.12) from its location on the dunes (Figure 4.10).

During the winter of 2014/15, rapid relocation of the stream along the dune toe, combined with exceptional tides, resulted in a significant loss of the dunes through erosion, causing unprecedented changes to the beach and dune profiles (Figure 4.13). Anecdotal evidence suggests that continual erosion of the dunes by the stream in November 2014 over a number of days resulted in between 6m and 10m of frontal dune erosion (Figure 4.14).

Further erosion of the dune system occurred in the winter of 2015/16, when the stream again relocated along the dune toe.

Direct erosion of the dunes by the sea occurs infrequently, predominantly when high spring tides and storms coincide.

Figure 4.10 Porthcothan dunes and stream, 2001 (source: Google Earth 2016).


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Figure 4.13 Relocation of the stream along the front of the dune system, November 2014 (source: Andrew Marriott)


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Figure 4.14 Frontal dune erosion, November 2014. (source: Andrew Marriott)

4.3 Shoreline and Beach Profile Analysis Beach profile monitoring undertaken by PCO for the SWRCMP, provides recent data and analysis for the beach at Porthcothan Bay. A summary of the findings from the latest annual survey report (PCO, 2014a) are presented in this section and provide an overview of beach profile change in the year, between Spring 2013 and Spring 2014, and over the longer‐term from the baseline survey in 2007 to the most recent survey in Spring 2014. It should be noted that the assessment of CSA for the profiles at Porthcothan Bay exclude the dunes, covering only beach change.

Between Spring 2013 and Spring 2014 (refer to Figure 4.13), the northern and central profiles have lost material, with the northern profile, 7a02034, losing >30m2, equating to 34% in cross‐sectional area (CSA).

Over the longer term, between 2007 and Spring 2014 (refer to Figure 4.14), the trend is for erosion in the north and central areas of the bay, profile 7a02034 (CSA reduction of 8%) and profile 7a02031 (CSA reduction of 4%) and slight accretion to the south of the bay, profile 7a02028 (CSA change of 3%).

Mapping of the Mean High Water contour (refer to Figure 4.15) shows that the upper beach position has fluctuated over the survey period, with no clear trend.

Observations made during the site visit on the 12th March 2015 found the dunes to be overall stable but with a steep cliffed face.

As part of the SWRCMP, PCO have also prepared two reports (PCO, 2014b and 2014c), which examine the change to a selection of the beaches along the south‐west coast, with a view to identify how beach change occurring as a result of the 2013/2014 winter storms compares to the longer‐term behaviour of the beach. However, analysis of beach volume change and a topographic difference model has not been completed for Porthcothan Bay.

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Figure 4.13 Beach profile change at Porthcothan Bay Spring 2013 to Spring 2014 (source: PCO, 2014a).

Figure 4.14 Beach profile change at Porthcothan Bay baseline 2007 to Spring 2014 (source: PCO, 2014a).


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Figure 4.15 MHW contour change at Porthcothan Bay (source: PCO, 2014a).

4.4 Future Shoreline Evolution The pocket beach at Porthcothan is likely to maintain its overall form in the future. Marine carbonate sources will continue to feed a supply of sand. The resistant cliffs will continue to erode slowly. Flood risk to the low‐lying backshore area will increase as sea levels rise.

There is a potential for some narrowing of the foreshore and dune erosion as sea levels rise and during storm events, however, the Shoreline Management Plan (SMP) states that the dunes are not expected to erode significantly and should recover as sediment exchange will continue freely between the beach and dune system (Royal Haskoning 2011a).

With climate change and increased storm events, the combination of high intensity rainfall events and storms could result in further instances where the channel is diverted south along the dune frontage. There is therefore potential for accelerated dune loss episodes in the future as a result.

Figure 4.16 highlights the predicted erosion risk to the hinterland stated in the SMP (Royal Haskoning, 2001a). Under a no active intervention scenario, the SMP predicts that if the dune system is lost then there is risk to the bridge, road and houses beyond over the 100 year appraisal period.

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Figure 4.16 Porthcothan flood and erosion risk (Source: Royal Haskoning, 2011a).

