Crayford, Dartford & Erith Marshes Landscape Character Assessment

Crayford, Dartford & Erith Marshes Landscape Character Assessment Groundwork South East London March 2006

1. Purpose 1.1. This study is intended  to assess and record the existing landscape character of Erith Marsh, Crayford Marsh & Dartford Marsh, within the site boundaries defined in the Managing the Marshes project,  to clearly set out those distinct and recognisable elements that make the Marshes different from other landscapes, and are most important in creating a ‘sense of place’.  to identify using professional judgement the existing quality and intactness of the landscape and its elements, and identify character areas within the marshes where areas differ  to identify in terms of landscape character any opportunities for enhancement,  to identify pressures or issues that can impact the character of the place  to provide a basis for the development of coherent framework plans that can increase the value of the Marshes for access, biodiversity and prosperity and retain a sense of place.

2. Methodology 2.1 This landscape character assessment has been undertaken in accordance with guidance for studies of this scale and purpose set out in ‘Landscape Character Assessment, Guidance for England & Scotland’ Countryside Agency 2002 (www.countryside.gov.uk/images/LCA_Guidance_tem2-19316.pdf) by Groundwork South East London between June 2005 and March 2006 2.2 The work consisted of 2.2.1 Desk Study appropriate to the local nature of the character assessment, resources available for the assessment, the purpose of the assessment, and presence of existing assessments as a basis for additional detailed work, consisting  Review of Countryside Agency Character of England Map and the description of characteristics set out in Character Area 81: greater Thames Estuary www.countryside.gov.uk/LAR/Landscape/CC/SEL/greater_thames_estuary.asp  Review of relevant local and regional authority planning guidance for Bexley, Dartford, Kent & Greater London  Review of published and draft stage reports considered throughout the strategy development, having specific regard to landscape character assessments and character descriptions relating to Erith, Crayford, & Dartford Marshes 2.2.2 Site surveys, carried out in August and November 2005, recorded using a standard checklist, annotated maps & photographs.

3. General Landscape Character 3.1. The marshes lie in the Thames Estuary, and are largely low lying open floodplain areas on the urban fringe, in use primarily as grazing for horses. They are bounded to the north by the River Thames, and to the east, west & south by urban land uses, in the form of industrial areas, housing and infrastructure. The river Darent, a tributary of the Thames, runs south to north between Crayford & Dartford Marshes forming the administrative boundary between Bexley in London and Dartford in Kent. The Darent does not represent an edge in terms of landscape character.

3.1 Extensive views, Crayford Marsh

3.2 The marshes lie within Countryside Character Area 81 (CCA81) Greater Thames Estuary and have many typical characteristics:    

   

Extensive open spaces dominated by the sky, in a predominantly flat, low lying landscape Strong feeling of remoteness and wilderness persist Traditional use as unimproved wet grazed pasture Open grazing pasture patterned by a network of ancient and modern reed fringed drainage ditches & dykes, numerous creeks & few vertical boundaries such as hedges or fences Generally tree cover limited to farmsteads & dwellings on higher, drier pockets of ground Distinctive military heritage such as 20th century pillboxes Pressure on edges from urban, industrial and recreational developments together with associated infrastructure often on highly visible sites The marshes themselves subject to the “chaotic activity” of various developments including waste disposal, mineral extraction, power stations, and industry

3.2 WW2 Structures, Crayford Marsh

3.3 Extensive views, Erith Marsh

3.3 Notable divergences from the general character as described in CCA81 do exist: 



The influence of the Thames on the landscape at Erith Marsh is less apparent than at Crayford/ Dartford Marshes, as is the sense of extensive openness, remoteness and wilderness. This is due in part to the large industrial buildings/sites on adjacent land, and in part to topography and to the low vantage point of pedestrian access through Erith Marsh. Thames river defences obstruct views to the river in the northern section, and the embankment carrying the Eastern Way, which provides an elevated view for vehicles, creates a visual and physical barrier within the marsh between northern and southern sections. At the southern site boundary, extensive tree cover beyond the East Thamesmead Business Park and the rising wooded ridge of Lesnes Abbey Wood reinforce containment of the landscape north & south. However, despite visible buildings such as the towers beside Southmere Lake, or gas holders and warehousing to the east, expansive views from ground to sky east & west dominate, helping to retain the remaining Thames estuary scale of this marsh.

