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University of the West of England BSc Geography and Environmental Management MANAGEMENT OF RIVERS AND COASTS (UBGMXD-30-3) COASTAL MANAGEMENT REPORT BREAN DOWN TO BURNHAM-ON-SEA: SECTION ‘C’ STUDENT NUMBER: 11020965 Tony Gregory

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Page 1: Coastal Management Report, 11020965 (1)

University of the West of EnglandBSc Geography and Environmental Management

Management of Rivers and Coasts (UBGMXD-30-3) Coastal Management Report Brean Down to Burnham-on-Sea: Section ‘C’

STUDENT NUMBER: 11020965

Tony Gregory

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

1. INTRODUCTION

Site location:

Brean Down (grid ref ST 29568 58709) to the north and Burnham-on-Sea (grid ref ST 29911

50572) to the south, stretches for 7 miles between the two locations (visit Somerset, 2014)

as shown by figure 1. The area in question is exposed to the Severn Estuary which is a

broad body of tidal water with one of the highest tidal ranges in the world (Uncles, 2010), with

an extreme tidal range of 14.8 metres (Allen, 1998). This estuarine environment is suitably

explained by Pritchard (1967). High tidal range and gradual action of waves and wind (Bird,

2008) are continuously acting upon this coastline and creating the variety of landforms

present; but the influence of high magnitude events are also taken into consideration

(Haslett, 2009) as a dominant factor in creating the features, and the potential issues present

at this macro-tidal coastline (Davies, 1964).

The wider study area within Bridgewater Bay is governed a Site of Special Scientific Interest

(SSSI) and designated under the Ramsar convention (Bowman, 1995) as a Special

Protection Area (SPA). Analysis of this investigation took place at a particular section of this

coastline; section C as demonstrated by figure 2. The geology and geomorphology present

at Berrow from the extensive beach and tidal flat deposits to windblown sand dune system

are shown in figure 4 (Spencer, 2013). This site has an important role to play in this coastal

zone; the Berrow sand dunes which extend up to 600 metres inland at their widest point (Pye

et al., 2007) provide an effective natural coastal defence. This dune system; notified an

SSSI under section 28 of the wildlife countryside act (1981), is an important geological

habitat and designated as a Local Nature Reserve (LNR), location of which is shown on

figure 2 (Sedgemoor, 2014). The dunes provide an environment for over 270 species of

flowering plant, giving the most diverse flora and fauna ecology on a local and on a national

scale (English Nature, 2011). The LNR is one of the best sites for moths and rare species

such as the pinion spotted pug moth have been recorded there and many other species

listed (Natural England, 2014). Hundreds of bird species also occupy these areas (RSPB,

2013) which are able to thrive here due to the defence the dunes provide from the hyper-tidal

estuary (Briggs, 1991).

The settlement of Berrow village is home to over a 1500 people, as well as the influx of

holiday makers who visit the beach and various tourist attractions the area has to offer

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

(Visit Somerset, 2014). The golf course, Holiday Park and other amenities (Burnham-on-Sea,

2014) create good economic revenue that the dunes at section C provide protection of.

Figure 3 shows the Somerset levels just inland of the dunes are up to 3 metres below high

spring water tide mark (Haslett, 1998), which demonstrates the vulnerability to inundation

and the protection the natural dunes are providing (Bardecki, 2008; Martinez, 2013). Behind

this lies the M5 motorway (figure 5) which is a significant transport route also threatened by

the possibility of Global Sea level rise (SLR). A coast should provide protection of habitat,

defence in terms of dissipating energy, and resource protection. When the coast no longer

fulfils the three roles then ‘Coastal Zone Management’ (CZM) (Beatley, 2002) needs to be

implemented (Image 1.1) to monitor and prevent the risk of flooding, sustain biodiversity and

to maintain environmental quality to provide better habitat in the coastal zone.

Image 1.1. Coastal zone management, from Conway (2003), adapted by author.

