CROSSRAIL ASSESSMENT OF ARCHAEOLOGY IMPACTS, ……IMPACTS, TECHNICAL REPORT. PART 4 OF 6,...

CROSSRAIL ASSESSMENT OF ARCHAEOLOGY IMPACTS, TECHNICAL REPORT. PART 4 OF 6, SOUTH-EAST ROUTE SECTION 1E0318-E2E00-00001

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Cross London Rail Links Limited 1, Butler Place LONDON SW1H 0PT Tel: 020 7941 7600 Fax: 020 7941 7703 www.crossrail.co.uk

CROSSRAIL

ASSESSMENT OF ARCHAEOLOGY IMPACTS

TECHNICAL REPORT

PART 4 OF 6, SOUTH-EAST ROUTE SECTION: ISLE OF DOGS TO ABBEY WOOD

FEBRUARY 2005

Project Manager: George Dennis Project Officer: Nicholas J Elsden

Authors: Portia Askew, Julian Bowsher, Jon Chandler, Rupert Featherby, Isca Howell, Heather Knight, Pat Miller, and Mike Morley

Museum of London Archaeology Service © Museum of London

Mortimer Wheeler House, 46 Eagle Wharf Road, London N1 7ED tel 0207 410 2200 fax 0207 410 2201 email [email protected]

Archaeology Service

16/02/2005

0006_R_South-East.doc

List of Contents 1 Introduction 1

2 Route overview 2

2.1 Zone A: Blackwall Tunnel to North Woolwich 2

2.1.1 Boundaries and layout 2

2.1.2 Topography and Geology 2

2.1.3 Archaeological and historical background 2

2.1.4 Selected research themes 5

2.2 Zone B: The River Thames to Basildon Road, Plumstead 7


2.2.2 Topography and Geology 7



2.3 Zone C: Basildon Road, Plumstead to Battle Road, Belvedere 11


2.3.2 Geology and Topography 11



3 Scheme Description 14

3.1 Overview of Crossrail Works in South-East Route Section 14

3.1.1 Permanent Works 14

3.1.2 Construction 14

3.1.3 Design Options 14

3.2 The Route Windows 14

3.3 Route Window SE1: Blackwall Way and Limmo Peninsula Shafts 16

3.3.1 Overview of Route Window SE1 16



3.4 Route Window SE2: Custom House Station 16



3.5 Route Window SE3: Connaught Tunnel 18



3.6 Route Window SE4: North Woolwich Portal and Thames Tunnel 18



3.7 Route Window SE5: Arsenal Way Shaft 19



3.8 Route Window SE6: Plumstead Portal 19



3.9 Route Window SE6A: Manor Wharf 20

3.9.1 Overview of Route Window SE6A 20

3.10 Route Window SE7: Church Manorway Bridge 21



3.11 Route Window SE8: Abbey Wood Station 22



4 Site assessments 23

4.1 Route-wide impacts 23

4.1.1 Protective Measures 23


4.1.2 OHLE masts 23

4.2 Route Window SE1 24

4.2.1 Site 232 Blackwall Way Shaft 24

4.2.2 Site 217 Limmo Peninsular vent shaft 29


4.3.1 Site 219 Victoria Dock Portal 33

4.3.2 Site 220 Custom House Station 37


4.4.1 Site 412 Connaught Tunnel 41

4.4.2 Site 222 Silvertown 46


4.5.1 Site 225 North Woolwich Portal & Vent Shaft 50

4.5.2 Site 233 Warren Lane Vent Shaft 55


4.6.1 Site 411 Arsenal Way Shaft 59

4.6.2 Site 295 Plumstead Road (near): ground settlement between search areas 411 & 227 63


4.7.1 Site 227 Plumstead Portal 65

4.8 Route Window SE6A 69

4.8.1 Site 413 Manor Wharf 69

4.9 Route Window SE7 and SE8 76

4.9.1 Site 400 Abbey Wood Station and Plumstead to Abbey Wood 4-Tracking 76

5 Appendix 1: Site specific assumptions 81


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1 Introduction

This report is Part 4 (of 6) in a specialist technical study on archaeological resources, produced as part of the Environmental Impact Assessment for Crossrail. It covers the proposed Crossrail route between Blackwall in the west and Abbey Wood in the east, and contains an archaeological overview of that route section, plus detailed assessments for individual Crossrail sites along it. A full introduction is included in Part 1 of this technical report, which should be referred to for details of the background to the project, project description, structure of the technical report, and methodology. The potential impacts of virtually all of the proposed works on archaeological remains would be mitigated by preservation by record. There are no residual impacts assessed as significant.


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2 Route overview

For an explanation of the purpose and structure of the route overview, please see Part 1 of the archaeology technical report, section 1.6.5.

2.1 Zone A: Blackwall Tunnel to North Woolwich

Route windows SE1 to SE3 Sites 232 Blackwall Way, 217 Limmo Peninsula, 219 Victoria Dock Portal, 220 Custom House, 412 Connaught Tunnel, 222 Silvertown, 225 North Woolwich

2.1.1 Boundaries and layout Zone A begins on the west side of the river Lea at the Blackwall Tunnel, corresponding to the end of the Crossrail Central Section and runs south-east to another topographic boundary, the Thames. It includes the former marshland that in the 19th century became an industrial and commercial zone extending from the lower Lea valley (Bow Creek); through Canning Town and the Royal Docks, along the north bank of the Thames to Silvertown and the ferry crossing at North Woolwich. The whole of the zone lies within archaeological priority areas in the London Boroughs (LBs) of Tower Hamlets or Newham.

2.1.2 Topography and Geology Zone A is characterised by reclaimed marshes around the confluence of the Thames and a major tributary, the Lea. Here eroded terrace gravels, laid down in earlier floodplains of the river, are overlain by a sequence of more recent peats, silts, and clays. This low-lying alluvium is bounded to the north by higher ground on the terrace gravels at Poplar, Plaistow, and West and East Ham, although the alluvial floodplain associated with the Lea estuary extends further inland. During the prehistoric period, sea and river levels within the estuary fluctuated between shallow (regression) phases characterised by peat formation and transgressions when clays were deposited in deeper flood plain conditions. One of the regression phases (known as Tilbury IV) has been identified throughout the Upper Thames area. The peats date from c 1500–800 BC (the Bronze Age) and contain preserved organic material: both natural palaeo-environmental evidence such as trees, pollen and floral remains and occasionally man-made structures, eg timber trackways or log boats. All of Zone A is low-lying, with ground level between c 2 and 3m OD.

2.1.3 Archaeological and historical background

Hunter-gatherer landscape (c 500,000 BP – 4000 BC)

No in situ remains from the Palaeolithic are anticipated in this zone, as they will have been reworked by changes in the course and floodplain of the Thames. Animal remains


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such as an elephant tooth and a mammoth tusk found during work on the Blackwall tunnel were thus residual in later geological deposits. Following the end of the last glaciation, the Thames and the lower Lea followed a course of multiple braided channels, which accumulated organic sediments as they became disused, between c 11,000 and 9000 BC. This suggests an environment of marshes, shallow watercourses, sand banks and islands where hunting, fowling, fishing and plant resources would have attracted nomadic Mesolithic groups. Such landscapes may in part have been sealed and preserved by alluvium in subsequent transgression phases, but they would be characterised by transient activity rather than settlement. They are also likely to have been extensively truncated by down-cutting and erosion from later channel formation. Rising sea levels and progressive flooding of the Thames estuary would have led to the inundation and abandonment of traditional hunting grounds, placing greater pressure on resources inland, and there is some evidence for Late Mesolithic activity further up the tributary valleys in the London region, on valley slopes and around the headwaters of tributary streams. Despite this background potential, evidence for human intervention in the landscape is currently restricted to a few flint tools, probably from mobile groups traversing the zone in the course of daily or seasonal routines. Overall archaeological potential: moderate for Mesolithic chance finds, and high for contemporary palaeo-environmental sequences.

Accessing the marshes (c 4000 BC – AD 50)

Low, but gradually rising water conditions in the Neolithic and Bronze Age lead to the inundation of peripheral land, forming extensive marshes along the Thames and lower Lea valley. Evidence of a preserved flooded forest, found in the 19th-century construction of the East and West India Docks (and within a layer of peat on Charringtons Wharf, during excavations in 1992) is of this period. Permanent settlement was confined to the agricultural landscape of the higher gravel terraces a few hundred metres north of the Crossrail route, or on sandy islands (eyots) exploiting the marsh resources of the floodplain, as has been demonstrated from archaeological investigations around Silvertown and North Woolwich. Deeper channels and settlement areas were accessed across the marshes by the construction of timber trackways, mostly in the Bronze Age. The river channels would have been used not only for the hunting and harvesting of natural resources, but also as a place for ritual activity. The lower Thames valley is well known for the quantity of prehistoric metal objects dredged from the river and it appears that many of these were placed there during personal and social ritual observances, which took place at the water's edge. It is possible that some of the trackways were used for this purpose. Subsequently, rising river levels caused progressive flooding further inland, leading to the formation of the extensive Hackney, Poplar and Stepney marshes. These remained into the early medieval period, with settlement confined to the village of Poplar, around the High Street (which possibly follows a Roman route along the edge of the higher terrace


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gravels) and to a hamlet on the western edge of the zone, on the riverside at Blackwall. There is thus a background potential for river use and flood defence features such as revetments, causeways, trackways, fish weirs, and boats in the prehistoric, Roman, Saxon and medieval periods. Overall archaeological potential: moderate, increasing to high for associated palaeo-environmental sequences.

Roman settlements and infrastructure (c AD 50 – 450)

During the Roman period much of this zone would still have been marshy open land, although occupation evidence suggests that sea levels were much lower than they are today and that the marshes were drier, and were probably drained and extensively used. At the west of the zone, the alignment of Green Street and Boundary Lane may represent an ancient track coming down onto the marsh. Pottery found near this route might have been associated with a farmstead. To the east is another possible Roman road, marked by East Ham High Street and East Ham Manor Way, leading from the higher ground to the north down to the ferry crossing at North Woolwich, which is of at least medieval origin. Evidence of Roman occupation has also been found in this area. Towards the end of the Roman period sea levels began to rise again leading to flooding in the area of Zone A. Overall archaeological potential: low, increasing to moderate in the vicinity of possible Roman roads and occupation sites.

Flooding and land reclamation (AD 450 – 1700) By the Saxon period (AD 450 – 1066) much of the floodplain of East London was once again marshland due to the rising levels of the Thames. To the north, on the higher and drier ground, were the manors of West Ham and East Ham. There is documentary evidence for a small settlement at North Woolwich by 1086, probably centred around Hammarsh Marsh, owned by Westminster Abbey, although from the 13th-century flooding frequently occurred. Severe floods damaged pasture on land reclaimed by Stratford and Barking Abbeys, which held most of the remaining marshland and caused it to be abandoned. The settlement at North Woolwich was part of the parish of Woolwich, the majority of which lay on the south bank of the Thames, forming an outpost of Kent on the northern (Essex) bank, an administrative anomaly which may reflect the strategic importance of the ferry crossing here, referred to as being under royal control in 1320. After the dissolution of the monasteries in the mid 16th century, the responsibility for the upkeep of the sea defences and land drainage in this part of London came under the jurisdiction of a court of sewers. The marsh, which extended from Bow to Barking and south to the Thames, was at this time recorded as covering a total of 1747 acres.


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By the early 17th century much of the marsh had been drained and reclaimed although this was temporarily halted by severe flooding in 1612 and 1613. The ditches that were dug to drain the levels developed into major drainage dykes, becoming open sewers feeding into the tributaries of the Thames, and the river itself. This process of land reclamation continued into the 19th century. In Zone A flood prevention was vital to the establishment of good farmland, and as drainage and flood prevention improved so did the profitability of the land, which, by the end of the 17th century, was being used for market gardens supplying an ever expanding London market with fresh produce. Cargoes were transported by water from small ports and wharves along the Thames and the Lea. Overall archaeological potential: low, increasing to moderate in the vicinity of known settlements.

A centre of trade and industry (c 1600 – present)

Maps of the 18th century indicate that much of Zone A was still open grazing, probably below high tide level but protected by dykes and riverside embankments. However, by the middle of the 19th century its character had changed significantly, as London became an increasingly important international port and the associated area of docks, warehouses and industry expanded eastwards. The North Woolwich Railway opened in 1847 and accelerated the process, large factory complexes being built alongside it. It terminated at North Woolwich station, built in 1854. The Royal Docks were the last to be built in London and formed the largest area of impounded dock water in the world. The Royal Victoria was opened in 1855, the Royal Albert in 1880 and the King George V Dock in 1921. They finally closed to commercial shipping in 1981. Overall archaeological potential: high.

2.1.4 Selected research themes

Museum of London, 2002, A Research Framework for London Archaeology (page numbers in brackets).

• Understanding the significance of geomorphology, ecology, ecosystems and climate, hydrology, and vegetation and faunal development, on human lives. (79).

• Understanding London’s hydrology, river systems and tributaries particularly the role of the Thames (as boundary, communication route, resource, ritual focus etc) in shaping London’s history, and the relationships between rivers and floodplains. (79).

• Understanding the relationship between landscape, river and settlement, and the influences of the Thames in particular on communications and social interaction. (79).

• Understanding the origins of the prehistoric metalwork sequence from the Thames, and examining the links between the metalwork hoards deposited at the headwaters of river tributaries and other activities. (79).


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• Understanding the relationship between the Bronze Age wooden trackways and the settlements to which they presumably led, and what the trackways represent in terms of woodcraft and woodland management. (81).

• Understanding the reasons for evolution of the road systems, street layouts, river crossings and ferries, and their importance as engines of development and change. (Museum of London, 2002, 82).

• Understanding the development of London’s Docklands and Waterways. (82).


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2.2 Zone B: The River Thames to Basildon Road, Plumstead

Route windows SE4 & SE5 Sites 233 Warren Lane, 411 Arsenal Way, 295 Plumstead Road, and 227 Plumstead

Portal

2.2.1 Boundaries and layout This zone extends from the Woolwich Reach of the Thames eastwards to Basildon Road, Plumstead, a distance of 2.5km. Its eastern boundary is artificial, the end of Route Window SE5, although this corresponds to differing patterns of post-medieval land use between Zones B and C. Similar topography and alluvial geology, however, continues into Zone C. It includes medieval and later Woolwich, the military site at Woolwich Arsenal and Plumstead village. The south bank of the Thames and Woolwich historic centre are archaeological priority areas.

2.2.2 Topography and Geology The Crossrail route in Zone B is overlooked to the south by a ridge of higher ground, composed of sandstone and mudstone of the Lambeth Group, rising to over 50m OD to the south-east on Plumstead Common. The route itself follows the base of this ridge, where Head deposits (eg soliflucted chalk) have accumulated down-slope over Thanet sandstone. To the north, it overlooks the low-lying land of the Thames floodplain, which it enters east of Plumstead High Street, approaching the proposed Plumstead tunnel portal. The floodplain consists of alluvial silts and peats, representing a wider river bordered by marshes, channels and creeks, prior to reclamation and embanking. These overlie a faster- flowing late glacial river regime characterised by terrace gravels. The Plumstead and Erith marshes form a wide northward projection: the western end of the extensive North Kent marshes that are characteristic of the lower Thames and Medway estuaries.


Hunter gatherer landscapes (c 500,000 BP – 4000 BC)

A small number of Palaeolithic flint tools, from higher ground overlooking the Thames floodplain, suggest a background potential for the survival of Palaeolithic evidence within or beneath Head deposits at the base of the slope, in the general vicinity of the Crossrail scheme. The floodplain itself is of more recent date. Following the end of the last glaciation, the Thames had multiple braided channels, which accumulated marshy, organic sediments as they became disused, between c 11,000 and 9000 BC. This has been demonstrated by Mesolithic peat deposits from Battery Road, Woolwich, as well as a small number of flint tools from the Woolwich area. They suggest an environment with hunting, fowling,


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fishing and plant resources that would have attracted nomadic Mesolithic groups, but which may have been sealed and preserved by deeper deposits of alluvium during later transgression phases in the Thames estuary. Overall archaeological potential: low for Palaeolithic evidence (in areas of Head deposits); moderate for Mesolithic and high for supporting palaeo-environmental sequences (in areas of alluvium).

