113 - North Kent Plain : Description

Physical and functional links to other National Character Areas

The North Downs are to the south of this National Character Area (NCA) and form a distinctive backdrop, with the boundary delineated between the Chalk and the Eocene deposits (although some Chalk also outcrops at Thanet). The underlying Chalk aquifer (an important source of groundwater abstraction) creates a functional link to surrounding NCAs. To the north is the alluvial Greater Thames Estuary. The area’s western boundary is defined by Inner London and the Thames Basin Lowlands.

The River Darent drains from springs in the Wealden Greensand through the North Downs, and then runs through the western part of the NCA and north into the Thames. The Medway and Stour rivers drain north through the North Downs into the NCA, the Medway running north into the sea via the Greater Thames Estuary and the Stour flowing east directly into the North Sea.

Coastal processes of sedimentation and erosion provide a functional link between this NCA and, for example, the Greater Thames Estuary NCA to the west and the North Downs NCA to the south: as such, management of the coastal frontages cannot be considered in isolation. There are differences in the coastal processes on either side of the North Foreland: the moderately strong tidal streams ensure that the sand deposits are quite mobile.

The North Kent Plain NCA is an important transport corridor, with major rail and road links connecting Kent’s coastal towns with London. These (and the area’s proximity to the capital) have resulted in numerous economic, cultural and functional links with the City of London.

Distinct areas

• Thanet

The North Kent Plain today

Lying mainly on fine loam soils, the North Kent Plain is a productive agricultural area of England. With a generally low, gently undulating landform, the landscape is characterised by large, exposed arable and horticultural fields with regular patterns and rectangular shapes. These are predominantly devoid of hedgerows, and there is only limited shelter-belt planting around settlements, farmsteads, orchards and horticultural crops.

The west of the NCA is heavily urbanised, with large settlements and urban infrastructure dominant within the landscape. The proximity of the NCA to the coastal estuaries, marshes and heavy industry which characterise the area to the north has an influence on the NCA. Within and surrounding major towns, areas of green space provide a resource for local communities, including river corridors, woodlands and amenity greenspace. The Hoo Peninsula has a distinctive character and shelters the River Medway, forming a buffer and distinctive landscape setting for urban Medway. The wide ridge at the core of the peninsula is a solid backbone flanked by vast open grazing marshes to the west and the more secluded wetlands of Yantlet Creek to the east which both sit within the Greater Thames Estuary NCA.

The built environment also exerts a strong influence on the open farmland character, with associated infrastructure such as pylons dominating in expansive vistas. Discrete but significant areas of woodland provide contrast on the higher ground around Blean and to the west including Chattenden and Shorne, while the River Stour and its numerous tributaries are important features of eastern areas as they drain eastwards into the North Sea. There are a variety of coastal habitats, with many internationally designated for their biodiversity interest. The coast is an important resource for tourism and recreation.

The area’s geology is dominated by Palaeogene clays and sands, underlain by chalk that outcrops principally in Thanet which forms a discrete and distinct area of the NCA. The Thanet plateau is characterised by its unity of land use arising from the high-quality fertile loams. Open, with few trees, the area is dominated by wide views over an extensive land cover of cereals, root crops and other horticultural crops.

The extensive woodlands that comprise the Blean complex are designated as a Special Area of Conservation (SAC) for sub-Atlantic and medio-European oak or oak-hornbeam forests. This type of woodland is rare in the UK occurring only in the south of England (SAC Selection Data, Joint Nature Conservation Committee). The Blean complex is an important site for the rare heath fritillary butterfly, and supports a population of national significance. The woodlands further west are also of conservation value, while poplar and alder shelterbelts and small woodlands are characteristic in the east of the NCA. These are often associated with the locally distinctive land use of orchards and horticultural crops that characterise the area, and reinforce Kent’s reputation as the Garden of England. Although the area is predominantly arable, surviving wetland habitats within the Stour valley support a diversity of wildlife and include areas of grazing marsh, reedbeds, lagoons and gravel pits.

Elsewhere, fragments of unimproved grassland support a range of uncommon plants, including those associated with woodland on clay and sandy soils, and chalk grassland in Dartford, Gravesend and Thanet. A fine example is found at Queendown Warren (designated as an SAC for its grassland community), which supports an assemblage of rare orchids. A range of semi-natural habitats are also found along the coast.

A number of sites within the NCA are internationally designated for habitats and species associated with coastal systems (At the time of publication, a proposed new SAC (Tankerton Slopes and Swalecliffe) was in progress for Fisher’s estuarine moth): Sandwich Bay SAC for extensive dune systems, and the Thanet Coast SAC for chalk reefs and submerged (or partially submerged) sea caves. Thanet Coast and Sandwich Bay are also designated as a Ramsar site, reflecting the wetland invertebrates and winter populations of ruddy turnstone that they support. In addition, five Special Protection Area (SPA) designations fall either wholly or partially within the NCA, each relating to wintering, breeding or passage bird populations. Stodmarsh is a National Nature Reserve (NNR), designated as an SAC, SPA and Ramsar reflecting the bird and invertebrate interest.

Large settlements dominate within the landscape, notably in the west around Greater London and the Medway Towns; further east at Canterbury, Faversham and Sittingbourne; and along the hinterland. The rural settlement pattern predominantly consists of nucleated villages with low densities of dispersed settlement, while medieval prosperity is reflected in the buildings of small market towns such as Fordwich and Sandwich. Coastal towns such as Margate provide a reminder of past bustling British seaside resorts and still hold a traditional seaside appeal.