The area has a history of flooding with several events occurring between 1903 and 1981

giving multiproxy evidence of the potential risk (Burnham-on-Sea, 2006), further emphasizing

the importance of the natural dunes at this site. Currently the beach is a starved system as

outlined by Kirby (2010), limiting sediment supply to the dune system. In order for the dunes

to grow, supply of sand must be sufficient and sediment size must fall between the 0.2-2mm

in the intertidal zone with prevalent winds (UKBAP, 2010). The location has strong variant

wind speed (Uncles, 2010) blowing from the south west, sufficient enough for aeolian

processes detailed by Masslink & Hughes (2003) to occur if sediment supply is abundant; an

issue for this study site. The physical drivers of coastal change mentioned before are

projected to increase along with the likelihood of coastal inundation and erosion (Webster,

2005). Global SLR has risen 3.3mm yr-1 over the past 20 years (Boening, 2014) which

increases the threat of shoreline erosion, saltwater intrusion and general flood risk. A way of

counteracting the issue is through Integrated Coastal Zone Management (ICZM) outlined by

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

Van der Meulen et al., (2001). The Intergovernmental Panel on Climate Change (IPCC)

emphasize significant future environmental changes in sea level, ecosystems and the like

around the world (IPCC, 2007), and endorse ICZM to be a policy response to climate change

(Moksness, 2009). The problems associated with the study area and the possible

management techniques to resolve them are discussed in the following sections.

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

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Figure 1: location maps. Google maps: Edina Digi map: Edited by author

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

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Figure 2: Section C (Study site) Edina Digi map, edited by author/ LNR: Magic 2014) edited by author

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

Figure 3: Sedgemoor District Council/ green infrastructure study vol1.

Research report (2011) & Edina Digimap, edited by author.

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965Figure 4: Geology of Brean Down to Burnham-on-Sea, Edina Digimap (2014), edited by

author.

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 110209652. Coastal Problems

Fundamental to successful long-term sand dune habitat conservation and coastal zone

management is the understanding of geomorphological and ecological processes, and

human activities influencing dune characteristics past and present (Saye, 2007). The study

site demonstrates typical dune problems detailed below, as well as the probable future

without CZM. More sustainable approaches to coastal management policy rather than the

hard engineered defences (Clark, 1994) (Image 3.3), look to provide long term sustainability

to the coastline.

2.1 Regional Problems: Climate change/SLR

Climate change (Church, 2010) has and is expected to continue causing a profound series of

changes (Image 2.1) (Haslett, 2009). Coastal areas are the most densely populated,

economically active, and where the most productive ecosystems are found (Sachs et al.,

2001; Kremer et al., 2004), applicable to the study site. Global SLR (Image 2.2) has risen

between 1.8+ 0.3mm/year over a 50 year period (Church, 2010). The IPCC (2007) forecasts

between 8- 29 centimetres in eustatic SLR by 2020, not accounting for subsidence (Pethick,

1993), with further increase expected by 2100 (NSF 2014, image 2.3). The problem puts

pressure on the dunes especially in storm surge events by raising the plain from which

waves operate and decreasing return period which magnifies coastal erosion, avulsion and

flooding (Carter, 1991).

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

Image 2.1. Climate Change: Nicholls et al., 2007b, adapted by author.

The response of a shoreline to SLR describes the shift in sediment via transgressive dunes,

modified habitats and Coastal squeeze (Bruun, 1962).Coastal squeeze through denudation

(Doody, 2004) causes a net loss of sediment. Eustatic movements (Masslink, 2003), ocean

temperature (Halsett, 2009) and salinity, sedimentation, human influences, and the various

types of tectonic movement as outlined in Bird (2008) escalate the problem of SLR. Mean

SLR and tidal range directly influence beach width and morphology at the study site

(Houston et al., 2001).