Marshland and littoral (c 4000 BC – AD 50)

The eastern part of this zone would have been affected by the formation of extensive marshes along the Thames valley (see Zone A) accessed by the construction of timber trackways, mostly in the Bronze Age. Permanent settlements would have occupied the rising ground to the south or islands within the marsh. A concentration of what are believed to be Bronze Age round barrows lies c 1 to 1.8km south of the Crossrail route, on Shooter’s Hill and Plumstead Common, in a prominent position overlooking the Thames, but little evidence of the contemporary agricultural landscape has so far been recovered. Where the promontory of higher ground reaches the Thames, at the Woolwich Power Station site, an Iron Age settlement was found and has been interpreted as a hill fort or oppidum (fortified proto-town), which may have served as a centre for administration and trade over a wide area. There is little other evidence to date for Iron Age activity in the surrounding area. Overall archaeological potential: moderate for the floodplain and the rising ground near the Woolwich Power Station site, increasing to high for associated palaeo-environmental sequences.

Roman settlements and infrastructure (AD 50 – 450)

The Roman landscape was dominated by two roads. On the ridge to the south, the route of the major arterial road from Dover to London, Watling Street, is marked by modern Shooter’s Hill. Within Zone B, a second, subsidiary route followed the lower slopes towards Woolwich, along what is now Plumstead High Street. The projected road alignments north and south of the river raise the possibility of a Roman ferry crossing at Woolwich (see Zone A, above). There was certainly a significant settlement here, the extent of the cemetery beside the road in the vicinity of Plumstead Road and the Royal Arsenal suggesting relatively dense Roman occupation. A series of settlements along the roads is likely, with villas and farmhouses occupying the fertile Cray and Darenth valleys c 9km to the east of Woolwich. It also seems that the marshes on both sides of the Thames were being reclaimed, with farming settlements occupying slightly higher areas within the floodplain (see Zone A, above). Pottery, burials and the foundations of buildings were reported in the late 19th century from the Erith and Plumstead marshes. Overall archaeological potential: moderate, particularly in Woolwich and along the Roman road.


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A reclaimed landscape (AD 450 – 1700)

Although rising sea levels at the end of the Roman period would have threatened habitation within the marshland, more permanent settlement remained focused inland, around the road and strategic ferry crossing, as evidenced by the medieval villages of Woolwich and Plumstead. The respective parish churches occupy rising ground on the edge of the marsh and may both be pre-Conquest foundations, suggesting Saxon settlements. Progressive land reclamation, mainly for pasture, was a feature of Zone B during the medieval and post-medieval periods, while the unenclosed marsh was still used for fowling and fishing. On frequent occasions high tides caused the river to break through the defences and flood the farmland behind. Once outside the historic nucleus of Woolwich, the Crossrail route passes through what was until the 19th century open land between Plumstead village and the marshes to the north. Features relating to this rural landscape such as embankments, drainage ditches, and field systems are therefore to be expected. Overall archaeological potential: moderate.

A centre for industry (AD 1700 – 2000)

Because of the proximity to the river, the agricultural landscape had industrial elements, particularly the exploitation of natural resources such as gravel quarrying and brick making. The industrialisation of the riverfront began with ship-building and the establishment of the Tudor royal dockyard at Woolwich. The significance of economic pressures, particularly from the north as industrial Woolwich expanded, can be seen in the resistance to development and enclosure of the commons in the area as late as the 1870s, when troops were used to quell riots over this issue. The promontory at Woolwich retained the strategic importance it had in earlier times. Construction of the royal dockyard and later fortifications against the Dutch led to the establishment of a military ordnance depot. The main government foundry moved from Moorfields to the Woolwich site, originally known as the Warren, in 1715–17 and was renamed the Royal Arsenal in 1805 by George III. Buildings from this period survive on the site. At its peak in World War I, the Royal Arsenal employed about 80,000 workers and ceased manufacturing armaments in 1967. Both industrialisation of the marshes fronting the river and suburban development inland were given greater emphasis by the arrival of the railway in the 19th century. Overall archaeological potential: high at Woolwich Arsenal.




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• Identifying the industries that especially represented London (Museum of London, 2002, 74).

• Understanding the relationship between landscape, river and settlement, and the influences of the Thames in particular on communications and social interaction. (Museum of London, 2002, 79).

• Understanding the relationship between the Bronze Age wooden trackways and the settlements to which they presumably led, and what the trackways represent in terms of woodcraft and woodland management. (Museum of London, 2002, 81).

• Understanding the differences, if any, between burial practices in the city and outlying cemeteries. (Museum of London, 2002, 85).

• Understanding the nature and meaning of the deposition of metalwork in the Thames and at the headwaters of river tributaries. (Museum of London, 2002, 86).


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2.3 Zone C: Basildon Road, Plumstead to Battle Road, Belvedere

Route Windows SE6 to SE8 Sites 400 Abbey Wood, and 413 Manor Wharf

2.3.1 Boundaries and layout The Crossrail route follows the edge of the floodplain, with the former Plumstead and Erith marshes to the north and rising ground to the south. Its eastern boundary lies close to the Thames itself, at a point where (as at Woolwich) the higher land forms a promontory into the river.

2.3.2 Geology and Topography The Crossrail route in this zone follows the margins of the floodplain where the deposits consist of post-glacial alluvial sequences, crossed by tributary streams running north towards the Thames. The underlying solid geology (generally Upper Chalk) is exposed at the base of the Thames valley escarpment, c 10 to 150m to the south.


Hunter gatherer landscapes (c 500,000 BP – 4000 BC)

There is a background potential for Palaeolithic evidence within or beneath Head deposits where these are present along the base of the valley slopes and palaeochannels representing former streams flowing northwards on the terrace slopes between Lesnes Abbey Woods and Belvedere. The location on the margins of the floodplain, at the junction of drier areas suitable for habitation and the exploitable natural resources of the marshes and channels, would also have been attractive for post-glacial hunter gatherers, eg in the Mesolithic. Flintwork of this date has been recovered in the eastern part of the zone. Here, such horizons may be sealed by more substantial alluvial deposits laid down in deeper water conditions during later transgression phases within the estuary. Overall archaeological potential: low for Palaeolithic evidence (in areas of Head deposits); moderate for Mesolithic and high for supporting palaeo-environmental sequences (in areas of alluvium).

Marshland and littoral (c 4000 BC – AD 50)

Development of the zone continued to be dominated by the river regime throughout the prehistoric period when low, but gradually rising water conditions in the Neolithic and Bronze Age lead to the formation of very extensive marshes along both sides of the Thames valley (see Zone A). As in later periods, more permanent occupation and the emerging agricultural landscapes were focused on higher ground south of the route, not subject to flooding, or islands in the marsh. However, settlement evidence is sparse in the zone, confined largely to evidence


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of ‘ritual activity’ in the form of a suggested Bronze Age barrow in Abbey Wood and two ‘beakers’ from a gravel pit near Erith, both on the higher ground. Evidence of the associated uses of the marsh is more likely, including organically preserved palaeo-environmental evidence and flintwork within the alluvial sequences (possibly associated with land surfaces). These uses do not appear to have involved land reclamation but required access, facilitated by the construction of timber trackways, mostly in the Bronze Age, an example of which was excavated at the eastern end of the zone. Overall archaeological potential: moderate, increasing to high for associated palaeo-environmental sequences.

More organised use of the marshes (AD 50 to c 1100)

Whilst comparison with Zones A and B suggests that slightly higher parts of the flood plain may have formed suitable sites for occupation during much of the Roman period, there is so far no evidence from this zone. Although much of the area remained subject to flooding, it is possible that there was more organised land management and that some of floodplain was perhaps used for farming and settlement in the Roman period. There may also have been a Roman track skirting the edge of the floodplain, taking much the same route as the present railway. Such marginal use of the marshlands would have continued into the Saxon and medieval periods without much change. Overall archaeological potential: low, increasing to moderate in the vicinity of any higher areas within the flood plain.

Land reclamation (1100–1840)

Systematic reclamation of the marshland began with the foundation of Lesnes Abbey in 1178. It occupied the higher, drier ground south-east of the present Abbey Wood station. The allocation of much of the Erith Marshes to the Abbey led to extensive land improvement within its estates, to increase pasturage and thus rental income, although it was not a wealthy foundation and maintaining the river walls and drainage strained resources. Medieval reclamation and agricultural features including revetments, embankments, drainage ditches and field systems are therefore to be expected. As in the Roman period the possibility of more permanent occupation on the marsh, such as farmsteads and associated structures, is less clear. Known medieval settlements such as Picardy Street are once again focused to the higher ground south of the present railway. This essentially open rural landscape, with undeveloped marginal land, persisted well into the 19th century. Overall archaeological potential: low, increasing to moderate in the vicinity of known settlements, including the main Abbey precincts.


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Suburban advance (1840–present)

Although the railway arrived in the 1840s, the stimulus to development was slow to materialise. Crossness sewage works was situated to the north of the Crossrail route in the 1860s precisely because the area was remote from settlement. Even the 1888 Ordnance Survey shows extensive open land, industrial use being largely confined to mineral extraction. Suburban development began at this time, for example at Abbey Wood and Belvedere, but only gained momentum in the 20th century, particularly with the construction of Thamesmead and associated road infrastructure across the former northern marsh area. Overall archaeological potential: moderate.



• Understanding the relationship between landscape, river and settlement, and the influences of the Thames on communications and social interaction (Museum of London, 2002, 79).

• Understanding the origins of the prehistoric metalwork sequence from the Thames, and examining the links between the metalwork hoards deposited at the headwaters of river tributaries and other activities. (Museum of London, 2002, 79).

• To develop a holistic approach to the study of sea walls and flood defences in the estuary landscape as evidence of climatic change, and reclamation, management and exploitation of the marshland resource. (Williams & Brown, 1999, 32)


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3 Scheme Description

3.1 Overview of Crossrail Works in South-East Route Section

3.1.1 Permanent Works For part of the southeast route section, Crossrail will use existing main line railway alignment. Crossrail will operate in tunnel to the west of Victoria Dock portal and will serve a reconstructed surface station at Custom House. The route will then follow the existing alignment currently used by the NLL through a refurbished Connaught Tunnel to Silvertown. Crossrail will then descend a ramp to the North Woolwich portal where a new twin-bore tunnel will be constructed that will surface at Plumstead portal, located between the existing Plumstead and Abbey Wood stations. Abbey Wood station will be reconstructed to allow twelve Crossrail trains per hour to terminate. It is assumed that the NLL, south of Stratford, is closed by the DLR extension to Stratford International line from Canning Town, which will include closure of Silvertown and North Woolwich stations and the withdrawal of services through the Connaught Tunnel.

3.1.2 Construction Construction methods for the Western route section are described in further detail in Chapter 11 of the Environmental Statement, under each route window.

3.1.3 Design Options Design options which have been considered, but not taken forward, are described in Chapter 11 of the Environmental Statement, under each route window.

3.2 The Route Windows

The scale of the works along the route varies. The table below summarises the main works (excluding enabling works) that will take place in the southeast section. Those route windows containing the more substantial works are highlighted with shading. The level of detail that is reported in subsequent sections for route windows SE1 to SE8 is commensurate with the extent of works that is proposed in each of these route windows.


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Main Elements of the Scheme within the Southeast Route Section (1) (Route windows with major works are highlighted)

Route Window Major Project Works Local Authority

SE 1 Blackwall Way & Limmo Peninsula shafts

Blackwall Way to Tarling Road.

• Blackwall Way shaft

• Limmo Peninsula shaft

LB Tower Hamlets

LB Newham

SE 2 Custom House Station

Tarling Road to Prince Regent Footbridge.

• Victoria Dock portal

• Reconstruction of Custom House station; modifications to DLR platform

• Realignment of DLR tracks

• OHLE

• New station entrance and footbridge

LB Newham

SE 3 Connaught Tunnel

Prince Regent Footbridge to Lord Street.

• Refurbishment of Connaught Tunnel

• Demolition of Silvertown station

• OHLE

LB Newham

SE 4 North Woolwich Portal & Thames Tunnel

Lord Street to 80 Beresford Street.

• North Woolwich portal

• New twin-bore tunnel (Thames Tunnel)

• Warren Lane shaft

• OHLE

LB Newham

LB Greenwich

SE 5 Arsenal Way Shaft

80 Beresford Street to Ann Street bridge.

• New twin-bore tunnel (Thames Tunnel)

• Arsenal Way shaft

LB Greenwich

SE 6 Plumstead Portal

Ann Street bridge to Marmadon Road

• Plumstead portal

• Replacement of White Hart Road bridge

• Two new tracks and track realignment

• OHLE

LB Greenwich

SE 6A Manor Wharf

• Refurbishment of Manor Wharf

• Dredging

LB Bexley

SE 7 Church Manorway Bridge

Marmadon Road to De Lucy Street.


• Replacement of footbridges on Church Manorway and Bostall Manorway

• Works to Eynsham Drive bridge

• OHLE

LB Greenwich

(1) Read in conjunction with maps in Volume 4 of the ES.


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Route Window Major Project Works Local Authority

SE 8 Abbey Wood Station

De Lucy Street to Tunstock Way

• New Abbey Wood sidings


• Two new platforms and new elevated station

• OHLE

LB Greenwich

LB Bexley

Route Window SE1: Blackwall Way and Limmo Peninsula Shafts

3.3.1 Overview of Route Window SE1 Within this route window the main Crossrail works will involve construction of the Blackwall Way shaft, the construction of the Limmo Peninsula shaft and the construction of twin-bore tunnels. The route window lies within LB Newham and LB Tower Hamlets. The proposed Blackwall Way shaft site is located along Blackwall Way, adjacent to commercial and residential development.

3.3.2 Permanent Works To comply with safety requirements, Crossrail will construct two shafts between the Isle of Dogs station and Victoria Dock portal. The Blackwall Way shaft will be used as an EIP. It will consist of a 9m diameter shaft located immediately to the south of Blackwall Way and adjacent to the Reuters Building car park and Virginia Quay Development. On the surface, a single storey building will be integrated with a boundary wall on Blackwall Way. A small area of hard standing will also be provided for emergency services and maintenance vehicles. The Limmo Peninsula shaft will be used as an EIP, ventilation and evacuation facility, and a principle tunnelling site. It will consist of a 25m diameter shaft located at the southern end of the Limmo Peninsula. The surface buildings will be included within a landscaped mound and an area of hard standing for maintenance vehicles and emergency services will be provided. The tunnelled section will comprise twin-bored segmental lined tunnels. Both the eastbound and westbound rails will lie at a depth of approximately 40m below ground level at the Blackwall Way shaft and 30m at the Limmo Peninsula shaft.

3.4 Route Window SE2: Custom House Station

3.4.1 Overview of Route Window SE2 Proposed works within the route window comprise the construction of the Victoria Dock portal, a new station at Custom House station, the installation of overhead line electrification equipment, and the construction of twin-bore tunnels. The route window lies within LB Newham.