4.5 Summary The beach at Porthcothan Bay is west facing and exposed to the predominant westerly wave regime. As a result alongshore transport is limited. Sediment transport is therefore dominated by an onshore‐offshore movement of material. An area of well‐established fringing dune lines the backshore of the bay, along with a small stream which discharges onto the beach in the north east. The dune system formed after the war when fences were placed at the back of the beach. Sand accumulated and the dunes have grown considerably over recent decades. Today the high, hummocky, vegetated dunes are considered stable. As the dunes erode during storms, material is moved offshore. Increase in the size of the berm to the north, due to deposit of fluvial material during high rain events, has at times diverted the stream southwards along the dune toe, resulting in erosion of the fronting dunes for periods of time.

Beach profile analysis suggests that over the longer‐term (2007 to 2014) the beach to the north and centre of the bay is eroding and the beach to the south is accreting. These trends are generally mirrored by on‐the‐ground observations, as material is lost from the beach temporarily and returned over time.

Dune erosion occurs during storm events and the dunes suffered significant erosion during the 2014/15 storms, exacerbated by the stream channel changing course. In January 2014, intervention by a group of active residents moved the stream back towards the north and erosion was considerably reduced. In the winter of 2015/16 the stream relocated again along the dune toe and resulted in dune erosion, however this time no intervention took place and the channel moved back towards the north naturally over time.

Aerial photographs between 2005 and 2009 show evidence of channel movement from its position in the north part of the bay, to relocating along the dune toe, to repositioning back to along the northern shore. This is a process that will repeat itself in the future.

SECTION 5 DUNE INVENTORY SITE SUMMARY

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5 Dune Inventory Site Summary DUNE SYSTEM PORTHCOTHAN

CHARACTERISTICS

LOCATION MAP

See Figure 1.2.

AERIAL PHOTOGRAPH

See Figure 1.4.

DUNE EXTENT

See Figure 1.4.

AREA OF SITE

Active 1 ha

Inactive 0 ha

Total 1 ha

DUNE TYPE Hummocky.

MORPHOLOGICAL FEATURES OF DUNES

Degraded dune system.

Cliffing of dune face at northern end of beach.

Meandering stream through site.

PAST (150 YRS) EVOLUTION OF DUNES

Analysis of historical maps indicates a stable dune system.

Some development behind beach and dunes.

VEGETATION TYPE

Yellow Dune, Grey Dune, Scrub.

Non‐native species.

BACKSHORE CHARACTERISTICS

Flat land behind low dunes on which is some development.

Land rises gently from valley base.

COASTAL SETTING

Wide flat sandy bay flanked by cliffs.

Stream discharges along northern side of bay with streamlets and ponds in lower foreshore.

Beach material composed largely of carbonate shell material.

Bay bounded by rock headlands which prevent sediment transport outside of the bay.

North West facing dunes.

DRIVERS

LINKS TO ADJACENT COAST

Closed sediment cell with no significant alongshore exchange of material to adjacent embayments.

WIND ENERGY

No contemporary data identified. Refer to SMP1 (Halcrow, 1999) for historical data.

WAVE ENERGY

See Sections 4.2.2.1 and 4.2.2.2.

WATER LEVELS

See Section 4.2.2.3.

SEDIMENT BUDGET Carbonate material is main contemporary beach sediment source.

PRESSURES

ENVIRONMENTAL DESIGNATIONS

Bedruthan Steps and Park Head SSSI (biological and geological).

Bedruthan Steps Geological Conservation Review site.

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Padstow Bay and Surrounds Marine Conservation Zone.

Bristol Channel Approaches possible Special Area of Conservation (pSAC).

Potential UK BAP Priority Habitats & Species with management objectives (Coastal Sand Dunes; Maritime Cliff and Slope; Spiny Lobster; Pink Sea‐fan; Harbour Porpoise).

See Sections 3.3, 3.4 and 3.5 also.

ARCHAEOLOGY/ HERITAGE

The Cornwall Area of Outstanding Natural Beauty (AONB).

Archaeological and Cultural Heritage in the form of a number of listed buildings (refer to Section 3.6.2).

LAND USE

Developed land behind and to south of beach and dunes.

RECREATIONAL PRESSURES

Evidence on aerial photographs of some access paths through dunes but little bare sand.

Sand blown onto road behind northern end of beach.

Café at entrance to beach.

SAND EXTRACTION/ DREDGING

None known of.

COASTAL DEFENCES None.

CURRENT MANAGEMENT PRACTICES

Warning sign for sand blown onto road.

Casual cleaning of beach by local wardens.