Image 2.2: Global SLR, BBC (2014)

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

Image 2.3. Future SLR prediction, NSF 2014

2.2 Beach specific problems:

2.2.1 Sediment supply

Section C is a transitional zone between a river and the sea (Allen, 2011), receiving sediment

from fluvial and marine sources (Perillo, 1995) examples of which are detailed by King

(1972). Fluvial and marine sediment supply is sufficiently outlined by Bird (2008). Berrow

beach is constantly trying to achieve equilibrium (Masslink, 2003); however sediment in the

Bristol Channel has reduced overtime with the majority in suspended load or deposited on

the tidal flats creating a starved system (Kirby, 1986). Intertidal flats have become muddier,

with increased marsh which has reduced the sediment supply to the beach (Pye et al., 2007).

2.2.2 Car parking/Compaction

The area has the right conditions in terms of tide, wind, and profile for dunes to accumulate;

however the clayey/silt (Spencer, 2013) fine sediment on the beach face is not ideal for the

process of aeolian transport (Haslett, 2009). Popularity of Berrow sees an influx of tourists in

summer months and the impact of vehicles parking on the beach (image 2.4) increases sand

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965displacement, compaction (Schaler and Thompson, 2008), and is detrimental to macro-

invertebrates and faunal species (Stephenson, 1999; Martinez, 2013).

Image 2.4. Beach car parking. Google images

Compaction severity depends on sediment composition (Allen, 1999); at the study site

sediment is too cohesive for wind transport; the vehicles have compressed the sand

increasing water holding, causing a saturated foreshore (Image 2.5). The saturation is

affected by the high groundwater draining onto the foreshore at low tide (Davis, 1985),

reducing dry sediment for surface creep and saltation. The sediment budget (Bird, 2008) is at

a net loss as a result which directly limits the possibility of dune coupling.

Image 2.5. Saturated foreshore, taken by author

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

2.3 Dune specific

2.3.1 Sea buckthorn

Sea Buckthorn (Hippophae rhamnoides) detailed by Doody (2013) was introduced to Berrow

in 1982 to combat sand blow and encourage stabilisation of dunes (Richards, 2011), but the

permanent stability it provides is contradictory to natural dune function (Ritchie, 2001).

This invasive, non-native species quickly spread via rapid growth, altering soil composition

(Hodgkin, 1984) and displacement of native species such as Marram (Ammophila arenaria)

and Lyme grass (Leymus arenarius) (Binggeli et al., 1992). Sea Buckthorn threatens the

dune system through low tolerance to beach conditions; the roots are exposed to salt spray

and sand/wind blasting, subsequently deteriorating then washed away from the fore dunes

(Image 2.6) resulting in loss of dune sediment (Richards, 2011) especially in storm events.

The intolerance to coastal conditions initiates blowouts (Bate, 1996) and inundation.

Image 2.6 Foredune erosion, Taken by author

2.3.2 Footfall

Natural and anthropogenic disturbance to the study area have initiated the decline of dune

vegetation within the Berrow dunes due to extensive use of footpaths (Bird, 2008), causing

trampling and associated problems outlined by Lake (2010) and Coombes (2007). The

footpaths run perpendicular to the coastline (image 2.7) matching prevailing wind direction

and aiding deflation (Haslett, 2009). Once sediment is lost inland it cannot be regained. Zero 12

Sea Buckthorn eroded and exposing dune front

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

management will see accelerated erosion and denudation rates allowing for continued

windward deflation (Carter, 1990) and blowout formation (Bate, 1996) as shown in image 2.7;

the resultant loss of natural flood defensive will create the need for expensive hard

engineering techniques (Silvester, 1974).

2.3.3 Reed swamp

Behind the fore dunes at the study site a reed swamp has developed (Spencer, 2013) due to

the present peat conditions (Mullin, 2009). Characteristics of this freshwater swamp are

detailed by Bird (2008); the swamp is dominated by reeds (Phragmites communis) often with

rushes (Typha spp.) or sedges. This represents a stage in vegetation succession and the

processes mentioned above have narrowed the dune system in front of the reed swamp

(image 2.8), creating the risk of breaching in this area causing saltwater intrusion (Barlow,

2009) and the destruction of this sensitive habitat.