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3.4.2 Permanent Works The Victoria Dock portal will be located approximately 150m east of Royal Victoria DLR station, and its location is determined by the gradients of the Crossrail tunnels, which must meet safety requirements. It will be constructed on the current alignment of Networks Rail’s North London Line (NLL), which is assumed to have ceased operation between North Woolwich portal and Stratford with the opening of the proposed DLR route to Stratford. The eye of the tunnels will be located opposite 250 and 250A Victoria Dock Road from where a ramp will be contained within a cut and cover box to the portal opposite 251A Victoria Dock Road. From this point, Crossrail will run in a retained cut to join existing track levels immediately to the west of Custom House station. A 22m by 22m by 27m deep chamber will be constructed to allow removal of the TBMs at the tunnel eye. After removal of the TBMs the chamber will be fitted out with an emergency escape and EIP facilities from the twin-bore tunnels. At surface level the facilities will be housed in an approximate 43m by 11.5m size surface structure. On the north side of the structure a hardstanding area will be provided for emergency assembly, emergency and maintenance vehicles on existing railway land. A new station at Custom House will be provided to serve the Royal Docks area. In order to accommodate this, the existing station at Custom House will be demolished although the DLR platform will be retained. Crossrail trains will use a new island platform on the north side of the station that will be 10m wide at the west end and 5m wide at the east end. Canopies will be constructed for the Crossrail and DLR platforms. Access will be provided at the west end of the station from a high level ExCel Centre walkway. The walkway will extend linearly from the ExCel Centre across Victoria Dock Road to the site of the former Barge Public House on the north side of the station. Access to the walkway from here will be provided by a stair, two escalators and a lift. The station which spans the DLR and Crossrail platforms, will be a two storey structure measuring 14m width, 32m length, and 17.5m above street level. The entrance on Victoria Dock road will be contained within a 9.5m x 11m x 29m enclosure. The bridge will be approximately 5.5m above street level and will be up to 10m wide. A deck will be constructed over the tracks that will support a concourse area and station building. The station design consists of a two-storey development built off the concourse deck. Conceptually the ticket hall consists of a portal or inverted ‘U’ shaped building. The ‘ground’ floor contains ticketing and ancillary facilities while the gate-line controls the flow of passengers through the portal. Station operations and staff accommodation are located on the first floor, which is accessible by both stairs and lift. Lifts and escalators serve between concourse and platform level providing step free access throughout. OHLE will be installed throughout the route window. This will also include a feeder station on the site of an existing substation located to the northwest of Prince Regent DLR station, to supply the High Voltage power to the Railway.


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3.5 Route Window SE3: Connaught Tunnel

3.5.1 Overview of Route Window SE3 The proposed works within the route window comprise the alteration and refurbishment of the Connaught Tunnel to OHLE, the demolition of Silvertown station, and the installation of OHLE. The route window lies within LB Newham.

3.5.2 Permanent Works Permanent works will consist of the alteration and refurbishment of the Connaught Tunnel to accommodate OHLE. The tunnel will become ellipse shaped and the floor lowered. Crossrail will use the alignment that is currently occupied by the single Network Rail track. The alignment of the tracks through the existing station will be unsuitable for use by Crossrail trains. The station will therefore be demolished although passive provision will be made for a future Crossrail station in the event of the development of adjacent properties.

3.6 Route Window SE4: North Woolwich Portal and Thames Tunnel

3.6.1 Overview of Route Window SE4 The proposed works within this route window comprise the construction of the North Woolwich portal, the twin bore Thames Tunnel, Warren Lane shaft, and the installation of OHLE equipment. The route window lies within LB Newham and LB Greenwich.

3.6.2 Permanent Works Crossrail will use the existing rail corridor located between Albert Road and Factory Road, and currently occupied by the North London Line. The railway corridor is constricted here, being flanked by Factory Road and Albert Road for much of its length. To the east of the junction of Tate Road and Albert Road Crossrail will descend into an open cut ramp to the portal. The tunnel portal itself will be located between the junctions of Winifred Road and Fernhill Street with Albert Road, from where the line will run in a cut and cover box to the tunnel eye. At the tunnel eye, located near to the junction of Henley Road and Factory Road, a chamber will be constructed to receive the TBMs that will be used to construct the main Thames Tunnel from Plumstead. This will be incorporated into the tunnel eye as a widening of the cut and cover works requiring some works outside the existing railway boundary. At the tunnel eye a shaft containing emergency escape stairs and EIP will lead to a surface structure housing plant rooms. At the portal a secondary emergency escape stair will be housed in a small surface structure. A landscaped area between surface structures will connect the area to the north and south of the railway corridor. Crossrail will construct a new twin-bore tunnel beneath the Thames between North Woolwich and Plumstead portals. Beneath the Thames, the tunnel will follow an


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alignment to the east of the Woolwich Ferry. At Warren Lane shaft on the south bank of the Thames, the eastbound and westbound tracks will lie at a depth of approximately 36m. To satisfy safety requirements for an intervention shaft at a maximum of every 1000m, Crossrail will need to construct two shafts for the 2600m long Thames Tunnel between Plumstead and North Woolwich portals. The shaft will be located on the corner of Warren Lane and Beresford Street and will contain EIP and ventilation facilities. The shaft will be 13.5m in diameter and a building (10m tall by 18m in diameter) will be constructed on the surface to house emergency intervention and ventilation equipment. OHLE equipment will be installed throughout the tunnel alignment.

3.7 Route Window SE5: Arsenal Way Shaft

3.7.1 Overview of Route Window SE5 The proposed works within this route window comprise the construction of the twin bored Thames Tunnel and Arsenal Way shaft. The route window lies within LB Greenwich.

3.7.2 Permanent Works Having passed beneath the Thames (see Route Window SE4), the tunnel will follow an alignment along the southern edge of the Royal Arsenal West site towards Network Rail’s NKL beneath Plumstead station (see Route Window SE6). Both the eastbound and westbound rails will lie at a depth of approximately 35m below ground level at Arsenal Way Shaft. A shaft is required in this area because the distance from the portal at Plumstead is approximately 1000m. The shaft will be located at the south eastern end of Woolwich Barracks Car Park with Plumstead Road to the south. It will have a diameter of 16m and contain ventilation, EIP and emergency evacuation facilities. Two surface structures will also be constructed (8m in height).

3.8 Route Window SE6: Plumstead Portal

3.8.1 Overview of Route Window SE6 The proposed works within the route window comprise the construction of the twin bore Thames Tunnel, Plumstead portal, White Hart Road Bridge, track realignment of the existing railway corridor, and the installation of OHLE equipment. The route window lies within LB Greenwich.


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3.8.2 Permanent Works The Thames Tunnel will follow the existing alignment of the North Kent Line (NKL) from a point immediately to the west of Plumstead station to the surface just west of Church Manorway Footbridge (see Route Window SE7). This will be located on the site of Plumstead Goods Yard, located to the east of Plumstead High Street. The tunnel eye of the Thames Tunnel will be located towards the south west corner of the goods yard. From the tunnel eye to the portal an approximate 100m long cut and cover box with associated surface structures will be constructed. The portal will be located approximately 150m to the west of White Hart Road. A ramp contained within an open cut will then bring Crossrail to existing track level opposite 139 Marmadon Road, to the west of Church Manorway. At the tunnel-eye, a 21m by 30m chamber will be constructed which will house the emergency escape and EIP facilities from the twin-bore tunnels. At surface level the facilities will be housed in an approximate 20m by 25m size surface structure. On the north side of the structure a hardstanding area will be provided for emergency assembly, emergency and maintenance vehicles on existing railway land. At the portal a secondary set of escape stairs will be provided with an associated surface structure. A new bridge will be constructed to the north of the existing structure to carry White Hart Road over Crossrail. The NKL will continue to use the existing bridge. To accommodate Crossrail, changes will be made to the layout of the NKL. To replace stabling sidings that will be removed to accommodate the tunnel, a new 250m long siding will be installed on the south side of the line to the east of Plumstead High Street. The siding will also feature a 20m long headshunt at the western end. Crossrail will occupy a position between NKL tracks so that cross platform interchanges between Crossrail and NKL trains can be provided at Abbey Wood. From a point east of White Hart Road, the northernmost NKL track will move northwards and will use a new bridge over the Crossrail tracks to reach the northern side of the railway alignment. The realigned track will move by up to 20m until it runs adjacent to the Crossrail tracks to the east of Church Manorway. To accommodate these works, Crossrail will acquire an approximately 15m wide strip of land along the northern boundary of the railway between North Road and Church Manorway. A 2m high noise barrier will be erected from the end of the portal ramp on both sides of the railway and run eastwards to Abbey Wood station. OHLE equipment will be installed throughout the route window.

3.9 Route Window SE6A: Manor Wharf

3.9.1 Overview of Route Window SE6A

The route window lies within LB Bexley, in a primarily industrial area. The proposed works within the route window comprise the refurbishment of Manor Wharf at the site of the former Belvedere power station. This will be required in order create a barge loading facility, at which excavated material, removed from Plumstead portal and the intervention shafts at Arsenal Way and Warren Lane, will be loaded onto barges for transport down river to landfill in Rainham, Essex.


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This site will be operational for 2.5 years from the start of construction. Works will require the replacement of fendering to the jetty, with works undertaken from boats, and some dredging of the wharf to enable barge access. A conveyor will be constructed to allow excavated material to be loaded onto barges. At peak construction of excavated materials loading of barges may be required 24 hours per day. The conveyor will run from an excavated material handling point on the shore within the former Ford car park (disused), south of the River Thames, north of the wharf where it will connect to the barge loading point. Excavated material from Plumstead portal works will be delivered by lorry to the material handling point on the shore within the disused Ford car park south of the River Thames, where a small stockpile will be maintained and conveyor loading facilities, and lorry turning area will be provided. Site access for the construction of the conveyor and the refurbishment of the jetty will be via the new private access road to the Iron Mountain storage area. Once the handling site is in operation, excavated material will be brought to the site along Norman Road. For a period of 12 months the average lorry numbers accessing the site will be 240 per day. During this time there will be a peak period of approximately three months when the lorry numbers will be up to 260 accessing the site. At peak this equates to five or six 1,000 tonne barges moored at any one time. Norman Road is an un-adopted public highway which is in a very poor condition. Its current width is too narrow to carry the expected number of lorry movements and therefore temporary widening will be necessary.

3.10 Route Window SE7: Church Manorway Bridge

3.10.1 Overview of Route Window SE7 The proposed works within the route window comprise track realignment and the provision of two additional tracks within the existing railway corridor, the construction of new footbridges at Church Manorway and Bostall Manorway, the strengthening of Eynsham Drive Bridge, a 2m high noise barrier will be erected for the length of the route window on both sides of the railway, and the installation of OHLE equipment. The route window lies within LB Greenwich.

3.10.2 Permanent Works The NKL will be reconstructed and four tracked throughout the length of this route window. To accommodate the two Crossrail tracks in the centre, the Dartford and London bound tracks will be moved to the north and south respectively. Noise barriers of 2m in height (from track level) will be installed between the portal and Abbey Wood station. To accommodate four tracks and to be made fully accessible, the existing footbridge at Church Manorway will be demolished and replaced. Each side of the bridge will consist of four flights of stairs and four ramps, and will be 31m x 9.5m. The top of the bridge will be 8.4m above Church Manorway whilst the structure will be 34.4m long. The western extremity of the bridge will abut the western edge of Church Manorway.


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To accommodate four tracks and to be made fully accessible, the existing footbridge at Bostall Manorway will be demolished and replaced. Each side of the bridge will consist of four flights of stairs and four ramps, and will be 436m x 9.5m. The top of the bridge will be 8.6m above Mottisfont Road whilst the structure will be 34.4m long.

3.11 Route Window SE8: Abbey Wood Station

3.11.1 Overview of Route Window SE8 The proposed works within the route window comprise the reconstruction of Abbey Wood station, track realignment, the provision of two additional tracks within the existing railway corridor, and the installation of OHLE equipment. The route window lies within LBs Greenwich and Bexley.

3.11.2 Permanent Works The station will be rebuilt to accommodate terminating Crossrail services, and will include the partial rebuilding of Harrow Manor Way Bridge to accommodate the new platforms. The existing platforms will be extended to the east and west, and will become islands with new tracks constructed to the north and south. The existing station building will be demolished and replaced by a new station building and concourse constructed on a raft structure built above the tracks. It will be accessed at street level from Harrow Manorway Bridge, approximately 5m above platform level. A pair of escalators, a lift and a set of stairs will link the concourse to each platform and Gayton Road to the south of the station. A lift and a set of stairs will be provided to Felixstowe Road on the north side. The station building will be 24m deep by 40m wide and from street level, 8m high to the apex of the roof. The building will include a ticket office and staff accommodation. The NKL will be reconstructed to accommodate the two new Crossrail tracks in the centre and the rebuilt station at Abbey Wood. The Dartford and London bound tracks will be moved to the north and south respectively. To the east of Abbey Wood station, Crossrail trains will reverse and head back to Central London. Further east at a point 200m to the east of Parkway Primary School, the line will revert to the current double track alignment. West of Harrow Manorway bridge around Abbey Wood station a 2.5m high noise barrier will be constructed and west of the station this will reduce to 2m to join the noise barrier in Route Window SE7. East of Abbey Way elevated walkway there will be a 2m high noise barrier on the south side of the rail corridor to the end of the works. OHLE equipment will be installed throughout the route window.


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4 Site assessments

4.1 Route-wide impacts

4.1.1 Protective Measures Protective measures to mitigate the effects of ground settlement from tunnelling could require techniques, such as underpinning, which would need localised excavations. The location and details of any such measures that are required will not be determined within the timescale of the EIA, but they could partially or completely remove potential archaeological remains within the footprints of individual excavations.

4.1.2 OHLE masts OHLE mast construction would take place from Victoria Dock Portal to Abbey Wood turnback sidings. The impacts of this on archaeological resources would be mitigated by a procedure commencing with detailed desk based assessment to identify areas where either archaeological watching briefs would be necessary. This would exclude areas of deep cuttings where archaeological remains would not survive, and embankments higher than the depth of the mast foundations. The archaeological watching briefs would pay particular attention to areas where there is either a high potential for archaeological remains to survive beneath the existing permanent way, or where there is low to high potential for remains of high importance, with a more general coverage elsewhere. This fieldwork would be followed by appropriate post-excavation assessment, analysis, publication, and archiving. This methodology is consistent with the Incorporated Mitigation procedure. These measures would produce preservation by record, and result in no significant residual impact.


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4.2 Route Window SE1

4.2.1 Site 232 Blackwall Way Shaft

Site name Blackwall Way Shaft Site no. 232

Route Section South-East Window SE1

Location Blackwall Way, LB of Tower Hamlets

NGR 538670 180710

Proposed Works

Vent shaft construction and construction compound (‘worksite’).

Geology and topography

The site lies close to the foreshore of the Thames on a sequence of river alluvium, which overlies the Thames terrace gravel.

Baseline resources

• No Scheduled Ancient Monuments in the search area.

• The Crossrail site lies within the Blackwall and River Lea Area of Archaeological Importance. The Poplar Area of Archaeological Importance marginally encroaches on the search area to the north-west.

• High potential for palaeo-environmental remains within peat and alluvial sequences (including organic preservation and data on the interaction of changing river regimes and past environments). Evidence of a drowned “Palaeolithic forest”, probably Neolithic–Bronze Age, was found within these deposits at Blackwall, c 200m from the site and at East India Dock along with an elephant tooth (GLSMR 080735, 080890). Part of a mammoth tusk was also found locally (GLSMR 080732). Although these deposits were generally found (and removed) during construction of the East India and Poplar docks, the site itself seems to have escaped this level of disturbance.

• High potential for post-medieval industry and commerce associated with the Docks and Thames riverfront. Dockyard buildings and other structures occur throughout the search area (BCW92, BKW99, ASN97, GLSMR 222426). The southernmost of the former East India Docks constructed c 1806 lay adjacent, to the north-east of the Crossrail site (GLSMR 222356). The 19th-century dock road and warehouses of the West Quay (shown on the 1914 OS map) may have been within the site, with the original dock wall probably just beyond its eastern boundary. Further dock buildings shown on Horwood’s map c 1800 also appear to extend onto the site. The area between the Docks and the Thames was characterised by shipbuilding, Blackwall having a dock from at least 1660 (GLSMR 080966, 081556). The 1867 Ordnance Survey map shows a shipbuilding yard and dry graving dock (still extant) just to the south. The site itself was a railway goods depot and coal yard; with


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the lines of the London and Blackwall Railway, approaching the original 1840 terminus, crossing the southern part of the site.

• Low potential for prehistoric remains, including preserved timber structures, such as prehistoric trackways crossing the marshes (c 9 examples along Thames and tributaries, nearest: AWF98 & HW-FO94, 2.1km to south-west and east, respectively). There is also a low potential for individual prehistoric artefacts, eg Neolithic axes (GLSMR 110037, 112004, 112005, 112006). A Bronze Age sword and an axe were found in the vicinity of Bow Creek (the River Lea) to the north-east (GLSMR 061754, 061752).