SHORELINE MANAGEMENT PLAN POLICY (from Royal Haskoning, 2011a)

Policy Unit 33.6 (Porthcothan Beach): o Short term = No Active Intervention (with localised Hold the

Line); medium term = No Active Intervention (with localised Hold the Line); long term = No Active Intervention (with localised Hold the Line).

o Policy intent = “A non‐interventional approach is best to manage dune area but it would be acceptable to HTL along short section of road adjacent to the rear of the beach.”

MANAGED BY

Dunes owned by Porthcothan Sand Dune Trust.

Beach managed by Cornwall Council.

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6 Future Beach & Dune Management Recommendations A key issue at Porthcothan Bay is the periodic relocation of the stream channel along the toe of the dunes and consequent perception that erosion of the dunes as a result of this is detrimental to the dune system, habitats and to public safety / access onto the beach.

Porthcothan Bay, including the beach, dunes and stream, is a naturally functioning system, where periodically the dunes are eroded during storms, material is drawn down from the dunes and beach to the offshore. Periodically when conditions are conducive, the stream channel relocates along the dune toe. Evidence presented in Section 4 has shown that over time, material is returned to the beach and dune system and the stream channel relocates back to its position in the north of the bay. Even when the stream channel has been artificially relocated to a straight position, the channel tends to find its own equilibrium position, forming meanders again over time. This is a process that will repeat itself in the future.

In the future, as sea levels rise, the risk of erosion of the bridge and road and resulting increases in flood risk upstream will be an issue. Artificial relocation of the channel to a straight position in the north will only exacerbate this risk, as storm waves will be funnelled up the channel and towards the bridge. However, the natural channel meanders down the beach and a berm of sand in the northern meander provides a line of defence by dissipating wave energy.

It is therefore recommended that the beach, dune and stream system to the north of the bay should be left to behave naturally. There is little benefit to any intervention in this system from a flood and erosion risk management or environmental management point of view. The implication of this approach in the long‐term for the road and bridge will need to be considered by the Highways Authority at a later date.

If as a result of allowing natural processes to occur, safe access to the beach from either of the two current footpaths is an issue, then the following can likely be done by local groups, subject to obtaining any consents that may be required from the local planning authority (planning permission), Natural England and the Marine Management Organisation (given the proximity of the MCZ to Porthcothan):

Re‐profile the dune face at the access point when required (i.e. become over‐steep for safe access).

Install temporary/removable (and relocatable) access measures such as steps, a bridge or stepping stone across the stream.

Relocate access paths through the dunes away from historic routes and undertake grass planting (such as marram grass or lyme grass) along the redundant path to help stabilise the dunes.

If during the summer period the channel cuts into the dune toe such that the dune is eroded back to the trigger point (approximately 30m of erosion back from the lifeguard hut ‐ see Figure 6.1), posing a significant amenity and health and safety access issue, then intervention could take place with limited works to relocate the stream by local groups, subject to obtaining any consents as outlined above. If such works are undertaken then the following conditions will apply:

The berm north of the stream should not be cut through and should be retained.

When relocating the stream, incorporate meanders around the berm (see Figure 6.1).

The cost for these measures would need to be funded from non‐Flood and Coastal Grant in Aid, i.e. from local funding sources, as it falls outside the scope of that funding source. In addition, if to be implemented, any consents required should be obtained beforehand.

In addition to the above, from a dunes BAP habitat perspective, monitoring of the dunes could also be undertaken by the local community in order to keep a record of any habitat changes over time; for example, anthropogenic impacts and extent of invasive/non‐native dune vegetation species. This could be taken forward in discussion with local environmental organisations.

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Figure 6.1 Porthcothan proposed beach and dune management strategy.

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7 References Cornwall AONB, 2016. 04 Trevose Head to Stepper Point. Internet site: http://www.cornwall‐

aonb.gov.uk/trevoseheadtostepperpoint/. Date accessed 10/5/2016.

Frampton, A.P.R. (2010). A review of amenity beach management. Journal of Coastal research, 26(6), 1112‐1122, November 2010.

Halcrow (2009a). Sand Dune Inventory. Cornwall Sand Dune and Beach Management Strategy. Report produced by Halcrow Group Limited for the Cornwall and Isles of Scilly Coastal Advisory Group, September 2009.

Halcrow (2009b). Sediment Budget Report. Cornwall Sand Dune and Beach Management Strategy. Report produced by Halcrow Group Limited for the Cornwall and Isles of Scilly Coastal Advisory Group, September 2009.

Halcrow (2002). Futurecoast CD. Produced by Halcrow Group Ltd for Defra.