3.4 Enclosure near Eastern Way, Erith Marsh

Some areas have a greater degree of enclosure due to vegetation than is typical, and consequently a more intimate scale, notably Dartford Marsh at its eastern edge, with tall hedgerows, small field sizes and increased tree cover associated with the former hospital site, its historic tramway, and the former fireworks factory site.

3.5 Enclosure at Dartford Marsh

4.

Local & Regional Policy Documents: Existing Landscape Assessment

4.1.

The Thames Strategy East Character Assessment

4.1.1.

Erith Marsh is described as “remnant marshland”, with flat low lying topography. It “contrasts well” with the surrounding built up area. The East London Sewage incinerator is identified as landmark building of significance, on the Thames frontage.

4.1.2.

Erith Marsh is a site of Metropolitan Importance for Nature Conservation and “one of a few remaining examples of Thames side grazing marshes” It is a UK priority habitat supporting national and local BAP species.

4.1.3.

Crayford & Dartford Marshes are seen as part of a landscape of flat open marshland on both sides of the Thames. Crayford & Dartford Marshes comprise areas of grazing marsh drained by a network of ditches and divided by the “sinuous” River Darent. River defences are present as bunds to both sides of the Darent and along the river frontage . The Darent flood barrier is identified as a landmark of significance.

4.1.4.

Crayford & Dartford Marshes & the river Darent provide both Thames-side grazing marsh and salt marsh, supporting nationally scarce species, UK BAP priority habitats, and Sites of Metropolitan and Borough Importance for Nature Conservation.

They are described as part of a continuum with the inner Thames Marshes and Erith Marsh.

4.2 Kent County Council: Landscape Character Area Description ‘Western Thames Marshes’ (http://extranet7.kent.gov.uk/klis/resources/landscapeassessment/Landscape%20Assessment%20of%20Kent%20October%202004.pdf 4.2.1 Only Dartford Marsh lies within Kent and is described in the study, however in general, the landscape character description is applicable to Erith, Crayford & Dartford Marshes. The text below is largely taken from the document.

4.2.2 Generally the area is low-lying at or below five metres Above Ordnance Datum (AOD). Formed from alluvium deposits, there is a consequent lack of natural landform features. There has been a steady and significant loss and degradation of the once predominant landcover of grazing marsh, resulting from conversion to improved grassland, arable and urban/industrial use (e.g. mineral workings, industrial buildings).

Fragmentation and isolation of the marshland landscape, is emphasized, created by extensive urban and industrial development. Land use is described as a complex, often discordant, mix of estuarine industry, urban development, river uses (shipping channels and port facilities), remnant grazing marsh and arable farmland. The study identifies that only a few scattered tiny pockets of grazing marsh habitat remain, & saltmarsh is confined to a thin strip beyond the tidal defences.

4.2.3 The dominant land use on Dartford Marsh is described as improved grassland (converted grazing marsh) with some areas degraded by neglect. Dykes, ditches, remnants of traditional grazing marsh, wetlands and scrub are important localized features. The majority of Dartford Marsh is designated as a Site of Nature Conservation Interest (SNCI) The key habitats listed are estuarine mosaic, ditches/river, grassland and scrub.

4.2.4 The Cultural and historic landscape context is described: “The density of Palaeolithic archaeological finds in the area is perhaps the highest in Kent… . This area of the Thames has strong cultural associations with maritime painting.

In the 17th century the landscape of the southern shore of the Thames formed the setting for the work of important artists such as Isaac Sailmaker and William van de Velde, younger and elder; and later with painters such as Charles Dean, Alexander Maitland and William Wyllie and in more recent years with the work of the Wapping Group of painters. Literature is also linked to this maritime setting with such writers as Joseph Conrad.’

4.2.5 Characteristic Features: Landscape Analysis The study describes these areas of low-lying, open marshland as “greatly fragmented by views of industrial and housing development, creating discordant fragments of the character area. Views out are limited by sea defences and development. There are many large-scale visual detractors such as…. industrial parks, with associated access roads and signage, some instances of tipping.