• Low potential for Roman activity, suggested by artefacts from the search area, eg a miniature wine vessel (GLSMR 080835) and a jar (GLSMR 070380). A suggested watchtower (GLSMR 080896) is erroneous, based solely on extrapolation from a Roman structure at Shadwell, since reinterpreted as a mausoleum (Lakin 2002).

• Low potential for medieval and later settlement and related activity. Permanent occupation was mainly on higher ground to the north: Poplar High Street (GLSMR 081072) and St Leonard’s Street (IRS93, GLSMR 081594), Poplar being the main village (GLSMR 080964, 081007). Blackwall was a smaller settlement, closer to the Thames (and west of the Crossrail site) with a causeway to Blackwall Stairs, a landing place and ferry crossing (GLSMR 080966, 081555, 084287, 084288). These settlements, whilst present within the search area, did not extend to the Crossrail site. The main potential locally is for flood and land reclamation deposits (BCW92, BLK97).

Current status of land

South of the major carriageway (Aspen Way) and c 100m north of the Thames foreshore in an area of open, flat ground, currently a car park. The Reuters Building and a dock lie to the south.

Visited ?

Yes

Past impacts Land appears relatively undisturbed (former railway goods yard).

Importance of the baseline resources

• High importance: low potential for prehistoric timber trackways. Reasons: potential to contribute to published priorities including the research question “Understanding the relationship between the wooden trackways in the floodplain…” (Museum of London, 2002, 25); local and regional rarity of such finds to date, supporting data from other excavated trackways; good survival quality of organic remains within alluvium; and the vulnerability of the wooden structures.

• Moderate importance: high potential for palaeo-environmental evidence, and low potential for other prehistoric remains. Reason: formal identification within an Area of Archaeological Importance; and contribution to published priorities including the research question “Understanding the relationship between landscape, river … (Museum of London, 2002, 79); local rarity of in situ prehistoric remains; good survival quality particularly for organic materials within peat or alluvial deposits which are deposit types likely to


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preserve evidence of the historic environment and prehistoric remains.

• Moderate importance: high potential for industrial archaeology associated with the Docks and the Thames riverfront, including railway infrastructure. Reasons: formal identification within Area of Archaeological Importance. Docks, commerce, shipbuilding and the associated development of London’s early railways are a key feature of local and regional history and characteristic of the post-medieval landscape, with historical supporting data. Potentially good survival quality of substantial below-ground structures that are now rare. The diversity and group value of these multi-phase resources contribute to published priorities (eg Museum of London 2002: 74, 75, 82, 83, 88).

• Moderate importance: low potential for medieval and later occupation associated with Poplar and Blackwall villages. Reasons: formal identification; local rarity and historical supporting data. However, these settlements, whilst present within the search area, did not extend to the Crossrail site.

• Low importance: low potential for Roman artefacts. Reasons: low density chance finds, with limited contribution to published priorities.

Impact Construction of a vent shaft, and associated construction compound.

• Construction of basement box c 17m x 13m to house the shaft. The secant pile walls forming the box would extend down to –6.7mOD. Within this the basement would be excavated from ground level (c 5.50m OD) to c 0m OD. Note that this is approximately the level predicted for the base of the alluvium, c 5–6m below ground level. Impact: The basement would remove virtually all potential archaeological remains.

• Construction of c 9.0m dia. shaft inside the box, to a depth of 46m below ground level. The impact would be to completely remove any surviving archaeological remains within its footprint, below the basement construction level.

• The vent shaft boundary wall would be a masonry construction 2.2m high. Although foundation details are not yet available, the impact would be to partially or completely remove potential archaeological remains, depending upon whether strip footings or bored piles are used.

• Construction of ‘off-street’ hard-standing adjacent to the surface structure is unlikely to have an impact upon potential archaeological remains.


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• A construction compound, Blackwall Way Worksite, would be constructed around the shaft site.

○ A base for a tower crane, c 2m deep with piles at least c 10m deep, would partially remove potential archaeological remains, and completely remove them within the footprints of the piles.

○ General ground reduction (c 0.5m deep) and footings for compound accommodation (0.4–0.8m deep), and dewatering system (1.0m deep) may partially remove potential archaeological remains, including those of the former goods yard.

○ Temporary services (0.2m to 1.2m) are to be included. The likely impact of these works would be to partially remove potential archaeological remains within their individual footprints.

○ The impacts of any service diversions are unlikely to be determined within the timescale of the EIA, but are likely to partially remove potential archaeological remains.

Magnitude of impact before mitigation

Moderate with potential for a Significant impact

Additional information required?

Survey and geotechnical information on the depth of the alluvial deposits, and impacts from previous development, in order to refine the mitigation strategy.

Incorporated mitigation

The generic data gathering and mitigation measures, as described in the incorporated mitigation, would be applied to this Crossrail site.

Initially, DDBA and/or field evaluation would be required to establish levels of survival. This is likely to lead to further archaeological investigation, potentially to the base of the alluvium, c 5–6m below ground level, constituting preservation by record.

Residual impact after incorporated mitigation

None The incorporated mitigation measures would constitute preservation by record.

Site specific mitigation

None required

Residual impact after site specific mitigation

None

Significance of Residual Impact

Non-significant


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Engineering sources

Engineering Information provided by Crossrail

ES Scheme Description

Sources Historical / Archaeological sources

A 500m radius search of the GLSMR and LAARC

Greater London Industrial Archaeology Society (GLIAS) database v.2.65

Lakin, D, 2002 The Roman tower at Shadwell, London, a reappraisal

Researcher R W-B, PA, JDM, RF, RC, PM, JC

Date 11/01/2005


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4.2.2 Site 217 Limmo Peninsular vent shaft

Site name Limmo Peninsula vent shaft Site no. 217


Location Land adjacent to the Lower Lea Crossing, and south of Victoria Dock Road, LB of Newham

NGR 539480 180980

Proposed Works

Construction of a ventilation and emergency escape/access shaft initially used to launch the TBMs, with an access road and a construction compound (‘worksite’).

Geology & Topography

Beside the modern channel of the River Lea and within its alluvial floodplain. Borehole data suggests that alluvium in the locality may extend down from c 1.5m OD to c –3m OD. Past archaeological work suggests river scour has caused considerable erosion in this area, and the peat deposits known to the west and east of the site do not survive at this location (Sidell et al 2002, 97–102).

Considerable modern land raising has occurred on the Limmo peninsula: Crossrail borehole CH13 recorded a 4.6m thickness of modern land raising at the site of the vent shaft, and other boreholes in the vicinity also show c 5m of ‘brick and concrete rubble’, increasing to c 9m in one borehole which is likely to have been within a 19th-century dock.

Baseline resources

• No Scheduled Ancient Monuments are present within the search area.

• The Crossrail site and majority of the search area fall within an Archaeological Priority Area (LB Newham). The remainder of the search area falls within an Area of Archaeological Importance (LB Tower Hamlets).

• High potential for industrial archaeology: the site was occupied from 1846 to 1912 by the Thames Ironworks and Shipbuilding Company, and its predecessors, the largest shipbuilder on the Thames. Subsequently, the 1916 Ordnance Survey map shows the site occupied by large ship repair yards, including extensive buildings, a dock and slipways and an internal railway system. Silvertown Way c 75m to the east of (outside) the Crossrail site dates to 1934 and is Britain’s first elevated concrete road. It was constructed by Dorman Long and comprises a partially extant road viaduct over the railway, Victoria Dock Road and the entrance to the tidal basin (GLIAS database).

• Moderate potential for prehistoric and later palaeo-environmental remains within alluvial sequences, relating to the depositional environment at the confluence of the River Lea and River Thames.


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• Moderate potential for Roman and later river management and land reclamation. Roman flood defences along this stretch of river, continued through later periods (GLSMR 081052), with a possible post-medieval causeway on the Thames foreshore (GLSMR 084790, not extending to the Crossrail site) and 19th-century reclamation (ORP96).

• Low potential for prehistoric artefacts: any prehistoric remains are thought to have been removed by the shifting channel of the Lea.

• Low potential for medieval manor of Covelees (GLSMR 061808) possibly near the mouth of the river Lea, and for isolated medieval artefacts, eg a lance head and a spur (GLSMR 061767, 081780, 061780).


Open ground with dense scrub and some woodland lying between the North London Line and the Lea (Bow Creek) to the west. The ground is uneven and is covered in dumped material that has raised the ground level by c 4–5m in the area of the site. See also topography, above, for modern land raising.

Visited ?

Yes

Past impacts Construction of the former shipyard. Considerable meandering of the River Lea during the Holocene is likely to have removed the majority of early prehistoric deposits in this area (eg no Neolithic/Bronze Age peat deposits are known to survive).


• Moderate importance: moderate potential for palaeo-environmental evidence, and low potential for prehistoric artefacts or other remains. Reasons: as per Site 232, above.

• Moderate importance: moderate potential for Roman and later river management and land reclamation. Reasons: formal identification within an Area of Archaeological Importance; local rarity of in-situ remains; historical supporting data; good survival quality of a deposit type likely to preserve organic materials (eg timber structures) and contribution to published priorities (eg Museum of London, 2002: 79, 80, 81, 86).

• Moderate importance: low potential for medieval manor. Reasons: high local rarity of such evidence, historical supporting data.

• Moderate importance: high potential for 19th/20th-century industrial archaeology, the Thames Ironworks. Reasons: ship building and repair are a key feature of the history of the area, including social history, historical supporting data and associations, such as the building of Britain’s first ironclad warship, the Warrior.

• Low importance: low potential for isolated medieval artefacts. Reasons: isolated finds with limited contribution to published priorities.


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Impact The proposed works include the construction of a vertical shaft and the extension of the DLR access road to the shaft. As a result of the c 4.6m depth of modern land raising across the site, works other than the shaft would be too shallow to have an impact on archaeological remains. In detail the impacts are:

• A shaft for construction, ventilation and emergency escape. The shaft would have an internal diameter of 25m descending to a formation level 42m below ground level, and would employ diaphragm walls. The impact of the construction of the shaft would be to completely remove all potential archaeological deposits.

• All other works, such as surface structures, hardstanding, ground levelling, and those in the construction compound, the Limmo Worksite, would have no impact.

• Changes in groundwater level have been predicted at this site. The potential impact, if any, cannot be adequately quantified due to a lack of detailed information; in particular on present groundwater regime and on the nature of any surviving archaeological remains. However, there are no known resources on the site of a type which might be adversely affected.


Moderate, with potential for a Significant impact


Cartographic and documentary evidence for the 19th/20th-century shipyards would be required to in order to refine the mitigation strategy.


The generic data gathering and mitigation measures, as described in the incorporated mitigation, would be applied to this Crossrail site. DDBA and/or field evaluation would be required in order to refine the mitigation strategy. In particular, geoarchaeological evaluation would probably be required.

This may to lead to archaeological excavation, and/or a geo-archaeological watching brief, constituting preservation by record.


None

The incorporated mitigation measures would constitute preservation by record.


None required


None


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Non-Significant

Engineering sources


ES Scheme Description Sources Historical /

Archaeological sources

A 500m-radius search of the GLSMR and LAARC


Researcher R W-B, PA, RC, RF, PM, JC

Date 11/01/2005


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4.3.1 Site 219 Victoria Dock Portal

Site name Victoria Dock Portal Site no. 219


Location Principally along the existing North London Line, from east of DLR Royal Victoria Station to east of NLL Custom House station, LB of Newham.

NGR 540460 180910

Proposed Works

Cut-and-cover tunnel portal, emergency access/passenger evacuation shaft at tunnel eye, temporary DLR realignment, diversion of services.


On alluvium east of the confluence of the Lea and Thames, 2–3m thick peat deposits are known in this area, over gravel and sand that rises towards the east. Ground level adjacent to the site is 1.6m OD.

Baseline resources

• No Scheduled Ancient Monuments within search area.

• The site is located within an Archaeological Priority Area. • High potential for prehistoric and later palaeo-environmental

remains within peat sequences and palaeo-channels, as per Site 232, above (FRU01, HW-AH96, PRG97, BWC96; GLSMR 062295, 062475, 062476, 062493, 062494, 062495, 062650, 062651).

• High potential for industrial archaeology associated with Royal Victoria Docks, just to the south, which opened in 1855 (HW-AH96, GLSMR 221639, 062197, 062674, 062675, 062767). The 1894 Ordnance Survey map indicates a range of structures adjacent to the work site, including substantial warehouses, the Custom House and extensive railway goods yards, lying behind the main northern quayside. The yards connected to the main infrastructure of the North Woolwich Railway, which opened in 1847. These lines took much the same route as today and included a station on the site of the existing one (NLL: Custom House). In 1918 an additional 5486m of sidings were laid near Customs House Station. The 1894 Ordnance Survey map also shows the Royal Victoria & Albert Docks Cut (used for drainage purposes), between the sidings to the south of Customs House Station and the railway line adjacent to Victoria Dock Road. The 1950s Ordnance Survey map shows the Cut still in existence.

• Moderate potential for prehistoric timber trackways (nearest is HW-FO94, 900m to south-east, also PRG97) and occupation near the boundaries of the dry eyots/islands and wetlands (possible occupation: GLSMR 062137), and isolated artefacts, as per Site 232, above.


34

• Moderate potential for below-ground remains of the site of the medieval manor house of Sudbury. The SMR records the possible site of the manor house at Prince Regent Lane, in the eastern section of the site (SMR 061790) and actually in Route Window SE3. The manor (estate) of Sudbury was formed from land owned by Peverel in West Ham in AD 1100–1135, called ‘Peverel’s Moiety’. The estate was ceded to the Crown. The last documented reference was in 1545 under the alias Abbey Place. It is presumed to have been subsequently merged with the manor of West Ham. The exact location of the manor house is not known and its position within the site is based on field name evidence (‘Sudburyfield’).


Railway land, with existing tracks on a low embankment. Open ground to the south of the tracks would also be acquired.

Visited ?

Yes

Past impacts Construction of the dock buildings, the Royal Victoria & Albert Docks Cut, and railway infrastructure.


• High importance: moderate potential for prehistoric timber trackways. Reasons: as per Site 232, above.

• Moderate importance: high potential for palaeo-environmental evidence. Reasons: as per Site 232, above.

• Moderate importance: moderate potential for the site of medieval manor house of Sudbury. Reasons: potential to contribute to published priorities (Museum of London, 2002, 25)

• Moderate importance: high potential for industrial archaeology, including railway infrastructure and a drainage cut. Reasons: as per Site 232, above.

Impact The portal works consist of the tunnel approach ramp within a retained cut, a length of cut-and-cover tunnel, and a shaft at the tunnel eye. The shaft would be used during construction for the removal of TBMs and on completion would provide access for emergency services and passenger escape facilities. A construction compound (‘worksite’) would extend along the proposed route and service diversions are required. The impacts are:

• Tunnel eye incorporating a shaft for construction, and for access for emergency services and passenger escape facilities. The shaft would measure 28m by 20m and employ diaphragm walls descending to c –20.8m OD. Formation level for the base slab would lie at c –10m OD. The impact of the construction of the shaft would be to completely remove potential archaeological remains.

• Excavation of a 60m-long cut-and-cover tunnel, between the open cut and the shaft. The toe of the diaphragm walls would ascend eastwards in steps from c –13m to –11.5m OD and the base slab formation level from c –9.4m to c –7.5m OD. The impact would be to completely remove potential archaeological remains.


35

• Excavation of a 190m-long tunnel approach ramp within an open cut retained by diaphragm walls. The toe of the diaphragm walls would ascend eastwards in steps from c –11.5m to c –6.75m OD and the base slab formation level from c –7.5m to c –2.6m OD. The impact would be to completely remove potential archaeological remains.

• Excavation of a 60m-long approach ramp within an open cut retained by steel sheet piling walls. The toe of the sheet piles would ascend eastwards from c –8.40m OD to c –5.90m OD and the base slab formation level from c –2.6 to c –1.16m OD. The impact would be to completely or partially remove potential archaeological remains.