Missed opportunities are seen at the study site; the LNR have implemented a hold the line

programme, evidenced by small scale thatching and interpretation panels (Sedgemoor,

2014). A larger scale, more proactive approach is needed in order to see results. If zero CZM

was to be implemented to the study area the pressure of SLR (Church, 2010) would result in

inundation of a large area across the Somerset levels (Figure 5), destroying the economic

and social benefits previously mentioned. The following sections will outline the possible

management strategies to be rejected and the most appropriate ICZM for the study area.

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

14

Prevailing wind

Formation of a Blowout

Footpath across dunes to beach

Image 2.7 Footpaths through dune system: Taken by author & Google maps

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

Image 2.8 Reed Swamp: Google maps, amended by author15

Gap between reed swamp and potential breach

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

Figure 5: Potential future inundation: ArcGIS created by author & EA 2014.16

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

3. Management solutions to reject

This section considers the management options that are inappropriate for dealing with the

problems at the study site, identified in section 2. A conceptual framework for coastal

vulnerability assessment by Klein and Nicholls (1999) helps emphasise the best approaches

for any vulnerable coastal environment (Image 3.1). Standing Conference on Problems

Associated with the Coastline (SCOPAC) detailed by Haslett (2009) and Hook & Bray (1995)

was created to implement CZM through governing bodies such as district councils. Table 1-5

summarise whether the management techniques ‘tick or cross’ the 4 fundamental categories

for successful coastal management at the study site.

Image 3.1: Conceptual framework of Coastal vulnerability. Klein & Nicholls (1999), edited by

author.

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

3.1 Do nothing/zero management:

Table 1.

Defence: X

Habitat: X

Resource: X

£: X

A do nothing approach at this site is already discounted considering the problems previously

outlined and the various habitat, settlement and assets (Burnham-on-sea, 2014) at the study

site (see Section 1), and the awareness that the dune system is under a lot of pressure

because of SLR (Church, 2010). The dunes have visible damage to the forefront from recent

storm surges (image 2.6) and sediment supply issues will see a continued net loss of the

dunes. Eventually hard engineering techniques will have to be implemented to prevent

flooding, coming at great monetary expense (SNH, 2000). This management scheme

achieves none of the fundamental issues as shown in table 1 and so can be rejected.

3.2 Managed retreat/realignment:

Table 2.

Defence: X

Habitat: X

Resource: X

£: X

This management technique involves the relocation of communities and industry (Masslink,

2003) in order to let areas of hinterland to be claimed by the sea. The Somerset levels are

below mean sea level (figure 3) which forces an all or nothing approach in this area; either

defend a hard line on the map (French, 2002), or allow an area to be inundated. The range of

habitat (Sedgmoor, 2014), settlement and resources (Burnham-on-Sea, 2014) along the

Burnham coast (section 2) have been deemed significant enough for a hold the line

approach (Image 3.2) to have already been implemented by the Environment agency (EA,

2014). Hard defences have been used (image 3.3) which provides a fixed line of defence

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965(French, 2002) from SLR and inundation. Managed retreat can therefore be rejected as a

management concept because it cannot be implemented alongside the already established

techniques on the Brean Down - Burnham-on-Sea coastline without making them void

structures. Strong government supported legislation (Haslett, 2009) that is needed for this

type of management is not present for the study site. It does not achieve any of the

fundamentals (table 2) and cannot address the problems outlined in section 2.

3.3 Accommodate:

Table 3.

Defence: X

Habitat: X

Resource: X

£: X

This management solution involves adapting to and living with SLR and inundation through

the elevation of buildings and modifying drainage systems (Haslett, 2009). It requires

significant organisation and community participation, as well as funding to adapt the entire

infrastructure already in place (Hook & Bray, 1995). Due to the low lying nature of the land

behind the dune system this management scheme is not suitable as it would cause social

and economic loss and undermine the current management strategies implemented by the

EA (2014). This is because accommodating SLR does not conform to the hold the line/hard

engineering techniques (image 3.3) that have been put in place further up the coast. On

these grounds it is possible to reject this strategy.