Localised ditches, wetlands and scrub raise the ecological profile of the area, but only operate as weak networks, with the ditches being generally unmanaged and scrub vegetation becoming more prevalent. Some former grazing marsh has been converted to improved grassland. There is very little evidence of the cultural elements of the former estuarine grazing marsh or of natural links with adjacent areas - the functional integrity of this area is very poor.

The built form and general land use within the area has a high negative impact.

Many elements within the landscape such as roads and structures are recent and have become characteristic of the area, but are not locally distinct. Urban skyline features can be said to be recent characteristics. The original sea defences and drainage patterns, which are the remnants of the historic character of the area, are generally overwhelmed by large engineering bunds and have become degraded through lack of appropriate management of watercourses. This is potentially a very distinctive landscape which currently has a poor sense of place. The openness of the area means that visibility is high”.

4.2.6 In summary, the study states        

Pattern of elements: Incoherent.

Detracting features: Many.

Cultural integrity: Poor.

Ecological integrity: Moderate.

Distinctiveness: Characteristic.

Continuity: Recent.

Landform: Apparent Extent of tree cover: Open

4.2.7 Recommendations The study recommends a new framework be created for the remaining area of marshland and open pasture, incorporating adjacent areas of commercial or residential development. In degraded areas, landforms should incorporate new managed wetland and drainage features, and enhance the existing historic features of the landscape such as ditches and dykes. Enhancing the management of existing semi-natural grazing marsh and drainage systems is recommended to reinstate habitat alongside action to create new habitats such as reedbeds and salt marsh. Further, the report proposes to create “a visual containment to the remaining undeveloped marshland using features of land drainage and marsh e.g. a major peripheral drain which also serves as a natural habitat.”

5. Site Survey 5.1 Topography & Drainage The Marshes are predominantly low-lying at or below five metres above Ordnance Datum (AOD). The landscape has few natural landform features, being formed from alluvium. At Erith, the east -west orientation of the Thames Valley Floodplain is evident. South of the marsh the land rises as the deciduous woodland of Lesnes Abbey Wood, a part of the Greenwich Ridge, which at its highest point in Shooters Hill is some 120m AOD. At Crayford Marsh, south of Moat Lane, the land rises more gently, as open grazed land.

Tree cover is limited to the immediate vicinity of ‘The Grange’, a characteristic feature of the Thames Marshes identified in CCA81.

Man made topography is present in the form of large engineering ‘bunds’ approximately six metres above the general land level, carrying infrastructure and forming flood defences.

From within the marshland, the embankments limit extensive views. While containment detracts from the estuarine scale and typical landscape character, the impact of surrounding “discordant” urban land uses is reduced, and a landscape of more intimate rural character is created. However, where footpaths are located on the bunds, the views are expansive, and the scale, remoteness and sense of wilderness are restored.

The marshes are drained by a characteristic network of ditches, which vary in their condition. Some, either consistently managed or recently reprofiled provide valuable habitats. Expanses of open water are visible, particularly at Erith Marsh, for example the Great Breach Dyke. At Erith, surrounding developments at the Belvedere industrial area and infrastructure such as the Eastern Way have retained and protected the marsh drainage system. At Crayford & Dartford Marshes, interventions such as the Wallhouse Road, and recreational uses have fragmented the system, and interrupted flows. Some channels have become degraded, and dried out, with scrub vegetation becoming more prevalent.

5.1 Greenwich Ridge, Erith

5.2 The Grange, Crayford

5.3 Great Breach Dyke, Erith

5.2 Vegetation Primarily open grazing land, with few vertical boundaries such as hedges or fences, mainly grazed by horses and patterned by a network of ancient and modern reed fringed drainage ditches & dykes. Saltmarsh is confined to thin strips beyond the tidal defences around Erith Yacht Club, and along the River Darent into Crayford Creek. Trees are located mainly at boundaries with surrounding urban areas, or as previously mentioned limited to farmsteads & dwellings on higher, drier pockets of ground.

5.4 Grazing Marsh, Crayford

Areas of all three marshes show increasing growth of hedgerow species, both along boundaries, and as invading scrub where land is not grazed.