• A construction compound (Victoria Dock/Custom House Worksite) serving both this site and Custom House Station (Site 220, below). It extends from east of the Prince Regent DLR station along the cutting, westwards to Royal Victoria DLR station (including the ExCel car parks south of the railway and two small areas on the north side of Victoria Dock Road near the junction with Freemasons Road). Impact: although details are not yet available, preparatory ground reduction, hard standing and footings for plant, accommodation and a site footbridge (c 1m) may partially remove potential archaeological remains. A tower crane base, supported on piled foundations, may completely remove such remains (locally).

• Major service diversions: the Royal Docks surface water sewer, Royal Docks foul sewer, and local surface water sewer diversions would comprise tunnelling accessed by two 18m deep by 10m diameter shafts and three 16m deep by 3m diameter shafts. The service tunnels would lie beneath the alluvium and therefore not have an impact. The impact of the shafts would be to completely remove surviving archaeological remains within their footprints at Site 219 and Site 220.

• Other service diversions, including a gas main. Although details are not currently available, new service trenches are likely to partially remove surviving archaeological remains.

• The temporary diversion of DLR between Royal Victoria Station and Custom House Station to run south of the current route through the proposed worksite may have the potential to remove archaeological remains. There would be a duct under the tracks. The laying of track should have no impact on potential archaeological remains, but associated works might partially remove any such remains.

• Laying down of an area of hard standing between the Excel Car Park and the DLR is only likely to have an impact on any surviving remains of the late 19th-century railway sidings.


36

• The removal of the existing North London Line track on the line of the Victoria Dock Portal would probably have no impact on potential archaeological deposits.

• Changes in groundwater level have been predicted at this site. The potential impact, if any, cannot be adequately quantified due to a lack of detailed information; in particular on present groundwater regime and on the nature of any surviving archaeological remains. However, there are no known resources on the site of a type which might be adversely affected, although there is potential for waterlogged organic remains.


High, with potential for a Significant impact





Initially DDBA and/or field evaluation would be required to establish levels of survival. This is likely to lead to further archaeological investigation, potentially to the base of the alluvium, constituting preservation by record.




None required


None


Non-Significant

Engineering sources


ES Scheme Description Sources

Historical / Archaeological sources

A 750m-radius search of the GLSMR and LAARC.


Researcher HK, PA, RC RF, PM, JC

Date 13/01/2005


37

4.3.2 Site 220 Custom House Station

Site name Custom House Station Site no. 220


Location Custom House Station, Victoria Dock Road, LB of Newham

NGR 540950 180950

Proposed Works

Removal of whole of existing NLL station and trackwork, the construction of a new elevated station with island platform and tracks at ground level, with access via an extension to an existing walkway to the south and a new footbridge across Victoria Dock Road and entrance building on the corner of Freemason’s Road. The construction of a temporary worksite on north side of Victoria Dock Road followed by a new building. Diversion of Royal Docks Surface Water Sewer and Royal Docks Sewer.


On alluvium east of the confluence of the Lea and Thames. 2–3m thick peat deposits are known in this area, over gravel and sand that rises towards the east. The site lies at c 1.55m OD.

Baseline resources


• The site is located within an Archaeological Priority Area.

These works fall within the same overall area as Site 219, above, and so the potential for archaeological resources is similar:

• High potential for prehistoric and later palaeo-environmental remains (see Sites 232 and 219, above).

• High potential for 19th/20th-century industrial archaeology. The 1894 Ordnance Survey map shows the Royal Albert and Victoria Docks Cut (used for drainage purposes) to the west of the Custom House Station. The Cut was located between the sidings to the south of the station and the railway tracks adjacent to Victoria Dock Road. In 1918, an additional 5486m of sidings were laid near Customs House Station. The 1950s Ordnance Survey map shows the Cut still in existence. The station itself was largely redeveloped in c 1980, although a possible early 20th-century footbridge providing access across the tracks to Custom House is still extant (GLIAS database).

• Moderate potential for prehistoric timber trackways, occupation, and isolated artefacts (see Sites 232 and 219, above).

• Moderate potential for below-ground remains of the site of medieval manor house of Sudbury (see Site 219, above).


38


The existing railway is on a low embankment and Custom House station is also above street level. A recreation ground and pond to the north of Victoria Docks Road and open land to the south would also be acquired. Inspection of the eastern end of the Victoria Dock/Custom House Worksite revealed no above ground remains. There are trees largely alongside and in between roadways, allotments to the north and open land (Excel Site) to the south. Most of the area has been landscaped into roads and turf with embankments against the roads.

Visited ?

Yes

Past impacts Railway land, with existing tracks on a low embankment. Open ground to the south of the tracks would also be acquired.


• High importance: moderate potential for prehistoric structures such as timber trackways and occupation. Reasons: as per Site 232, above.


• Moderate importance: high potential for industrial archaeology, including canal and railway infrastructure. Reasons: as per Site 232, above.

• Moderate importance: moderate potential for the site of medieval manor house of Sudbury. Reasons: as per Site 219, above.

Impact Demolition of the existing station and buildings to the west of it. The new station would include a main concourse area and ticket office (raised at bridge level over the tracks) and an island platform (at ground level; accessed via stairs, escalator and a lift at the west end, with escape bridges at the middle and east end of the platform). The impacts are:

• Excavation and other ground works. An area running the length of the track for c 375m, including the total area of the station, would be excavated to a depth of c 1.5m below ground level, increasing to 3m in the vicinity of Victoria Dock Portal. Subsequent works here include track laying, construction of 245m-long island platforms, pad foundations for some of the lifts/stairs/escalators, and ground disturbance within construction compounds. The impact of these works would be to partially or completely remove potential archaeological remains within the excavated area (see below for the impact of piling).

• Piled foundations. Contiguous piled retaining walls are required along the full length of the excavated track. The high-level station building, footbridges, some of the lifts/stairs/escalators and an extension of the existing ExCel exhibition centre walkway, would also have piled foundations. Piling would increase the impact within the area of ground reduction (above) to complete removal of any surviving remains locally, along the line of the retaining walls and at individual pile and cap positions elsewhere.


39

• Station entrance building at Freemason’s Road and Victoria Dock Road, constructed following demolition of the former public house, ‘The Barge’(c 1862). The new building would have piled foundations. Stairs, escalators, a lift, and an associated plant room, would be supported on pad foundations. The impact would be to partially or completely remove potential archaeological remains locally, within the areas of individual foundations.

• Major service diversions: see Site 219, above. • Other service diversions (Trunk Water Pipe, Sewer, BT cables,

Transco pipe). Details will not be available within the timescale of the EIA, but these works are likely to partially remove potential archaeological remains.

• Ramp up from south side of Victoria Dock Road to bridge level. The impact of the 1.5m deep ramp footings would be to partially remove potential archaeological remains.

• Construction compound: see Site 219, above. • A lay-by area and cycle park on the north side of the Victoria

Dock Road just west of junction with Freemason’s Road would be unlikely to have any impact on potential archaeological deposits.


Moderate with potential for a Significant impact.




The generic data gathering and mitigation measures, as described in the incorporated mitigation, would be applied to this Crossrail site. Initially DDBA and/or field evaluation would be required to establish levels of survival. This is likely to lead to further archaeological investigation, potentially to the base of the alluvium, constituting preservation by record.




None required


None


Non-Significant


40

Engineering sources


ES Scheme Description Sources Historical /

Archaeological sources

A 750m-radius search of the GLSMR and LAARC.


Researcher HK, PA, RC, RF, PM, JC

Date 13/01/2005


41


4.4.1 Site 412 Connaught Tunnel

Site name Connaught Tunnel Site no. 412


Location The site is located in the London Borough of Newham, between Prince Regent station and the Victoria Dock Road at its northern end and Silvertown station and Connaught Road/Factory Road at its southern end. The c 550m-long Connaught Tunnel (also known as the Silvertown Tunnel) presently carries the North Kent Line beneath Connaught Passage which separates the Royal Victoria Dock to the west and the Royal Albert Dock to the east.

NGR 541050 180945 to 542060 180110

Proposed Works

Refurbishment of tunnel including remedial structural repairs, replacement of drainage system and clearance of vegetation at tunnel approaches. Three construction compounds (two shared with other Crossrail sites).


On reclaimed alluvial floodplain of the River Thames, c 700m to the north of the Thames and c 2km east of its confluence with the River Lea. This area was dry land intersected by channels in the Mesolithic period, and became wetland during the Neolithic, following sea level rise. Reclamation began in the medieval period. In the late 19th to early 20th century two huge docks were constructed and the excavated alluvium redeposited as a general levelling of the surrounding land.

Recent geoarchaeological investigations suggest that Connaught Passage in the centre of the site was located within a low channel between two known eyots (sand/gravel islands) situated, respectively, in the northern part of the site near Custom House, and in the southern part, west of Silvertown station. The top of the gravel is likely to lie between c –3 and –1m OD in the area of Connaught Passage, rising to c –1 in the north and south. Peat deposits 2–3m thick are known in this area.

Baseline resources


• The site is located within an Archaeological Priority Area.

• Connaught Tunnel was constructed in 1878, when the Canning Town to North Woolwich railway line (now part of the North London Line) was rerouted to pass in a tunnel beneath the passage between the two docks, and so avoid delay to trains when ships were passing. Due to the relatively steep tunnel gradient (1 in 50), some freight trains continued to cross at ground level using the old Connaught Road swing bridge, a hydraulically operated bridge which was replaced in 1987–90. In 1937, the depth of the Passage


42

was increased from 28 to 31 feet and in 1958 its width was increased from 84 to 100 feet (Royal Docks Trust website). The line was converted to a single track in 1986.

• The southern end of the site lies within what was the churchyard of St Mark’s Anglican church. The Grade II listed church was built in 1861/62 by Samuel Saunders Teulon and lies immediately outside of the Crossrail site. The churchyard was never used for burials. See Site 222 below.

• High potential for prehistoric and later palaeo-environmental remains within alluvial sequences, including organic preservation and data on the interaction of changing river regime and past environments (NWH01).

• High potential for 19th/20th-century industrial archaeology. From the late 19th century, land adjacent to the northern end of the site was occupied by a number of sidings associated with Custom House Station and the docks. Connaught Passage, in the centre of the site, was built as a water link connecting two vast linear docks, the c 1.5km-long Royal Victoria Dock to the west, constructed in 1855, and the c 2km-long Royal Albert Dock to the east, which opened in 1880. The Royal Victoria Dock was the first dock built expressly for steam ships and was connected directly to the railway system. The original entrance to the dock was via a lock and tidal basin at its western end. The dock was extensively rebuilt 1935–1944 including the construction in 1937 of the new North Quay, which replaced the five finger-jetties of the original Victoria Dock. Rather than the multi-storey warehouses of London’s earlier docks, the Royal Albert Dock had single storey transit sheds lining each wharf, the emphasis being on a fast turn around of goods. The Ordnance Survey 2nd edition 25” map of 1894–6 shows several non-extant buildings marked ‘Engine House’ at the end of a railway siding running along the northern edge of the Royal Albert Dock, within the northern half of the proposed Connaught Tunnel Worksite. It also shows the north-western corner of a large non-extant building, marked ‘Engine Works’ within the footprint of the southern half of the Worksite. It is possible that footings of these structures survive below-ground.

• High potential for the below-ground remains of a vicarage (see Site 222 below).

• Moderate potential for remains within the peat deposits of Neolithic to Bronze Age wetland activities, especially close to the palaeochannels and sand/gravel eyots, including timber structures such as trackways. The nearest excavated trackway is PRG97, 650m to the north-west.

• Moderate potential for Roman and later flood management, land reclamation and economic activity. The Ordnance Survey 1st edition map of 1870 pre-dates the docks and shows the area consisting of open reclaimed marsh, crossed by a networks of


43

drainage ditches enclosing individual parcels of land. The marsh was probably reclaimed in stages through the construction of a series of sea walls. The marsh would have been very important economically for activities such as animal husbandry, arable cultivation, pottery and salt manufacture. This potential includes the possible presence of wharfs and hulked vessels along former creeks, seasonal embankments used to protect summer crops, sheep shelters, and possible secondary permanent and seasonal settlement in the form of homesteads, typically located on higher ground or artificially raised areas in the marsh.

• Moderate potential for below-ground remains of the site of medieval manor house of Sudbury, within the Victoria Dock/Customs House Worksite (see Site 219 above).


Only the western and eastern ends of the site, ie the construction compounds at each end of the tunnel (the eastern end of Victoria Dock/Custom House Worksite and the western end of Silvertown Worksite) were examined on the site visit. No above-ground remains of archaeological interest were noted. The trees (to be removed) at the northern end of the site are largely alongside and in between roadways. There are allotments to the north and open land (Excel Site) to the south. Most of the area has been landscaped into roads and turf with embankments against the roads. The former church at the southern end of the site lies within a locked compound (not accessed). To the east of the church, where the Vicarage was situated, lies a hauliers yard. To the north of the church, where the proposed Silvertown Worksite is situated, is open unmade ground currently used as a car parking area. To the south of the Church, a dual carriageway (North Woolwich Road to the north and Factory Road to the south) is bisected by the railway line. At its western end, former lines have been replaced by trees which define another area allocated for a works compound / storage area.

Visited ?

Yes

29.10.04

Past impacts Excavation of the docks down to the London Clay will have completely removed any earlier archaeological remains. There is a possible past impact of unknown extent from the tunnel construction. The presence of a blanket of redeposited alluvium from the docks’ excavation is anticipated around the periphery, based upon evidence from previous investigations in the area. The tunnel structure suffered bomb damage during the Second World War and was repaired shortly afterwards.


• High importance: moderate potential for prehistoric structures such as timber trackways and occupation. Reasons: as per Site 232, above.

• Moderate importance: moderate potential for palaeo-environmental evidence. Reasons: as per Site 232, above.


44

• Moderate importance: moderate potential for Roman, medieval and flooding management, land reclamation and economic activity. Reasons: potential to contribute to published priorities (Museum of London, 2002, 25)

• Moderate importance: moderate potential for the site of medieval manor house of Sudbury. Reasons: as Site 219 above.

• Moderate importance: high potential for industrial archaeology, including docks and railway infrastructure. Reasons: as per Site 232, above.

• Low importance: high potential for below-ground remains of the footings of a late 19th-century (possibly earlier) vicarage.

Impact Details of the works will not be available within the timescale of the EIA. Replacement of the drainage system, possible major utility diversion, clearance of vegetation, and ground disturbance within three construction compounds.

• Replacement drainage system. The new drainage system would require excavation along the entire length of the tunnel and its approaches. Within the tunnel, the drainage trench would be lowered by 0.6m and the impact would be to partially remove potential archaeological remains. Outside the tunnel, the new system could be installed in the same place as the existing and would therefore have no impact upon potential archaeological remains.

• Tunnel works. Rail levels would be lowered by 0.6m for the required clearance. The new concrete tunnel floor would be pinned to the existing Victorian brickwork. The central wall in the central section (where there is a twin bore brick tunnel) may be underpinned. The existing arches of the remaining tunnel section (dated to 1878 or later) would be removed and replaced by new struts. It is not known whether the 3ft increase in depth in 1937 included breaking out the base of the original tunnel. Impact on historic fabric of tunnel: removal of brick arches (possibly original). If the base of the tunnel has already been replaced, track lowering would have no additional impact.

• Possible major utility diversions. Details will not be available within the timescale of the EIA, but if of substantial depth, these are likely to partially or completely remove potential archaeological remains.

• Three construction compounds. These comprise:

○ The Connaught Tunnel Worksite, located within Connaught Passage, on either side of the Swing Bridge.

○ Victoria Dock/Custom House Worksite: see Site 219 above.

○ Silvertown Worksite, shared with Site 222, below.


45

Although details are not yet available, works such as preparatory ground reduction, and footings for plant and accommodation, etc, would partially remove potential archaeological remains.


Low with potential for a Significant impact.


Survey and geotechnical information (particularly on the depth of alluvial deposits and construction of the Connaught Tunnel) in order to refine the mitigation strategy.


The generic data gathering and mitigation measures, as described in the incorporated mitigation, would be applied to this Crossrail site. Initially, DDBA and/or field evaluation would be required to establish levels of survival.