Halcrow (1999a). Land’s End to Hartland Point Shoreline Management Plan. Volumes 1 to 4. Report produced by Halcrow Group Limited for Cornwall and Isles of Scilly Coastal Group.

Halcrow (1999b). Lizard Point to Land’s End Shoreline Management Plan. Volume 1 ‐ Strategy Document. Report produced by Halcrow Group Limited for the Cornwall and Isles of Scilly Coastal Group.

JNCC, 2007. Geological Conservation Review 1980 – 2007, Vulume 16, Chapter 7: Bedruthan Steps (GCR ID:2246). Viewed online at (internet site): http://jncc.defra.gov.uk/pdf/gcrdb/GCRsiteaccount2246.pdf/. Accessed 10/5/2016.

JNCC, 2012. The UK Biodiversity Action Plan (UK BAP) 1992‐2012. Internet site: http://jncc.defra.gov.uk/page‐5155/. Accessed 10/5/2016.

JNCC, 2016. Harbour Porpoise Possible Special Area of Conservation Consultation: Bristol Channel Approaches pSAC: site summary document and selection assessment document. Internet site: http://jncc.defra.gov.uk/default.aspx?page=7059/. Date accessed 10/5/2016.

JNCC and Defra, 2012. UK Post‐2010 Biodiversity Framework. Viewed online (internet site): http://jncc.defra.gov.uk/pdf/UK_Post2010_Bio‐Fwork.pdf/. Date Accessed 15/5/2016.

Natural England, 1986. Bedruthan Steps and Park Head SSSI, designated sites view. Internet site: https://designatedsites.naturalengland.org.uk/SiteDetail.aspx?SiteCode=S1002099&SiteName=&countyCode=6&responsiblePerson=/. Date accessed 10/5/2016.

Natural England, 2013. Padstow Bay and Surrounds MCZ Factsheet (MCZ039) Internet site: http://publications.naturalengland.org.uk/publication/5663997181296640?category=1721481/. Date accessed 10/5/2016.

National Archives Website. Internet site: http://webarchive.nationalarchives.gov.uk/20140605090108/http:/www.naturalengland.org.uk/ourwork/conservation/biodiversity/protectandmanage/habsandspeciesimportance.aspx. Date accessed: 09/5/2016.

Online interactive mapping tool Magic. Internet site: http://www.magic.gov.uk/. Date accessed: 10/5/2016.

Plymouth Coastal Observatory (PCO) (2014a). Annual Survey Report. Land’s End to Hartland Point. Report Number AR43. Report produced for the South West Regional Monitoring Programme, September 2014.

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Plymouth Coastal Observatory (PCO) (2014b). Review of South West Coast Beach Response to Wave Conditions During the Winter of 2013‐2014. Report Number SW SR01. Report produced for the South West Regional Monitoring Programme, June 2014.

Plymouth Coastal Observatory (PCO) (2014c). Review of South West Coast Beach Response to Wave Conditions During the Winter of 2013‐2014. Addendum: Beach Recovery Since Winter 2013‐2014. Report Number SW SR01A. Report produced for the South West Regional Monitoring Programme, September 2014.

Royal Haskoning (2011a). Cornwall and Isles of Scilly SMP2. Main Report, Final. Report produced by Royal Haskoning for the Cornwall and Isles of Scilly Coastal Advisory Group, February 2011.

Royal Haskoning (2011b). Cornwall and Isles of Scilly SMP2. Appendix C, Review of Coastal Processes and Geomorphology, Final Report. Report produced by Royal Haskoning for the Cornwall and Isles of Scilly Coastal Advisory Group, February 2011. Report reference 9T8801.

United Kingdom Hydrographic Office, UKHO (2013). Admiralty Tide Tables. Volume 1. United Kingdom and Ireland. Reference NP201‐13.

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Appendix A

Historic photographs and postcards of Porthcothan Bay. Source St Eval Parish Archive.

Photo A1 The Garceau brothers on the seaward side of Porthcothan bridge, circa 1908.

Photo A2 Porthcothan shop buildings sitting higher than the beach, circa pre 1910.

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Photo A3 Porthcothan Bay prior to the construction of the road, date unknown.

Photo A4 Postcard of Porthcothan beach and bridge, posted on 9th July 1926.

SECTION 7 REFERENCES

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Photo A5 Porthcothan, circa 1926.

Photo A6 Bab Darke on a boat by Porthcothan bridge looking towards the sea, circa 1928.

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Photo A7 Porthcothan Bay, 25th August 1936.

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