The area to the east of Dartford Marsh allied with the former hospital and historic tramway, and the area just north of Eastern Way at Erith Marsh are extensive areas of this type.(Fig 3.5) Increased enclosure creates a different landscape character.

5.5 Encroaching Scrub, Crayford

5.6 Saltmarsh, Erith Yacht Club

5.3 Land Use & Management 5.3.1 Land Use: Land use is well described by Kent County Council’s character assessment (Sect 4.2), as “a complex, often discordant, mix of estuarine industry, urban development, river uses (shipping channels and port facilities), remnant grazing marsh and arable farmland.�

5.7 Grazing, Erith Marsh

The marshes themselves are primarily in use as grazing for horses, with some provision for recreation. Generally, where not in use as grazing marsh, Thames side uses bounding and situated in the marshes are industrial. Housing is largely set back from the rivers edge, with the exception of the Thamesmead estate which lies between the train line and the river, immediately west of the Erith Marsh. Away from the riverside, there is a mix of industrial/ infrastructure uses and housing Saltmarsh is confined to a thin strip beyond the tidal defences around Erith Yacht Club, and along the River Darent into Crayford Creek. Grazing marsh habitats remain; at Erith Marsh alongside sympathetic recreational/ ecological use, at Crayford Marsh north of Moat Lane and west of the industrial estate, & at Dartford Marsh on land closest to the Thames and near the historic tramway. Other areas of Dartford Marsh north of the former hospital site are improved grassland, land in leisure use for clay pigeon shooting, arable farmland, or former industrial uses now being colonized by pioneer habitats. To the west of the former hospital site, the landscape is in leisure use for motorcycle scrambling/ paint balling, and to the south has been subject to small scale mineral extraction, and landfill. West of the former hospital, on Crayford Marsh, landfilling operations are nearing completion, and some areas of former landfill have been restored as rough grassland.

5.8 Industry, Crayford Creek

5.9 Motorcycle scrambling, Dartford Marsh

5.3.2 Management: The marshes are managed to differing degrees determined by landownership, management objectives and existing management plans & obligations.

Areas of Erith Marsh are increasingly managed for wildlife value and access. Other areas of the marshes demonstrate care in management as grazing marsh, with efforts being made to avoid overgrazing , to manage ditches and dykes remove scrub, maintain fencing etc.

In other areas, neglect is evident.

5.10 Overgrazing, Erith Marsh

Surrounding land uses also have a significant impact on landscape character. The riverside industrial uses are accessed by narrow roads that are not heavily used outside business hours, are poorly lit and not overlooked. There is considerable flytipping associated with these accessible routes.

The foreshore itself is strewn with detritus from the river, substantial quantities of domestic and commercial waste, which detracts from the wilderness character of the riverside, and adds to the impression of neglect.

5.11 Fly tipping Erith Marsh

5.12 Area managed for habitat, Erith Marsh

4.2.

5.4 Landscape elements, features and views.

5.4.1 Elements The characteristic elements of the marshes are low lying open grazed landscape with few boundaries and little tree cover. Boundaries within the marshes are characteristically defined by agricultural fencing, hedgerows and drainage ditches.(Fig 5.13 ,& Fig 5.1,5.3).

Colours are muted, against large skies. Materials are primarily ‘raw’ ie unpainted, detailing is utilitarian and minimal, paths and tracks are of blinded stone without kerbs. Elevated engineered flood defence bunds define the rivers edge, usually topped by access tracks.

(Fig 3.1, 7.2) Other bunds carry road infrastructure across the floodplain.(Fig 3.4, 5.17) Some variation exists, a granite setted former tramway and painted iron fence remain from the former Joyce Green Hospital and tramway on Dartford Marshes.

Surrounding land uses bordering the Marshes, and industrial uses situated within them create discordant elements, for example the boundaries of industrial areas tend towards high security galvanized fencing or a mixture of ad hoc ‘urban’ fencing types such as chainlink, in poor condition. Housing and leisure uses bounding the marsh and public access also have no distinct harmonizing character, with boundaries tending to be ad hoc, in a variety of materials, and in varying condition. (Fig 5.14)

Fig 5.13 characteristic boundary treatments within the marshes Fig 5.14 Boundaries with adjacent land uses

5.4.2 Features The openness of the landscape means any tall or large scale developments have the potential to be highly visible. In some instances these features add drama – for instance the Thames Water sludge powered generator at Erith Marsh, the Darent Barrier, and the QEII Bridge near Dartford Marsh, however others appear discordant, particularly larger industrial sheds with unsympathetic boundary treatments and urban amenity landscaping.