None


Existing historic Connaught Tunnel: initial structural appraisal of the historic fabric, in order to determine the appropriate level of recording from those specified by RCHM(E) 1996, to constitute preservation by record. This is likely to take the form of a photographic record in advance of works followed by an archaeological watching brief during works.


None


Non-Significant

Engineering sources






Ordnance Survey 1st edition 6” map, 1882

Ordnance Survey 2nd edition 25” map, 1894–6

Researcher JC Date 11/01/2005


46

4.4.2 Site 222 Silvertown

Site name Silvertown Site no. 222


Location Connaught tunnel east portal to North Woolwich portal (including the existing Silvertown Station).

NGR 542500 180040

Proposed Works

Demolition of the existing NLL station, and removal of the pavement capping the platform. Demolition of the Tate & Lyle bridge.


265m to the north of the Thames on floodplain peat and alluvium (reclaimed marshland). This area was dry land intersected by channels in the Mesolithic, becoming wetland during the Neolithic. Former sand/gravel eyots are present in the area. Ground level in the vicinity is 2.1m OD.

Baseline resources


• The site lies within an Archaeological Priority Area. • The existing station dates from the mid 20th century, post-1921,

and probably post-war. The original Silvertown station (built in 1863 and shown on the 1882 Ordnance Survey) lay between the GER Woolwich Branch (south of Connaught Road) and the later spur to the west (on the northern side of Factory Road) outside the Crossrail site.

• Silvertown Worksite lies within what was the churchyard of St Mark’s Anglican church. The Grade II listed church was built in 1861/62 by Samuel Saunders Teulon and lies immediately outside of the Crossrail site. It closed in 1972 and was damaged by fire in 1981. It was later restored and converted to house the collections of the Passmore Edwards Museum. It never fulfilled this function and remained disused for many years, only recently becoming the home of the Brick Lane Music Hall project. The churchyard was apparently never used as a burial ground, the East London Cemetery serving this purpose.

• High potential for prehistoric and later palaeo-environmental and organic evidence within peat and alluvial sequences, reflecting past river regime and local environmental change. (WW-PS93, BAJ00, NWH01, DLA02, WWA02).


47

• High potential for industrial archaeology (Site code HW-AH96 and GLSMR 062197). The area was first developed following the opening of the North Woolwich Railway in 1847 and the subsequent construction of the Victoria and Albert Docks to the north (c 1880). The Thames riverfront zone became heavily industrial, the manufacture of soap, jam and sugar being prominent locally. Several of the factories had their own railway sidings. The 1893 Ordnance Survey map shows an India Rubber, Gutta Percha and Telegraph Works south of Connaught Road/Factory Road. This was for the manufacture of submarine cables and had formerly been S.W. Silver’s Waterproof Clothing Works (c 1852) from which Silvertown took its name. It eventually covered 17 acres, employing 3000 people. The 1869 Ordnance Survey map has the Albert Iron Works and Victoria Docks Gas Works to the east, between Albert Road and the river.

• High potential for the below-ground remains of a vicarage shown on the Ordnance Survey 25” map of 1894–6 at the southern end of the site, within the Silvertown Worksite (below). The vicarage was presumably associated with St Marks Church (above).

• Moderate potential for Mesolithic dry land and riverside activity associated with the eyots and channels; possibly within the basal sands and silts, below the main peat bed.

• Moderate potential for Neolithic to Bronze Age remains within the peat deposits, including possibly timber trackways linking eyots, across the silted-up channels (nearest example is HW-FO94, 1.1km to the west).

• Moderate potential for Roman and later flooding, river management and land reclamation (GLSMR 062684). Alluvial deposits in the area have shown evidence of medieval occupation, documented floods and abandonment of the area in the early 15th century (Site code AET01). As late as the 19th century the area north of Albert Road was open, low-lying land, intersected by streams, drainage ditches and flood embankment walls.


Railway land: the existing single track is at street level. The area of the Silvertown Worksite lies to the north of a former church at the southern end of the site and lies within a locked compound (not accessed). To the east of the church, where the Vicarage was situated, lies a hauliers yard. To the north of the church, where the proposed construction compound is situated, is open unmade ground currently used as a car parking area. To the south of the church what appears to be a dual carriageway (North Woolwich Road to the north and Factory Road to the south) is bisected by the railway line. At its western end, former railway lines have been replaced by trees which defines another area allocated for a works compound / storage area.

Visited ?

Yes


48

Past impacts Existing station and railway, 20th-century bombing, 19th-century industry.


• High importance: moderate potential for Mesolithic, and Neolithic to Bronze Age activity, including possible timber trackways, and occupation. Reasons: as per Site 232, above.


• Moderate importance: high potential for industrial archaeology, including railway infrastructure. Reasons: as per Site 232, above.

• Moderate importance: moderate potential for Roman and later flooding, river management and land reclamation. Reasons: as per Site 217, above.

• Low importance: high potential for below-ground remains of the footings of a late 19th-century (possibly earlier) vicarage.

Impact The demolition of the existing 20th-century station and removal of the capping to the platforms would have no impact on archaeological resources. Demolition of the private bridge serving the Tate and Lyle works, a steel structure of 20th-century date. This would have no impact upon archaeological remains. A construction compound for storage and parking, the Silvertown Worksite would also have no impact. There are no other works.


None


Not required


Not required


None


Not required


None


Non-Significant


49

Engineering sources






Kirkpatrick, 1921 Map of Port of London Authority Docks

Ordnance Survey map of 1893

Researcher HK, PA, NJE, PM, JC

Date 21/12/04


50


4.5.1 Site 225 North Woolwich Portal & Vent Shaft

Site name North Woolwich Portal Site no. 225


Location Land between Albert Road and Factory Road, between the junctions with Tate Road and Henley Road, North Woolwich, LB of Newham. Also land on west side of Henley Road and east side of Store Road.

NGR 542698 180003

Proposed Works

Tunnel portal, Ventilation & Intervention shaft, worksites and service diversions.


The site is situated on floodplain peat and alluvium (reclaimed marshland) 100m to the north of the River Thames. This area was dry land intersected by channels in the Mesolithic, becoming wetland during the Neolithic and former sand/gravel eyots exist in the area. The site may include a palaeochannel (the former Ham Creek). The 1869 Ordnance Survey shows a stream channel crossing the site and discharging into the creek south of Albert Road. An 1805 map shows this creek as having been larger and extending further inland, suggesting the presence of a palaeochannel from a minor tributary of the Thames. Ground level adjacent to the site is 1.2m OD.

Baseline resources


• The site lies within an Archaeological Priority Area. • High potential for palaeo-environmental evidence, as per Site 222,

above (BAJ00, WWA02). • Moderate potential for industrial and railway archaeology,

generally as per Site 222, above (also GLSMR 800110, 071475). North Woolwich station (the original 1847 terminus) is now a railway museum and elements of it are listed. It originally served the Woolwich ferry and to the south (beyond the Crossrail site) there is also an ornamental pagoda, the entrance to a 1902 foot tunnel under the Thames.

Also associated with the railway, to the east of the station, was a pavilion and ornamental pleasure gardens including a maze, ballroom, dining saloon, fairground and music hall theatre (Royal Pavilion Gardens c 1852, shown on the 1869 Ordnance Survey map, now a public park).

To the west of the station (TQ4288 7997) is a late 19th/early 20th-century bridge across the railway from Albert Road to Factory Road. It comprises cast-iron columns, wrought iron trellis work, with open wooden stairs (GLIAS database). Standard Industrial Estate, on the south side of the line, was originally Henley’s


51

Telegraph Works Co. Ltd., and from 1853 submarine cables and electrical apparatus were manufactured here (GLIAS database).

• Moderate potential for Mesolithic dry land and riverside activity, as per Site 222, above.

• Moderate potential for remains of Neolithic to Bronze Age wetland activities, including timber trackways, as per Site 222, above. The nearest trackways are PRG97 and HW-FO94, 1.6km to the north-west and 1.8km to the west, respectively.

• Moderate potential for Roman and later flooding, river management and land reclamation, as per Site 222, above. Roman land management includes dumped occupation debris, postholes and ditches (Site code HE-MS96, BAJ00, DLA02, WWA02; GLSMR 061803, 061818, 062640, 062641). Evidence of medieval occupation such as farmsteads has also been found on adjacent sites (Site code AET01, HE-MS96). The administrative anomaly of Woolwich Detached (in Essex) and Woolwich in Kent is of early medieval origin, when the manorial estate extended to both sides of the river, suggesting control of the ferry point. It is referred to as a royal ferry in 1320, but had clearly operated in previous centuries, when tithes were paid to Lesnes Abbey.


The land is generally at grade, consisting of the station and a single railway track, separated from a large open area to the south-east by a band of trees, with an industrial estate on the west side of Henley Road.

Visited ?

Yes (original scheme)

Past impacts Underlying deposits will have been partly truncated by the existing railway and, in the area of the proposed work sites, by 19th- and 20th-century industrial buildings, although some of these features may themselves constitute archaeological resources.


• Moderate importance: moderate potential for Mesolithic, and Neolithic to Bronze Age activity, including occupation and palaeo-environmental evidence. Possible timber structures such as trackways would be of high importance. Reasons: as per Site 232, above.

• Moderate importance: high potential for industrial archaeology, including railway infrastructure. Reasons: as per Site 232, above.

• Moderate importance: moderate potential for Roman and later flooding, river management and land reclamation, and for medieval occupation. Reasons: as per Site 217, above.

Impact The proposed portal works consist principally of the tunnel entrance (eye) and shaft, approached by an extensive length of cut-and-cover tunnel approach ramp. The shaft would be used for construction of the running tunnels and on completion would become an intervention and evacuation point. There would also be a construction compound (worksite). Moving eastwards, the impacts are:


52

• 713m-long tunnel approach ramp of four sections. It would be approximately 16m deep in the vicinity of the BT satellite station.

○ 101m-long retained cut with temporary sheet piles and permanent concrete U-section ground support.

○ 425m-long retained cut with diaphragm walls. ○ 127m-long cut-and-cover tunnel with diaphragm walls. ○ 60m-long cut-and-cover tunnel, with diaphragm walls. The impact of construction of the first three sections of the

approach ramp would be to completely remove all surviving archaeological remains (excluding the final section of graded ballast from ground to embankment level).

• Tunnel eye incorporating a shaft for construction, intervention and excavation. The shaft would measure c 21m by 30m (internally) and employ diaphragm walls descending c 31m. The impact of the construction of the tunnel eye would be to remove completely all surviving archaeological remains.

• Major service diversions:

○ Reconstruction of sewer inlet to pumping station at Albert Road: open cut trench to a depth of 5m with sewer carried over the railway.

○ The diversion of the Royal Docks sewer under Factory Road to south of the road: tunnel with three shafts at a depth of 16m.

○ Diversion of the 1220mm sewer and 9" water main at Albert Road, along/parallel to the north side of the proposed line: open cut, to a depth of 5m.

The impact of the tunnel shafts and open cut trench diversions would be to remove completely potential archaeological remains. The tunnel itself would have no impact.

• Diversion/protection of other services. Details of these will not be available within the timescale of the EIA, but they are likely to partially or completely remove archaeological remains.

• A construction compound, the North Woolwich Worksite, runs along the railway, Albert Road and Factory Road with one area east of Store Road and another west of Henley Road. The 1869 Ordnance Survey map shows the area partly as open ground, industrial buildings (stores) and residential buildings. The area of worksite located in an industrial estate on the west side of Henley Road would necessitate the demolition of existing buildings.


53

• Impacts at both work sites would result from general ground reduction (c 0.5m deep) and the footings for compound accommodation (c 0.4m to 0.8m deep), and at the Henley Road worksite from the footings of Bentonite plant (c 0.5m to 0.9m deep). These works have potential to partially remove potential archaeological remains.

• Changes in groundwater level have been predicted at this site. The potential impact, if any, cannot be adequately quantified due to a lack of detailed information; in particular on present groundwater regime and on the nature of any surviving archaeological remains. However, there are no known resources on the site of a type which might be adversely affected, although there is potential for waterlogged organic remains.

• Removal of the existing North London Line track would probably have no or minimal archaeological impact, confined to the possibility of historic railway infrastructure being encountered.




Survey and geotechnical information, particularly on the depth of the alluvial deposits, in order to refine the mitigation strategy.


The generic data gathering and mitigation measures, as described in the incorporated mitigation, would be applied to this Crossrail site. Initially DDBA and/or field evaluation would be needed to quantify the nature and extent of any archaeological survival (including structural appraisal of any potential industrial archaeology affected by demolitions).


None



Below-ground remains: none required

Possible standing industrial archaeological remains: initial structural appraisal of the historic fabric, in order to determine the appropriate level of recording from those specified by RCHM(E) 1996, to constitute preservation by record


None


Non-Significant


54

Engineering sources




A 500m-radius search of the GLSMR and LAARC,


LB of Newham UDP

Researcher HK, PA, RF,PM, JC

Date 14/01/2005


55

4.5.2 Site 233 Warren Lane Vent Shaft

Site name Warren Lane Vent Shaft Site no. 233


Location Warren Lane, Woolwich, LB of Greenwich

NGR 543540 179250

Proposed Works

Vent Shaft. Temporary use of land immediately to the north and east of the shaft.


The site lies c 100m south of the Thames, located on Head deposits at the base of a slope from higher ground to the south (modern street level c 9m OD). It is possible that alluvium may extend to the site, from interleaving of Head and Alluvial deposits at the southern edge of the Holocene floodplain.

Baseline resources


• The site is located within an Area of Archaeological Potential. • High potential for medieval and later occupation. The site is at the

eastern end of the main historic nucleus of the town, around Church Street, High Street and Market Hill (GLSMR 071466). Warren Lane led to the ferry crossing, which may have medieval origins (see Site 225, above). Other features include field boundaries, land reclamation and drainage ditches (GLSMR 070284, 071080, 071464, 071466); 17th to 19th-century riverside wharves, barge beds, and flood defences; pottery kilns, glass factories and a gas works (Site code RAO98, GLSMR 070305, 070306, 070991, 070993, 070994, 071389, 071469, 071470, 071474, 071475, 223243). The 1869 Ordnance Survey map shows a primarily residential area, lying between the dockyards to the west and Woolwich Arsenal to the east. However, just to the south, along Rope Yard Rails, there was a Tudor rope works (for the ship yards).

• Moderate potential for palaeo-environmental evidence of prehistoric and later date, preserved within the Head deposits or alluvium.


56

• Moderate potential for Iron Age and Roman occupation. The Crossrail site probably lies within, or immediately south of, a possible Iron Age oppidum (fortified proto-town), which also contains evidence of Roman settlement. The site was partly investigated in 1983, 1986 and 1987 by Woolwich District Archaeological Society. The excavations, which are as yet unpublished, revealed a massive 25 ft-wide defensive ditch running north to south down towards the Thames, flanked on the east side by a smaller ditch, and traced for a length of 30m. There were also traces of occupation in the form of ‘a few pits and postholes’ to the west of the ditch. The SMR entry mentions that round houses were found (GLSMR 070992). Pottery and coins suggest that the site originated in the late Iron Age with further activity in the late Roman period. The location of the site on a distinct spur of ground overlooking the river, and the likely role of the river as a tribal boundary, reinforces the interpretation of the site as an oppidum. A Roman cemetery has been recorded to the east, along with finds of votive pottery (see Site 411, below - GLSMR 070260).

• Low potential for Palaeolithic remains sealed beneath or within Head deposits.


The site is currently open land to the north of Warren Lane and is in use as riverside park/civic amenity at street level; dropping towards the river frontage.

Visited ?

Yes

Past impacts Later residential and industrial buildings from Woolwich have probably truncated earlier deposits above the Head, but may themselves be archaeological resources. Note that the proposed Crossrail site lies immediately west of (outside) the former Woolwich power station and therefore potential archaeological remains will not have been affected by the extensive groundworks for its construction in the 1920s.


• High importance: low potential for in situ Palaeolithic remains Reasons: national and local rarity of in situ Palaeolithic evidence; Head is a deposit type likely to preserve such remains.