The NCA has a rich variety of heritage assets, both above and below ground. Notable are the Lower Palaeolithic skull pieces found at Swanscombe. Roman remains are found across the area and include the Saxon Shore forts at Richborough and Reculver, and the walled city and cathedral at Canterbury (a World Heritage Site). Watling Street Roman road is also a feature, still influencing road patterns. The lesser north-south pattern of minor roads is also notable and reflects the historic settlement pattern: many of these had their origins as Saxon drove roads, for the movement of pigs. Other historic elements within the landscape include iron-age, Anglo-Saxon and medieval sites, and the influence of arable farming on field patterns from at least the Iron Age – in addition to military remains along the coast, historic parks and gardens, and the historic naval dockyards of Chatham.

The landscape through time

Beneath the exposed geology of the North Kent Plain are Carboniferous strata – hidden Coal Measures – consisting of fluvio-deltaic sediments interbedded with seams of coal. These are not exposed at the surface, but they influence the NCA’s character, landscape, industry and historic environment. The Chalk above the Coal Measures was laid down in warm, shallow seawater, and then folded and raised above sea level by the effects of the Alpine Orogeny (mountain-building episode), and subsequently eroded. As sea levels raised, the shallow marine and estuarine sands and clays of the Thanet Formation and Lambeth Group Woolwich, Reading and Blackheath Beds, were deposited over the Chalk. As the sea deepened further, the London Clay was laid down. Further environmental changes have now raised these strata above the current sea level. The Chalk now outcrops in Thanet (originally an island separated from mainland Kent by the Wantsum Channel) and, to a lesser extent, it is also exposed in sea cliffs and inland quarries near the Medway Towns and Gravesend. Swanscombe Skull SSSI contains some of the earliest human bones found in the UK.

Although this area was not glaciated during the ice ages, severe erosion of the Chalk and Tertiary strata created superficial deposits of chalk and flint rubble (known as Head deposits), windblown sand, loess and various river gravels associated with the changing course of the Stour and other rivers. These have resulted in a predominance of highly fertile and easily worked soils, making it one of the most productive agricultural areas in Kent.

Arable farming has been important in the area since at least the Iron Age, with a high proportion of arable land – especially to the west and on Thanet. The area experienced only minor contraction in the extent of arable in the 15th century, when many other arable areas saw a shift to pastoral farming due to the proximity of the London market. For the same reason, fruit growing has been a major feature of the area since the 13th century, and increasing from the 17th century with the establishment of larger orchards. Market gardening was brought to the area around Sandwich by Dutch émigrés, and is now a characteristic feature of this area and of Thanet. The River Medway has had a major influence on the area, with its long maritime history. The brick-earth of north Kent is, as the name suggests, excellent for brick-making; this was an important industry, especially in the housing boom years of the early 19th century.

Grazing marshes once occupied almost all of the low-lying land of the lower Stour valley and Wantsum Channel, and south to Deal. Most have been drained and converted to arable farmland since the 1940s, although fragments of wetland habitat survive and the area as a whole attracts large bird populations. Other wetland habitats within the Stour valley have developed through coal-mining subsidence and gravel extraction. The area had been largely cleared of woodland by the 11th century: it is now confined to small blocks and copses – often on higher ground – and shelterbelts of poplars that protect orchards and soft fruit. The only significant areas of ancient woodland are confined to pockets of higher ground with acidic clay soils, such as around Shorne, Chattenden and, in particular, the Blean.

Coastal processes have played a significant role in the development of the NCA. This is well illustrated by the closure of the Wantsum Channel, a former tidal channel between North and East Kent which separated Thanet from the mainland until some 500 years ago. In 1953, the area was hit by extreme floods, due to a storm surge. This was devastating and was the trigger for most of the coastal erosion and flood defence works around the coastline. The proximity of the Thames Estuary has influenced the character of the NCA, with the Medway and Thames rivers both serving as major transport routes and supporting a range of industrial activities.

Rural settlement consists of a mixture of both small nucleated villages and dispersed farmsteads at low densities, villages being more of a feature to the east. Significant expansion of settlement has occurred in the area during the 20th century: these settlements originally grew up around farming and fishing communities, before they later (from the 16th century) became important naval ports and commercial centres. More recently, they have become holiday resorts and commuter towns. The Roman-origin cathedral city of Canterbury (chosen as the seat of the first English archbishop in 603) is an important feature in the landscape, as are medieval towns. Urban areas exert a strong influence on the character of large parts of the area. The western end incorporates parts of outer London, plus commuter towns such as Orpington, Bromley and Dartford, which developed from the late 19th century. Further west, the NCA boundary cuts through Rochester and incorporates the towns of Chatham, Gillingham, Sittingbourne and Faversham. On the Isle of Thanet, Margate, Broadstairs and Ramsgate developed as resorts over the 19th century. Former colliery sites and villages at the south-eastern end of the NCA contrast with the usual Kent landscape.

Historically large areas of the NCA were owned by the Church, which continued to manage large estates after the dissolution of the monasteries in the 16th century. By national standards, the area has large numbers of medieval houses and barns – especially across the fruit belt – which testify to a class of prosperous farmers that developed on these estates from the 15th century. Fewer arable-based farms developed to the east of the Stour, and elsewhere the diverse economy sustained the development of middling-scale farms (Draft Farmsteads and Landscapes Statement: North Kent Plain, English Heritage, 2012). Coastal military defences protecting the eastern approach to London have been established from the later medieval period right through to the mid 20th century, and survive as a sequence around the internationally significant Chatham naval dockyards and their related defences.

The intensification of agriculture has had an impact on the farmed landscape through arable expansion and the loss of traditional orchards. Changes in horticultural methods are also notable, for example the use of polytunnels. The impact of 20th century development is significant and includes pylons, landfill sites, mineral workings, transport networks (including the M2 and the Channel Tunnel rail link) and extensive urban expansion. The impact of development is exacerbated by the expansive and open nature of the lowlying landscape.