.

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 110209653.4 Protection/Hold the line:

Table 4.

Hard engineering: Sea walls, rock

armour, revetments, Groynes,

gabions

Soft engineering: beach nourishment,

fencing, vegetation planting

Defence:

Habitat: X

Resource: X

£: X £200-500/100m

This hold the line approach physically protects the coastline through hard or soft engineering

(Masslink & Hughes, 2003).Sea walls and revetments provide an instantaneous barrier

against the threat flood inundation as seen further up the coastline from the study site (Image

3.3). However, hard engineering is hugely expensive and causes environmental problems,

specifically wave reflection and accelerated erosion (Kraus & McDougal, 1996). Table 3

emphasizes the detrimental effect hard engineering has on habitat and resource. The ‘fixed

line’ (SNH, 2000) causes a barrier between marine and terrestrial zones which disrupts

natural dune beach processes (Dugan et al., 2008) proving costly for the valuable habitat.

Groynes (Nordtsrom, 2014) act against longshore drift (LSD) causing starvation down drift

(Peterson et al., 2000a). They do not conform to the known geomorphology outlined in

section 2 as LSD is absent from this estuarine environment. Hard engineering increases

erosion rates by reflecting wave energy on the beach and dunes (Masslink & Hughes, 2003).

They disrupt public access to the upper beach and can be seen as an eye sore (SNH, 2000).

A storm in 1981 (Lewis, 2010) caused overtopping (Ingram, 2009) of the sea wall at

Burnham-on-Sea (Smith, 2009) causing flood damage to nearby towns (Burnham-on-Sea,

2006). The dunes system at the study site however, dissipated the storm energy effectively

protecting the hinterland from inundation. Soft engineering may be the most suited

management option (table 4) at the study site. On the above evidence hard engineering is

rejected as a management technique.

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 110209653.5 Advance the line/ Offshore structures

Table 5.

Defence:

Habitat:

Resource: X

£:

The current environment between Brean Down and Burham-on-Sea is a struggling dune and

beach system with an ever decreasing sediment budget (see section 2). With much of the

sediment supply suspended in the tidal flow the area lends itself for saltmarsh creation, much

like the sand bay coastline just north of Brean Down (Visit Somerset, 2014). The

implementation of an offshore defence (Lamberti et al., 2005) will reduce the tidal energy and

increase the scale of deposition resulting in saltmarsh formation overtime. This will overall

increase species diversity (Martin et al, 2005) whilst forming a natural coastal defence, but

will replace the sandy beach/ dune habitat with a marsh environment (Nordstrom, 2014). The

maintenance of the dunes and beach is vital due to the tourism it attracts and flood defence it

provides, allowing for the rejection of this management scheme.

Image 3.2: EA 2013

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Image 3.3 Existing coastal defences: Edina Digi map, photos taken by author.

22

Sand dunes at Study site

Ad hoc defence

Hard engineering

Rock armour

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 110209654. Recommended management

Preparation of a suitable CZM plan that ensures the conservation and sustainable use of

dune systems requires analysis of the impacts of sea level, climate, human activities and

sediment supply in the dune systems (section 2) (Saye et al., 2007). The geomorphological

response of Berrow Dunes (figure 2) to these implications help shape a future ICZM strategy

for the area. In order to provide a solution to the problems outlined in section 2 the following

management strategies are to be implemented:

i. Removal of sea buckthorn

ii. Dune vegetation (native species) planting

iii. Dune fencing implementation, and managing people

iv. Car parking initiative

Sea buckthorn

removal

Planting native

vegetation

Fencing Car parking

zones

Beach

nourishment

Defence

Habitat

Resource

£ x

v. Beach nourishment to encourage dune coupling

Table 6.