• Moderate importance: moderate potential for Iron Age and Roman occupation. Reasons: formal designation; local rarity of direct settlement evidence in particular of a possible oppidum; group value with known cemetery; contribution to published priorities (eg Museum of London 2002: 38, 85).

• Moderate importance: moderate potential for palaeo-environmental evidence. Reasons: local rarity of in situ evidence; Head is a deposit type likely to preserve palaeo-environmental evidence; contribution to published priorities (eg Museum of London 2002 19, 79).


57

• Moderate importance: high potential for medieval and later town of Woolwich. Reasons: formal identification within an Area of Archaeological Potential; key feature of local history and landscape; historical supporting data and historical association; diversity and group value of multi-phase urban resources; contribution to published priorities (eg Museum of London 2002, 81).

Impact Ventilation and emergency escape/access shaft. Construction compound (worksite). In detail the impacts are:

• A basement box to house the shaft and associated plant, c 27m by c 24m by c 7m deep, the perimeter retaining walls formed from secant piles. The impact would be to completely remove all potential archaeological remains, with the possible exception of any Palaeolithic remains in the deeper Head deposits.

• A shaft of c13.5m internal diameter, descending to 48m below ground level. The additional impact, within the shaft footprint, would be to completely remove any potential Palaeolithic remains that had survived construction of the basement.

• A construction compound (Warren Lane Worksite) around the basement. Impact: temporary services (0.2m to 1.2m deep); footings for compound accommodation (c 0.4m to 0.8m deep) and grout plant (c 0.5m to 1.0m deep) and ground disturbance for dewatering system (c1.0m deep) may partially remove potential archaeological remains, locally.

• diversion/protection of services. Although details are not yet available, these are likely to partially remove potential archaeological remains.


Moderate, with potential for a Significant impact.


Geotechnical/geoarchaeological and survey data, in particular the levels of Head deposits, in order to refine the mitigation strategy.


The generic data gathering and mitigation measures, as described in the incorporated mitigation, would be applied to this Crossrail site. Initially, DDBA and/or field evaluation would be required in order to refine the mitigation strategy.

This may to lead to archaeological excavation, constituting preservation-by-record.

Residual Impact after incorporated mitigation

None.

The incorporated mitigation measures would constitute preservation-by-record.


58


None required

Residual Impact after site specific mitigation

None.


Non-significant

Engineering sources




A 300m radius search of the GLSMR and LAARC.


Mayhew H and Binny J 1862, The Criminal Prisons of London

WDAS, 1988 ‘Archaeology in Woolwich’ in Proceedings of the Woolwich and District Antiquarian Society, XXXIX

Researcher HK, PA, RF, PM, JC

Date 17/01/2005


59


4.6.1 Site 411 Arsenal Way Shaft

Site name Arsenal Way Shaft Site no. 411


Location Beresford Street/Plumstead Road, Woolwich, LB of Greenwich

NGR 544110 178940

Proposed Works

Ventilation and emergency escape/access shaft and a construction compound (‘worksite’).


On Head deposits, c 100m south-west of the boundary with river alluvium. Ground level is c 8m OD. It is possible that alluvium may extend to the site, from interleaving of Head and Alluvial deposits at the boundary.

Baseline resources


• The site is located in an Area of Archaeological Potential.

• Burial grounds: from c 1776 to 1856, large numbers of convicts dying on the prison hulks moored on the river were buried within Woolwich Warren (cf Mayhew and Binny 1862). Although visible as rows of hillocks, the informal burial grounds were unmarked, with no defined boundaries. They are likely to have been on what was then undeveloped waste ground and marsh to the north-east of Wellington Avenue and the Crossrail site (see Woolwich Arsenal below). Great quantities of human bone were apparently found in this area during construction of the Royal Gun Factories in 1859, with further skeletons unearthed at the Butts in 1912. The ad hoc nature of the burial grounds gives a low potential for human remains within Woolwich Arsenal generally. There is also a potential for Roman burials (see Roman cemetery below).

• High potential for Woolwich Arsenal. Tower Place, a substantial Tudor mansion was fortified by Prince Rupert against the Dutch c 1667 and became an ordnance depot (the Royal Laboratory) c 1695. This area, the original nucleus of the Arsenal (known as Woolwich Warren) includes the Crossrail site and extended north approximately to Wellington Avenue. The discontinuity of layout beyond this point reflects later expansion onto land reclaimed from the Thames marshes. Although the Crossrail site is largely open ground, it was formerly occupied by a variety of buildings from the Arsenal. (Site codes RYA99 and WMS96 and GLSMR 071010, 223243, 071422, 071458, 071459, 070284, 071468, 071477, 071478, 071480, 071784).


60

• Moderate potential for a Roman cemetery found at the Arsenal in the 19th century and confirmed by later fieldwork (Site RYA99, GLSMR 070218, 070228, 070225, 071062). It has been suggested (Brown 2002, 294–5) that Plumstead Road, immediately to the south of the Crossrail site, follows the line of a subsidiary Roman road off Watling Street (A2). The road may have linked a number of Roman settlements along the south side of the River, including a possible ferry crossing at Erith and settlement at Plumstead (to the east), Woolwich itself, and at Charlton, Greenwich, and Deptford (to the west).

• Low potential for in-situ Palaeolithic remains sealed beneath or within Head deposits. Also in the study area, but outside the Crossrail site, for later prehistoric evidence on higher ground overlooking the floodplain, eg possible late Iron Age settlement (GLSMR 070992). Occasional fragments of pottery have been recovered from the vicinity (GLSMR 070566, 070260).

• Low potential for Roman and later occupation and land management, including possible flood defences (Site RYA99 and GLSMR 071392, 071393, 071394).


The site is currently open, street-level hard-standing alongside Beresford Street with a warehouse (currently under conversion) occupying the north-eastern corner.

Visited ?

Yes

Past impacts Later industrial buildings from the Arsenal have probably truncated earlier remains above the Head deposits, but are themselves to be regarded as heritage resources.


• High importance: low potential for in situ Palaeolithic evidence Reasons: national and local rarity.

• Moderate importance: high potential for Woolwich Arsenal, including low potential for convict burials. Reasons: statutory protection for burials; formal identification within Area of Archaeological Potential; supporting historical data and association; diversity and group value of multi-phase resources; potentially good survival quality in an area that has not been recently redeveloped; contribution to published priorities (eg Museum of London 2002: 71, 74, 82, 83, 85).

• Moderate importance: moderate potential for Roman burials, and low potential for Roman and later occupation and land management. Reasons: statutory protection for human remains; formal identification; local rarity of other in-situ remains archaeological supporting data from previous burial finds; contribution to published priorities (eg Museum of London 2002, 85).

Impact Ventilation and emergency escape/access shaft, with associated construction compound (worksite). In detail the impacts are:


61

• A basement box, c 25m by 40m and c 6m deep, to house the shaft and associated plant, the perimeter retaining walls formed from secant piles. The impact would be to completely remove all surviving archaeological remains, with the possible exception of any Palaeolithic remains in the deeper Head deposits.

• A shaft below the basement (to tunnel level): 16m in diameter and 34m deep. The additional impact of the shaft would be to remove any Palaeolithic remains within its footprint which had survived construction of the basement.

• A construction compound, the Arsenal Way Worksite, would be established around the basement. There would be footings for temporary accommodation (0.4m to 0.8m deep); hard standing; temporary services (0.2m to 1.2m); grout plant (0.5m to 0.9m); hoarding posts (0.8m to 1.5m), dewatering systems (1.0m), and a temporary pedestrian overbridge (up to 1.0m). Impact: these works could partially remove any remains surviving close to the modern ground surface (eg from Woolwich Arsenal).

• Details of service diversions are unlikely to be available within the timescale of the EIA, but they are likely to partially remove potential archaeological remains.


Moderate, with potential for a Significant impact.


Geotechnical/geoarchaeological and survey data, in particular levels of Head deposits, in order to refine the mitigation strategy. Documentary evidence regarding the 18th/19th-century buildings of the Arsenal.



Initially, DDBA and/or field evaluation would be required in order to refine the mitigation strategy. This may to lead to archaeological excavation, constituting preservation by record.


None:



None required


None


Non-significant


62

Engineering sources




A 300m radius search of the GLSMR and LAARC.


Brown G, 2002 ‘Roman Greenwich’ in Archaeologia Cantiana, CXXII 2002

Mayhew H and Binny J 1862, The Criminal Prisons of London


Date 17/01/2005


63

4.6.2 Site 295 Plumstead Road (near): ground settlement between search areas 411 & 227

Site name Plumstead Road (near): ground settlement between search areas 411 & 227

Site no. 295


Location Maxey Road to Villas Road, Woolwich, LB of Greenwich

NGR 544360 178890

Proposed Works

Tunnels only (1–25mm settlement predicted)


The route crosses higher ground (typically c 11m OD) comprising Head deposits over Thanet sandstone, overlooking the lower Thames marshes and alluvium to the north.

Baseline resources

• No Scheduled Ancient Monuments within search area

• The site is not located within an Area of Archaeological Potential.

• High potential for 17th to 19th-century brick making industry eg clay pits and brick fields (GLSMR 071784 and 071785). Substantial brick fields are shown to the south of the existing railway on the 1866 Ordnance Survey map.

• Low potential for Palaeolithic remains sealed beneath or within Head deposits. Also for later prehistoric evidence: occasional fragments of pottery have been recovered from the surrounding area, but outside the search radius (GLSMR 070566, 070260).

• Low potential for Roman and later occupation, the focus of which is to the west, outside the search area (Site RYA99 and GLSMR 071392, 071393, 071394).


Mostly built-up, with open ground, around Maynards House and Greenwich Community College.

Visited ?

No

Past impacts Existing buildings and post-medieval clay pits will have had some level if impact on earlier deposits.


• High importance: low potential for Palaeolithic remains Reasons: national and local rarity of in situ Palaeolithic evidence; a deposit type; likely to preserve such remains.

• Low importance: high potential for 17th to 19th-century clay pits and brick fields. Reasons: limited contribution to published priorities.

• Low importance: low potential for later prehistoric, Roman and later occupation. Reasons: previous finds suggest fragmented evidence with limited contribution to published priorities.


64

Impact There are no known structural archaeological remains between search areas 411 and 227 which might be affected by this minor ground settlement.


None

Mitigation N/A


N/A

Residual Impact

None

Magnitude of Residual Impact

None


Non-Significant

Engineering sources


Sources


A 300m-radius search of the GLMSR, LAARC


Researcher HK, PA, JMCB, JC

Date 21/12/04


65


4.7.1 Site 227 Plumstead Portal

Site name Plumstead Portal Site no. 227


Location Plumstead High Street bridge to c 250m east of White Hart Road bridge, LB of Greenwich.

NGR 545240 178860

Proposed Works

Tunnel portal consisting of an extensive cut-and-cover approach ramp, with retaining walls; new bridge; realignment of North Kent Line (NKL) and construction compounds (worksites). A number of services/utilities would require diversion/protection.


To the east from Plumstead High Street, the route leaves the edge of Head deposits on higher ground at c 5m OD, and crosses alluvium of the former Thames marshes, where street level falls to c 2m OD.

Baseline resources

• No Scheduled Ancient Monuments within the search area, although a possible prehistoric burial mound on Winn’s Common, Plumstead overlooks the site from the ridge c 1km to the south (Scheduled Ancient Monument LO 132).

• The search radius includes an Area of Archaeological Potential, but this does not extend to the Crossrail site, which lies 160m to the north.

• Moderate potential for Mesolithic and later prehistoric activity at the edge of the higher ground and alluvial floodplain for example, for Bronze Age timber trackways (c 9 examples along Thames and tributaries, nearest are HE-ED93, 3.8km to the north-west, and BAW95, 5.5km to the east). Also high potential for associated palaeo-environmental evidence, preserved within the alluvium or Head deposits.

• High potential for post-medieval activity, particularly gravel and brick quarry pits (GLSMR 800010, 071728, 071785, 071786, 071787, 071788).

• Moderate potential for medieval land management. The late Saxon and medieval village of Plumstead lay along the High Street, focused around the church and manor house, at the junction with Church Manor Way to the south of the Crossrail route (GLSMR 070291, 223570). However, as late as 1888, the Ordnance Survey shows the existing railway passing through undeveloped open land between the village and Plumstead marshes to the north. The potential is mainly for land reclamation and agricultural features, such as drainage ditches, embankments and field systems.


66

• Low potential for Palaeolithic remains sealed beneath or within Head deposits.

• Low potential for Roman and later occupation (GLSMR 070214, 070256, 070278, 070280, 070313, 070314, 070319, 070322, 070387).


Railway land: the tracks emerge from a cutting at Plumstead station and, moving east onto lower ground, they are set on an embankment and viaduct. The site includes the sidings of Plumstead Goods Depot, to the north.

Visited ?

Yes

Past impacts Partly truncated by railway cutting and existing tracks.


• High importance: low potential for in situ Palaeolithic remains. Reasons: national and local rarity of in situ Palaeolithic evidence; a deposit type likely to preserve such remains.

• Moderate importance: high potential for Mesolithic and later prehistoric activity, and for associated palaeo-environmental evidence. Reasons: local rarity of in situ remains; two deposit types likely to preserve palaeo-environmental evidence and organic artefacts; topography conducive to past settlement, contribution to published priorities (eg Museum of London 2002 19, 79).

• Moderate importance: moderate potential for medieval and later land management and use. Reasons: local rarity of in situ remains; historical supporting data; contribution to published priorities (eg Museum of London, 2002, 59, 74, 79, 81, 82, 83, 88).

• Low importance: low potential for Roman and later occupation. Reasons: likely to be fragmented evidence, primarily isolated artefacts with limited contribution to published priorities.

• Low importance: high potential for post-medieval quarry pits. Reasons: limited contribution to published priorities.

Impact The proposed portal works consist principally of the tunnel eye and shaft, approached by an extensive length of cut-and-cover tunnel approach ramp. The eye shaft would be used for construction of the running tunnels and on completion would become an intervention and evacuation point. There would also be two construction compounds (worksites) linked by a new access road. A new overbridge would be constructed to take White Hart Road and service diversions are planned. Moving eastwards, the impacts are:

• Tunnel eye and shaft c 21m by 30m (internal) with perimeter diaphragm walls descending to c –23.5m OD. The impact would be to completely remove all surviving archaeological remains.

• 670m-long tunnel approach ramp of six sections, ascending from c –12m OD to ground level and thence to NKL (embankment) level (c 4m OD). The impact of its construction would be to completely remove all surviving archaeological remains (excluding the final section of graded ballast from ground to embankment level).


67

○ 78m-long cut-and-cover tunnel, with diaphragm walls, ascending from c –11.7m OD to –9m OD.

○ 219m-long propped retained cut (including new White Hart Road overbridge) with diaphragm walls.

○ 141m-long cut-and-cover tunnel, with diaphragm walls. ○ 131m-long retained cut with diaphragm walls. ○ 35m-long retained cut with temporary sheet piles and

permanent concrete U-section ground support. The excavated depth for this section would vary from 4m to 1m.

○ 66m-long graded ballast to bring the Crossrail track up from ground level to run onto the old NKL alignment.

• Earth embankments for NKL track realignments are required east of the tunnel approach ramp. They are not piled but reinforced where necessary with textile. The impact of the construction of these embankments would probably be to partially remove any surviving archaeological remains through topsoil stripping, but details of the works required will not be available within the timescale of the EIA.

• Piled retaining walls are required where it is impossible to use earth embankments. The impact would be to completely remove any surviving archaeological remains along the line of contiguous piling for the walls.

• Noise barriers are required from the Plumstead Portal as far east as Abbey Wood Station. No or minimal impact due to the shallow depth of foundations (c 0.5m).

• Two construction compounds:

○ the Plumstead Worksite along the railway and on open ground north of the NKL and in the former Plumstead Goods Depot. The depot is on land raised c 1.5 to 2m above the surrounding ground levels, and therefore these works would have no impact.

