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Feature
27th Oct 2011Posted in: Feature Comments Off on Our Coastline
Our Coastline

A description of the South East Coastal Group’s coastline

The shoreline covered by the South Downs Coastal Group spans some 300km of Kent, East and West Sussex, on the south coast of England.  Along this coast are several types of natural and manmade features; many of which are shown below in a fly-over of the coastline. For more detailed information management of these sections see management boundaries and policy units for the SMP. 

Medway Council

This section of coastline managed by Medway Council on the Isle of Grain covers All Hallows firing range to Grain Power Station.  This section of coastline is mainly defended by a concrete seawall fronted by a narrow sand and shell beach with a deep mud foreshore. The exception is a short section of soft cliff that is defended by concrete block structures. Timber groynes front the revetment at All Hallows Holiday Park. Parts of this frontage are designated as part of the Thames Estuary Special Protection Area (SPA).

Swale District Council

The Isle of Sheppey is managed by Swale Borough Council, and can be split into four main sections of coastline.  The coast at Sheerness is a heavily defended shingle beach with timber groynes, rock revetment and prominent seawall.  Warden Bay is designated as a Site of Special Scientific Interest (SSSI) consisting of undefended soft cliffs that are actively eroding. Leysdown is fronted by a flat sandy beach, with timber groynes and a large seawall along much of its length.  Shell Ness consists of a private shell beach with a variety of privately-constructed defences, south of which is an area of undefended saltmarsh and mudflat habitats, designated under the Swale SPA. 

Canterbury City Council

The north Kent coastline between Castle Coote and Reculver Towers is managed by Canterbury City Council and (in parts) the Environment Agency.  The whole frontage is heavily defended by a combination of timber groynes and various designs of seawall.  However, there is also a short section of actively eroding soft cliffs around Bishopstone Glen. This coastline also includes Whitstable Harbour, one of the main fishing harbours in the south east.  In addition, SSSI, Ramsar and SPA designations are all present along this frontage.  There are several unique features along this frontage; including a shingle bar which is perpendicular to the shoreline at Tankerton and the offshore bank at Seasalter (below).

Thanet District Council

The Thanet District Council coastline covers Northern Sea Wall to Pegwell Bay. Northern Sea Wall is a 5km stretch of heavily defended shingle beach held by rock groynes and backed by a concrete sea wall, and managed by the Environment Agency.  The rest of Thanet coastline is defined by its pocket beaches and chalk and sandstone cliffs. The main towns of the district are defended by a seawall and promenade, as are some sections of cliff line. These alternate with undefended sections. Ramsgate Harbour is a main route into Britain for freight, as well as being a popular leisure harbour.  Parts of the Thanet frontage are designated as SSSI, Special Area of Conservation (SAC), Ramsar and SPA. Below, the image shows Bottany Bay; one of the bays in the Thanet District.

Dover District Council

Dover District Council manages the coastline between Sandwich Bay and The Warren.  A range of stakeholders, such as the Environment Agency, Dover Harbour and Network Rail work closely with this stretch of coastline.  Sandwich Bay is unlike neighbouring beaches due to its extensive, undefended, sand dune system and prograding spit at the mouth of the River Stour.  Deal is defended by a coarse shingle beach; timber groynes and a seawall ensure the beach is kept to a suitable level to protect the town and historic castles behind.  The coastline between Kingsdown and The Warren is mainly undefended cliff with a small beach.  Dover Harbour is built on reclaimed land at the base of the cliffs, providing one of the main routes into Britain for passengers and freight.  Parts of this frontage are designated as SSSI, SAC, and Ramsar.

Shepway District Council

Shepway District Council is responsible for the coastline between Copt Point and Lydd Ranges.  East of Folkestone Harbour is a wide sandy beach, backed by a series of concrete arches to protect the cliffs from eroding.  Hythe to Folkestone Harbour is heavily defended by a shingle beach which undergoes bi-annual recycling following the 2004 Hythe to Folkestone coast protection scheme, which introduced 360,000m3 of shingle and additional rock groynes.  Dymchurch to Littlestone is protected by a combination of timber groynes and a new concrete seawall to ensure the low-lying Romney and Walland marshes are protected from flooding. Littlestone to Dungeness is fronted by a shingle beach which is considerably steeper towards Dungeness. The beach changes from predominantly shingle to sand at Lydd Ranges where the beach consists of a large sandy foreshore and dune formations through to Camber Sands.  Notably, large sections of this coastline are designated as SSSI, Site of Nature Conservation Interest (SNCI), National Nature Reserve (NNR), Ramsar and SAC.