5.4.3 Views Characterised as extensive open spaces dominated by the sky, in a predominantly flat, low lying landscape, the marshes can be viewed extensively from any elevated vantage point.

The rising land to ‘The Grange’ (fig 5.2) provides views across both Dartford & Crayford Marshes and out to the Thames. River defence bunds at Crayford & Dartford Marshes provide changing extensive views across the marshes, the Darent, of surrounding housing and industry, of the Thames and of developments on the rivers northern bank. Bob Dunn Way provides views over Joyce Green Farm and of the Darent.

Erith Marsh can be seen from housing areas on Greenwich Ridge, from housing towers in the Thamesmead estate, and from the Eastern Way. Footpaths at Erith are not elevated, limiting views across the marshes ( section 3.3). The short section of Thames defences at Erith Marsh provides views across the northern section of the marsh, though environmental quality is compromised by adjacent areas of ‘brownfield’ former industrial land.

5.15 Industry allied with riverside

5.16 Town centres on higher ground (Erith)

5.5 Local Architecture & Settlement Patterns Traditionally, housing and town centres have been located on higher ground out of the floodplain, with industrial uses colonising remnant agricultural use towards the rivers edge and infrastructure connecting urban areas, often elevated above the floodplain on embankments. Demand for housing has seen more recent residential use on the floodplain.

5.6 Archaeology/Heritage See supplementary document

5.17 Highway Infrastructure, Erith Marsh

6. Landscape Character Areas (Refer to Plans) CA1: Grazing Marsh/ Former Grazing Marsh retaining open landscape character, or readily restored  CA1AGrazing Marsh areas retaining open landscape character, managed drainage and rotational grazing.  CA1B: Marsh areas retaining open landscape character, managed for access and wildlife value  CA1C: Grazing Marsh of reduced character due to overgrazing, high degree of enclosure, encroaching scrub, neglect of vegetation and/ or drainage systems.  CA1D: Former grazing marsh, retaining open character in arable or leisure use CA2: Salt Marsh CA3: Higher grazing land CA4: Amenity Grassland CA5: Industrial/Urban land uses  CA5A Industrial buildings in current use  CA5B: ‘Brownfield’ land recolonizing with pioneer species  CA5C: Landfill or extraction processes ongoing  CA5D: Former landfill/extraction

7

Key Issues /Recommendations 7.1 Pressures The landscape character of these marshes is predominantly in keeping with CCA81, however increasing enclosure, changing land use/ management practices, neglect, envirocrime and discordant elements detract from its distinctiveness and quality.

7.2 Elements for preservation/conservation Elements for preservation/conservation in terms of landscape character, include the integrity of the drainage system, the low lying openness and apparent extent of the marshes, their muted colours, and simple detailing of elements in the landscape. (see Design Guidelines). Drainage, grazing and encroaching vegetation can be more carefully managed, and sympathetic uses encouraged through the Managing the Marshes project and by the Boroughs as part of their planning processes.

7.3 Elements for mitigation/screening/enhancement Management as grazing marsh and for access and habitat value would enhance existing landscape character where the remaining scale allows. Where extent is limited by surrounding land uses, issues other than landscape character should determine appropriate treatments, though detailing and vegetation can foster continuity with the wider marsh landscape. The impact of discordant elements can be reduced, and landscape character enhanced by more consistency in detailing of boundary treatments and public access points, and by careful choices in detailing and materials.

The open landscape allows high visibility, and new developments will have high impact.

Woodland blocks or tree screening are not appropriate and should be avoided, earth bunds may provide screening where essential. Areas of neglect should be brought to the attention of land owners, and appropriate management encouraged.

Access via remote roads onto the marshes create opportunities for envirocrime, and would benefit from secure access control at entry points closer to the main highway

7.1 Great Breach Dyke Erith

7.2 Industry Crayford Marsh

7.3 Access Road, Erith Marsh