i. The problem with Sea buckthorn at the study site as outlined in section 2 is its invasive

nature causing reduction in native Marram and Lyme grass (Binggeli et al., 1992). This soft

engineering technique (Haslett, 2009), will strategically remove the sea buckthorn from

inland dunes to the fore dunes over a 3 year timescale (Figure 4.1). Cutting and burning will

take place between October and February each year in the designated areas, followed by re-

spraying to kill regrowth in the following spring months (ESCC, 2014). Removing the

invasive species alone will result in further net loss of sediment (See section 2.) so the

chosen strategies (i & ii) must work in tandem with one another in order to improve

sediment accumulation and the natural function of the dune system (Broome, 1981) (Figure

4.1 and 4.3). Sea buckthorn creates a contradictory environment to natural dune function

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965(Ritchie, 2001), so the removal of this shrub whilst planting native species (ii) will help

recreate a naturally progressive system that provides a stronger defence to flood inundation.

This process is low cost as the sandy soil makes for easy plant removal; the labour intensive

nature being the only monetary spending (SNH, 2000). The golf course is worked into the

strategy, as there is evidence this man made area has been managed logically with native

vegetation and a managed water table so as not to hinder the dune system.

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

Image 4.1. Sea Buckthorn removal plan: Google maps, edited by author

ii. Once the invasive species has been removed from an area (image 4.1) dune grass planting

will take place. Vegetation traps sand, provides habitat and has aesthetic appeal (Hesp,

1989) whilst stabilizing surface sediment for other species to establish themselves (Martinez,

2004). Many aspects must be considered when planting dune vegetation outlined by Ranwell 25

Year 1 Sea Buckthorn removal

Year 2 Sea Buckthorn removal

Year 3 Sea Buckthorn removal

Golf course

Reed swamp

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965and Boar (1968). Wild thyme and marram grass will be used as it enhances the development

of yellow dunes above wave attack limit. This will be the first species undergoing planting

particularly in year 1 and 2 (Image 4.3), followed by Lyme grass in year 3 and beyond. Lyme

grass species help develop foredune growth because of its tolerance to inundation events

(SNH, 2000). Certain Species can be sourced from nearby areas of affluent growth

(image4.2) which further reduces the low cost scheme. Details of correct planting (image 4.2)

techniques such as plant root depth and spacing are detailed by Doody (2013). Initially plants

will be sown parallel to the prevailing wind to allow some wind to pass through and prevent

them being blown away completely at seedling stage (Tsuriell, 1974). Sand trapping is a

gradual rather than an overnight solution so a 3 year scheme will be used to assess

accumulation rates.

Image 4.2 Vegetation planting, SNH (2012)

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

Image 4.3 Vegetation planting zones: Google maps, edited by author

iii. Dune fencing is a management technique that will encourage the deposition of windblown

sand by interrupting and reducing wind speed, allowing foredune growth and resistance

against erosion (SNH, 2000). They are effective in reducing the damage seen from trampling 27

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965(Coombes, 2007), and protecting new or existing vegetation through managing the areas

accessible to tourists (section 2). The use of board walks and signs in conjunction with

fences to manage pedestrian traffic (Nordstrom, 2014) further enhance the effectiveness of

this technique (image 4.4), with the possible implantation of zigzag pathways (Snyder &

Pinet, 1981).

The success of this management idea depends on the void/solid ratio of fence posts, the

availability of blown sand and the amount of vegetation to stabilise the accumulating sand.

CERC (1984) recommend straight fences parallel to the coast with porosity of 50%

preferably coinciding with natural dune vegetation. Strategies (i.) and (ii.) will provide

sufficient vegetation upon the dunes and strategy (iv.) will reduce compaction and increase

sediment available for beach dune coupling.

Chestnut paling fencing costs £400-2000/100m with approx. 2-5 years life expectancy (SNH,

2000). Low cost, good life span and ease of erection makes it ideal for the study site and

outweigh the problems associated with this technique e.g. beach litter. Fencing will be placed

across the entire study site in year 1 for immediate dune and reed swamp protection, and

subject to rate of sediment accumulation, a second fence line behind it in year 2 or 3 (Image

4.4 & 4.6). Forecast sand accumulation averages about 1m³/ per meter of fence per year

(Davis, 1985), so a three year projection looks positive for beach dune coupling and

increased sediment budget.