Rother District Council

Rother covers Camber Sands to Pevensey Bay – but does not incorporate Fairlight Glen to Bulverhythe (managed by Hastings Borough Council).  Winchelsea Beach has recently (2009) undergone a capital scheme providing a 200-year standard of protection.  This includes additional groynes, shingle recharge and the construction of a secondary defence flood bund and gabion wall.  Fairlight Cove is characterised by rapidly eroding soft cliffs and is largely undefended apart from a 250m rock revetment. The image belows shows Fairlight looking east.

The Bexhill coastline consists of a shingle beach maintained by a series of timber groynes which leads (west) into Pevensey. Pevensey Coastal Defence Ltd was formed specifically to provide flood defence services at Pevensey Bay for the Environment Agency, who manage this stretch of coastline on behalf of Wealden District Council.  Pevensey Bay’s sea defences are no longer self-sustaining, and they have to be managed to ensure that the required level of protection is provided.  This involves regular recycling and reprofiling of the beach to ensure it meets high protection standards.  Parts of this frontage are designated as SSSI, SAC, SPA, and Ramsar.

Hastings Borough Council

Hastings BC manages the coast from Fairlight Glen to Bulverhythe.  Fairlight Glen is an area of undefended cliffs of international environmental, geological and ornithological importance, with high landscape value, and no significant cliff top developments.  Hastings is a dense urban area that is developed to the edge of the low coastal slope and fronted by a shingle beach of amenity and tourism importance. Bulverhythe is a largely low-lying developed frontage backed by the Combe Haven Valley, which is of environmental importance. To prevent flooding of the extensive coastal developments, a rock revetment and several rock groynes were constructed in 2009.  Parts of this frontage are designated as SAC and SSSI.

Eastbourne Borough Council

Sovereign Harbour to Beachy Head falls under the management of Eastbourne Borough Council.  Sovereign Harbour is a major marina development extending to the beach edge, within a flood risk area.  In 2011, a capital scheme was implemented along the frontage at Eastbourne to increase the level of coastal protection.  The frontage is heavily defended with a concrete seawall, a substantial shingle beach, and timber groynes.  Beachy Head is an undefended landmark area designated as an Area of Outstanding Natural Beauty (AONB), a Heritage Coast and a SSSI. 

A recent massive rock fall can be seen in the foreground of the image overlooking Beachy Head. Little active management is undertaken; there is no development at the cliff top and the gradual but continual loss of material is seen as a natural process that should continue. There is some benefit to coastal processes from cliff falls in the area, not from the chalk that temporarily accumulates at the foot of the cliff but more from the flint that is often contained within the chalk. The flint lasts longer in the system than chalk as this quickly degrades and dissolves.

 Wealden District Council

Wealden District Council are responsible for a small section of coastline at Pevensey, however this is managed by PCDL (Pevensey Coastal Defence Limited).  The other section under Wealden DC covers Birling Gap to Cuckmere Haven, which incorporates part of the Seven Sisters and the South Downs.

The image below shows Birling Gap, where the high chalk cliffs of the South Downs meet the sea at the eastern end of the frontage, an old dry river channel presents a weaker defence than the surrounding chalk cliffs.  This results in increased erosion and has caused controversy as to whether there should be human intervention to safeguard the small number of properties on the cliff-top or should the natural process of cliff recession continue to safeguard the Site of Special Scientific Interest.  Unfortunately for those living on or near the cliff-top, economic considerations also come into play; the benefit of defending the coast must be weighed against the cost, now and in the future, of providing a defence. This is true of the whole coastline.

Lewes District Council

Lewes DC includes the coastline between Cuckmere Haven and Saltdean.  A number of rivers discharge to the sea along the frontage; notably the Cuckmere at Exceat where the artificial cut made in 1846, the disconnected meanders can be seen in the foreground of the image below.  This area is more natural so sustainable defence can be established; controlled breaches are to be formed in the banks and areas of pasture allowed to flood and revert to floodplain.  The meanders may also later be re-established by reconnection to the main channel. In the middle of the frame is Seaford Head and a little further west is the town of Seaford.

The second image (below) look eastwards at the port of Newhaven is on the River Ouse. The main port operation is a cross-channel ferry to Dieppe and the approaches are regularly dredged to allow these ships to operate.  Seaford is at the top of the frame and Peacehaven, in the foreground, is on the Greenwich Meridian (0° longitude). Seaford has a wide shingle bank, regularly recycled by the Environment Agency, to provide a defence against the prevailing south-westerly storms which attack with great force.  Whilst the area to the east of the Ouse is low lying, the land to the west is relatively high and continues to be so through to Brighton – a distance of approximately 13km.  There are few defences along the eastern part of this shoreline, although to the west the undercliff is protected by a concrete seawall and several rock and masonry groynes.

Brighton & Hove City Council

The Brighton and Hove coastline covers the 13km between Rottingdean and Portslade-by-Sea.  In the foreground of the image below, shows Rottingdean and towards the top of the shot is Brighton Marina.  The coastal plain beyond Brighton rarely rises more than 10m above Mean High Water near the shoreline. Much of Brighton is fronted by a wide shingle bank, especially the area immediately west of the Marina. There are a number of large masonry groynes in the main beach and these generally give way to more traditional timber groynes in the west.  The coastline was protected by ad hoc defences in the 1800s; prior to this the coast was typically eroding by as much as 2½m per year. With the increase in development in the 1920s & 30s came a more concerted effort to defend the coast against erosion.

Brighton Marina (below) was constructed in the open sea, from precast concrete caissons sunk to the seabed, in the early 1970s. The Marina now supports high quality residential property and various retail and leisure units. It has a large pleasure craft mooring facility; fishing and dive boats also operate out of the Marina.  Approximately 7km further west Shoreham Harbour supports a more commercial operation, with timber and aggregate ships regularly discharging their cargoes. This commercial operation exists alongside a smaller pleasure sailing fleet.  The locked harbour is on a spur of the River Adur, which is controlled by two harbour arms. Shingle builds against the western arm and material is by-passed eastwards to help reinforce the narrow, timber groyned beach fronting the Harbour.

Worthing & Adur District Council

Worthing and Adur councils have recently merged to cover the coastline between Portslade-by-Sea and Ferring (east); a coastal stretch of 15.7km.  The beach is protected by a shingle beach and evenly spaced rock groynes.  The east is defined by its shingle beach and rock groynes, backed by the River Arun mouth and the lagoons, and the west is heavily defended by timber groynes and concrete seawalls, backed by compact developments. The image below was taken above South Lancing; looking east over the lagoon towards Shoreham-by-Sea.  

To the west of the frontage the inter-tidal area and the seabed beyond slope very gently, producing a wide (up to 500m) foreshore, much of which is covered with a veneer of sand over the chalk bedrock. Beyond Bognor Regis (Arun DC) this chalk gives way to London Clay, interspersed with Reading Beds (shingle) and harder sandstone outcrops.

Arun District Council

Arun DC boundaries are defined by Ferring in the east and Pagham Harbour at the west.  Pagham Lagoon used to be the outlet to Pagham Harbour in the late 1800s and was formed when the migration of the shingle spits sealed the outfall to the sea. Towards the east is Climping (at the end of the Elmer scheme) which can be seen in the image below; giving way to the largely open beach which fronts the strategic gap between the conurbations of Littlehampton and Bognor Regis.  High quality farmland is a key feature of the coastal plain in the west of the area.

Rock has been used in an number of innovative project as in the scheme seen here at Elmer. The old timber groynes were unable to efficiently maintain a suitably wide shingle beach, due to the increased sediment transport rates caused by the change in beach plan shape.

The rock breakwaters reduce wave energy whilst allowing some littoral drift to continue. The scheme was a joint project between the local authority and the national Rivers Authority (Now Environment Agency) and cost around £6m, in a number of phases. The main one being constructed in 1992/93 and involving 200,000 cubic metres of imported shingle and 100,000t of rock.

Aldwick Bay, in the foreground (below), has a naturally accreting beach giving way further east to the timber groyned beaches of Bognor Regis, Felpham and Middleton.  Many of the defences fell into disrepair during WWII and it was not until the introduction of the Coast Protection Act in 1949 that many coastal defence systems were again brought back into good order.  Today, where appropriate, the “hard” defences of concrete seawall and timber breastworks are being replaced with the “soft engineering” of shingle beach management systems and rock structures.  Whilst the rock used is in itself hard, the defence systems constructed with it and the wider shingle beaches are considered “soft” because they absorb wave energy, rather than reflecting it with seawalls, as in the past. Wave reflections encourage scour to occur and thus remove beach material from the shoreline.

Lastly, Pagham Lagoon; the spit which fronts the lagoon is increasingly migrating eastwards and further enclosing the mouth of the harbour. The image below shows the spit from the west, with the Selsey Bill in the background.

Chichester District Council

Selsey Bill is a Site of Special Scientific Interest, Special Area of Conservation, Special Protection Area and a Ramsar site. It is an important site for nesting Terns and the shingle ridges support colonies of Yellow Horned Poppy and Childing Pink.

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