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Image 4.4 Dune fencing plan: Google maps, edited by author

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

Image 4.5 Frontal dune defence SNH 2012, edited by author

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

Image 4.6 Dune fencing: South West Coastal Group

iv. Car parking on the Berrow beach causes issues of compaction and interferes with the natural

processes of sediment transport from beach to dune as detailed in section 2. Ideally there

would be no parking on the beach but the areas popularity will not allow for this. As an

alternative, parking will be restricted to particular sections along the beach (Nordstrom, 2003)

through signage and boundaries to manage pedestrian traffic (Nordstrom, 2014). A rotational

scheme is forecasted by which 3 zones of parking systematically facilitate vehicles one zone

at a time interchanging each month (Image 4.7). The parking areas not in use will be

ploughed or raked (Dean, 2002) to loosen compacted sediment. This will assist the ease in

which aeolian transport (Haslett, 2009) and other beach processes occurring leading to dune

recovery. Beach raking can be detrimental to backshore habitats (Martinez, 2013) so will be

used strategically. This parking scheme is key to the success of the management scheme as

the other methods will fail without improved sediment supply. Beach nourishment (Spybroek 31

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

et al., 2006) is a viable option if current conditions remain the same and will be factored into

the 3 year plan for back up purposes (table 7).

Image 4.7 Car parking scheme: Google maps, edited by author

32

Zone 1

Zone 2

Zone 3

Page 34: Coastal Management Report, 11020965 (1)

Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965Management programme:

Year 1 Year 2 Year 3

i. Removal of sea buckthorn

Removal or invasive species from furthest

shoreward zone (image 4.1), via cutting,

burning and spraying.

Second zone closer to

shoreline removed through the

same techniques (image 4.1)

Final near shore zone removed

of invasive species.

Monitoring progress Check species is not returning after each year of removal.

ii. Native vegetation planting

Planting to occur in shoreward zone (image

4.3), immediately after removal of sea

buckthorn to reduce deflation rates. Marram

grass and wild thyme planted in year 1.

Primary planting behind fencing in

nearshore zone (image 4.2).

Repeat planting in next

designated zone (image 4.3)

predominantly Marram grass.

Planting of Marram and Lyme

grass in the near-shore zone to

encourage embryo dune

growth.

Monitoring progress Monitor rate of vegetation growth, and assess whether more planting is needed.

iii. Dune fencing implementation, and managing people

Introduce fencing along entire study site to

provide protection to reed swamp and

vulnerable areas. (Image 4.4) primary

planting of Lyme and marram grass behind

fence (image 4.5).

Check accumulation rates

behind fencing, and make sure

pathways are fenced, with

signage for visitor guidance.

Continue maintenance of

fencing whilst checking

accumulation rates. If

appropriate, erect a second line

of fencing (image 4.4 & 4.6).

33

Page 35: Coastal Management Report, 11020965 (1)

Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965Monitoring progress Maintenance of fences and monitoring of accumulation rate yearly.

iv. Car parking scheme

Signs/ boundaries enforced (image 4.7) for

visitor parking guidance. 4 week rotational

scheme and beach raking commences.

4 week rotation maintained,

unused zones to be raked

every 4 weeks. Check

sediment accumulation in front

fences.

4 week rotation scheme

continued, with monthly beach

raking.

Monitoring progress Check parking is occurring in designated zones only. Assess the effectiveness of rotating the zones in peak

summer months.

Assessment after 3 year programme

Monitor beach and dune height; check fenced areas for accumulation rates to assess if sediment supply is

increasing. Beach nourishment may be implemented after the 3 year programme to improve sediment supply.

34

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Management of Rivers and Coasts (UBGMXD- 20-3) Student number: 11020965

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