○ the Plumstead Worksite West located on the south side of Nathan Way to be used for spoil handling would include footings for a conveyor (c 0.5m to 0.9m deep). The impact of this would be to partially remove any potential archaeological remains within their individual footprints.

• Temporary changes in groundwater level have been predicted at this site. The potential impact, if any, cannot be adequately quantified due to a lack of detailed information; in particular on present groundwater regime and on the nature of any surviving archaeological remains. However, there are no known resources on the site of a type which might be adversely affected, although there is potential for waterlogged organic remains.


68

• Major service diversion: Electricity cables at White Hart Road would be diverted through cut-and-cover trenches at 1.5m depth and pipejacked through the existing railway embankment. Although details will not be available within the timescale of the EIA, it is likely that there would be no impact, as the works are predicted to take place within modern artificially raised ground on both sides of the line (including the railway embankment).




Survey and geotechnical information on the depth of the alluvial deposits, plus technical details (eg on service diversions) in order to refine the mitigation strategy.

Incorporated Mitigation


Residual impact after incorporated Mitigation



None Required


None


Non-Significant

Engineering sources




A 750m radius search of GLSMR and LAARC.



Date 17/01/2005


69

4.8 Route Window SE6A

4.8.1 Site 413 Manor Wharf

Site name Manor Wharf Site no. 413

Route Section South-East Window SE6A

Location Land north of Norman Road, LB of Bexley. In the reclaimed marshland on the southern side of the River Thames at Halfway Reach. North of Belvedere and immediately east of Crossness Sewage Works.

NGR 549545 180685

Proposed Works

Restoration of existing jetty, with conveyors connecting jetty to one, possibly two, stockpile areas. Haul road. Dredging of channel.


Most of the site is located in the Erith Marshes, on land that was drained and reclaimed in the medieval period. The northern part of the site falls within River Thames foreshore and channel. Historic maps show a large inlet immediately to the west of the site, which originally formed the mouth of a large creek prior to reclamation.

The site lies on alluvium above London Clay. That part of the site on dry land is covered with modern ‘made ground’ of unknown depth (British Geological Survey), although it was noted on the site visit that the level of the surviving marshland to the south is only slightly (c 0.5m) lower, suggesting that the made ground is not deep.

Baseline resources

• The site and 1km search area around it contain no Scheduled Ancient Monuments.

• The entire site falls within a LB of Bexley Archaeological Priority Area.

• The Crossness Sewage Works immediately west of (outside) the Crossrail site dates to 1862–5, although the modern treatment plant dates to 1963 (Cherry and Pevsner 1983). It was one of two such works built by Sir Joseph Bazalgette to solve London’s sanitation problem, the other being located on the opposite side of the River at Barking. The Crossness works originally comprised six and a half acres of brick-roofed interception/storage tanks and an engine house. The latter is a Grade I listed building of Victorian Romanesque style, and contains the four original pumping engines. Untreated sewage was discharged directly into the Thames, which resulted in large mudbanks of sewage forming downriver from the outfall (possibly including the channel and foreshore areas of the Crossrail site). As a result, from 1887, covered sedimentation channels were introduced to separate the liquid effluent from the solid sludge, with only the former being discharged into the river. Up until 1998, a fleet of special boats was used to transport the solid sludge for disposal at sea.


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• High potential for prehistoric and later palaeo-environmental evidence within the alluvial sequence on dry land and on the Thames foreshore, where there is a potential for exposed former land surfaces, which, further inland, would otherwise be buried beneath substantial depths of alluvium. This includes a potential for good organic preservation and information on the changing river regime (site codes: NMN97 c 325m to the west, just outside the Route Window; and PCD98 and EWY01, c 300m and c 800m to the south). Important and extensive outcrops of preserved prehistoric forest are exposed at low tide on both banks of the River along this section of the Thames foreshore, in particular at the edge of Erith Marshes c 2.4km to the south-east, where mainly prehistoric yew trees have been identified since the late 19th century, and at Rainham, on the opposite site of the river, where trees and possible reed beds have been recorded. Probable prehistoric antler fragments, shells, nuts and wood fragments have been recorded at a depth of 28–31ft in the area of Belvedere Power Station, c 450m to the east of the Crossrail site (GLSMR 070535).

• High potential for medieval and early post-medieval flood management (possibly earlier), land reclamation and economic activity within the former marsh. This potential includes possible wharfs and hulked vessels along former creeks, seasonal embankments used to protect summer crops, sheep shelters, and secondary permanent and seasonal settlement on higher ground or artificially raised areas in the marsh. In 1230 and 1240, the abbot and convent of Lesnes Abbey (c 2.4km to the south-west of the Crossrail site) constructed sea walls in the Plumstead marshes, and by the end of the 13th century had reclaimed, much to their benefit, their land in the marsh (Hasted 1797, 217–9). It is likely that the adjacent Erith Marshes, within which the Crossrail site lies, were reclaimed at the same time, also probably in stages. The marshland was crossed by a network of drainage ditches enclosing individual parcels of land and would have been very important economically for activities such as animal husbandry, arable cultivation, and possibly pottery/brick manufacture. Flooding was common, and on a number of occasions laid the marsh pasture to waste, eventually being considered important enough to require almost yearly sewer commissions responsible for inspection and maintenance of the walls. Historic maps consulted from 1769 show a sea wall within the Crossrail site: this is likely to form part of the existing modern sea defences. Norman Road (originally Picardy Manorway after the manor house of Picardy c 1.5km to the south) terminates immediately to the south of the Crossrail site. The road was a typical medieval ‘manor way’, a raised trackway that provided access across the marshes from the settlement on the higher ground, and which probably also served as a flood defence and possibly as a land division.


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• High potential for post-medieval industry. Andrews, Drury, and Herbert’s map of 1769 shows ‘Powder House’ on the side of the small inlet immediately west of the Crossrail site. The more detailed (and probably more accurate) Ordnance Survey Drawing of 1799 shows this as the ‘Erith Magazine’ immediately to the west, and possibly within the western edge of, the Crossrail site. The magazine was one of two in the marshes between Erith and Woolwich, the other being Plumstead Magazine to the west. In 1864, the Erith Magazine, owned by John Hall and holding 750 barrels of gunpowder, exploded with such force that the noise was heard within 40 miles. The river wall was breached and barges destroyed. Two thousand troops and navvies worked day and night to rebuild the embankment and save a large area of low-lying ground from being flooded. The Ordnance Survey map of 1870–75 does not show the magazine, but shows a ‘Manure Works’ within the Crossrail site, comprised of a large L-shaped building beside the River wall, with outbuildings to the west, south and east, and two piers to the north. The buildings are no longer extant, although footings may survive below ground. If the Erith Magazine was the site of the explosion, it is likely that this removed all structural remains of the building.

• Moderate potential for prehistoric activity in the former marshes, in particular beside former channels and on eyots (natural islands), and on the Thames foreshore, where there is a potential for exposed former land surfaces (see above). From the late Mesolithic/early Neolithic, the intertidal wetland environment would have been important in providing predictable resources such as food (hunting and fishing), reeds, salt from evaporation, clay for pottery manufacture, along with rough grazing. A late Mesolithic/early Neolithic flint tool was discovered in alluvial silts c 925m to the south (NOM97). In 1885, a prehistoric log boat containing a polished flint axe and a scraper was found in the marsh peat c 1km to the south-east of the Crossrail site (GLSMR 070415). In 1995–6, archaeological investigations c 675m to the south (site code: BAW95) revealed evidence of extensive late Mesolithic flint tool manufacture, along with numerous worked wood objects, and a section of a hurdle-built trackway of Bronze Age date. A wooden structure of prehistoric date was also recently recorded at the eastern end of the Thamesmead/Erith Spine Road, c 2.4m to the west of the Crossrail site. Bronze Age (and later) timber structures and/or trackways would have provided access across boggy areas, and well-preserved examples have been found at a number of other locations on both sides of this stretch of the River.

• Moderate potential for Roman activity in the former marshes prior to reclamation in the medieval period (possibly earlier), in particular beside former channels and on eyots, and on the Thames foreshore, where there is a potential for exposed former land surfaces (see above). As with the late prehistoric, the intertidal wetland environment would have been exploited for a range of resources


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(see above). In the late 19th century, Spurrell, a local enthusiast, noted unspecified Roman remains on the intertidal zone bordering the Crossrail site (GLSMR LO8437). Other evidence of Roman activity comprises hearths, pottery, quernstone fragments and building tiles, found c 1.5km to the north-west of the Crossrail site. In c 1865, pottery, mortar, tiles, wood, animal and human bone, and a cinerary urn were found 9ft below the surface, c 1km to the west. Roman settlement has also been found at Erith along the higher ground to the south of the marsh, and close to the existing foreshore of the Rainham marshes on the opposite side of the River, the latter possibly linked with a ferry.

• High potential for wrecks and riverfront structures in the intertidal and subtidal areas. The UK Hydrographic Office records a ‘live’ (presence confirmed) unclassified obstruction in the intertidal zone bordering the Crossrail site (UKHO 13389). The date and nature of this obstruction is not currently known, but it is potentially of archaeological interest. The Kent SMR records four shipping losses (Kent SMR KE12368; KE12371; KE12744; KE12745) along this stretch of the River (exact location is not known), two of which are of 18th-century date. The Ordnance Survey 1st edition map of 1870–75 shows two piers extending from the northern edge of the site. No remains of these were noted on the site visit.


The site was until recently a car park and jetty owned by the Ford Motor Works Company, serving the plant at Dagenham (est. 1931) on the opposite side of the River. The site is currently open ground, almost entirely surfaced with old tarmac, concrete hardstanding and low concrete slab foundations of several non-extant buildings, and is slightly higher (c 0.5m) than the level of surviving marshland to the south. The western part of the site has a large disused hangar of steel girders on concrete bases with a corrugated roof, along with and a small disused modern brick building to the east of it.

The sea wall comprises a c 5m high earth embankment with a c 1m high concrete wall on its seaward side. Within the site, the western section of embankment has a lower embankment abutting its southern side, possibly representing the remains of an earlier and less substantial sea wall. In the central section, this lower embankment has been removed for the construction of several buildings (non-extant other than the northern walls) abutting the larger embankment. There are four disused timber jetties along the stretch of foreshore to the north of the site (not accessed), with a disused high conveyor/piperack connecting the foreshore to the larger, eastern, jetty (to be restored). The foreshore south of the large jetty is enclosed by a low wall, which contains silt and modern debris (metalwork, bricks). No exposed outcrops of peat or trees were noted in the foreshore area.

Visited ?

Yes (14/12/04)


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Past impacts A major explosion in 1864 is likely to have caused damage to potential archaeological remains at the very top of the alluvial sequence in the area immediately west of, and possibly within the western edge of, the Crossrail site (ie medieval/post-medieval remains. Earlier, more deeply buried, remains probably survived intact). It also destroyed a section of the sea wall, and this possibly included a section within the western part of the Crossrail site.

Construction of previous buildings on the site, such as the 19th-century Manure Works, may have resulted in the truncation of potential archaeological remains at the top of the alluvial sequence, but will have left the more deeply buried (ie earlier) remains in tact.

Former land use, in the form of a gunpowder magazine and manure works, along with material issued into the channel from the adjacent Crossness sewage works, is likely to have resulted in some ground contamination in the dry and intertidal areas.


• High Importance: low potential for prehistoric timber trackways and hulked vessels. Reasons: potential to contribute to published priorities including the research question “Understanding the relationship between the wooden trackways in the floodplain…” (Museum of London, 2002, 25); local and regional rarity of such finds to date, supporting data from other excavated trackways; good survival quality of organic remains within alluvium; and the vulnerability of the wooden structures.

• Moderate importance: high potential for palaeo-environmental data contributing to reconstruction of Late Glacial and Holocene landscape change, and changing sea levels. Reasons: formal designation within an Archaeological Priority Area; potential to contribute to the local published priorities (eg Museum of London 2002, 79 & 80).

• Moderate importance: moderate potential for prehistoric activity in the former marshes, including the foreshore area. Reasons: formal designation within an Archaeological Priority Area, supporting data from other nearby sites; and the contribution to published priorities (eg Museum of London 2002). In the alluvium: survival quality of organic materials within a deposit type likely to preserve associated evidence of past land use.

• Moderate importance: moderate potential for Roman activity in the former marshes, including the foreshore area. Reasons: formal designation within an Archaeological Priority Area, supporting data from other nearby sites; and the contribution to published priorities (eg Museum of London 2002). In the alluvium: survival quality of organic materials within a deposit type likely to preserve associated evidence of past land use.


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• Moderate importance: high potential for medieval and early post-medieval (and possibly Roman) flood management, land reclamation and economic activity within the former marsh. Reasons: formal designation within an Archaeological Priority Area, supporting data from other nearby sites; and the contribution to published priorities (eg Museum of London 2002).

• Moderate importance: high potential for post-medieval industry Reasons: formal designation within an Archaeological Priority Area, potential to contribute to the local published priorities (including Museum of London 2002, 69, 74), historical and archaeological supporting data.

Impact Restoration of existing jetty, dredging of channel, conveyors, ground disturbance associated with to one, possibly two, stockpile areas and haul road.

• Jetty restoration. Details of the restoration of the jetty will not be available within the timescale of the EIA, although new piling would not be required and consequently there is likely to be no impact.

• Dredging of channel. Details of the dredging will not be available within the timescale of the EIA, although its impact would be to remove partially or completely potential archaeological and palaeo-environmental remains contained within the channel silts.

• Conveyor. It is assumed that the conveyor footings would require excavation of up to 0.9m below ground level. If this extends beneath the existing modern made ground (of uncertain nature and depth), the impact would be to remove partially potential archaeological remains. This would affect remains at the top of the alluvial sequence but would leave earlier, more deeply buried, remains (ie prehistoric and Roman) intact.

• Stockpile areas and haul road. Although its exact extent and depth is not currently known, the assumed initial ground reduction of 0.5m within these areas is unlikely to be of sufficient depth to penetrate the underlying alluvium, consequently there would be minimal or no impact upon potential archaeological remains.


Low (depending on the extent of dredging), with potential for a Significant Impact


In order to refine the mitigation strategy, further geotechnical and survey data on the existing levels of truncation and survival.


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Initially, DDBA and/or field evaluation would be required to establish levels of survival. This would include a foreshore survey in order to identify the presence, nature and significance of any remains of archaeological interest in the foreshore zone, in those areas to be affected. This is likely to lead (where impacts have been identified) to archaeological excavation, constituting preservation by record.


None The incorporated mitigation measures would constitute preservation by record. In a consultation meeting on 28.7.04, EH and GLAAS agreed that preservation by record was suitable for prehistoric timber trackways.


None required


None


Non-Significant

Engineering sources



Sources


A 1km search of GLSMR, Kent SMR (channel), LAARC and for SAMs around the Crossrail site.

A 1km search of the United Kingdom Hydrographic Office (UKHO) wrecks database around the Crossrail site.


Cherry B and Pevsner N, 1983 The Buildings of England. London 2: South

Dartford Town Archive website (www.dartfordarchive.org.uk)

Hasted 1797, The History and Topographical Survey of the County of Kent, p 217

Andrews, Drury and Herbert’s Map, 1769

Ordnance Survey Drawing 3” to 1 mile, 1799

Ordnance Survey 1”map, 1844

Ordnance Survey 1st edition 6”map, 1870–5

Researcher JC Date 21/12/04


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4.9 Route Window SE7 and SE8

4.9.1 Site 400 Abbey Wood Station and Plumstead to Abbey Wood 4-Tracking

Site name Abbey Wood Station and Plumstead to Abbey Wood 4-Tracking

Site no. 400

Route Section South-East Windows SE7–8

Location Abbey Wood, LBs of Greenwich and Bexley

NGR 547330 179040

Proposed Works

Abbey Wood Station (RW SE8): Includes extension of existing platforms, surface works, replacement of existing overbridge and service diversions.

Plumstead to Abbey Wood 4-Tracking (RW SE7–8): The existing railway corridor to be widened to 4 tracks from Church Manorway (RW SE7) to Northwood Manor Primary School (RW SE8). Includes works on three bridges, reversing sidings, two new platforms as central walkways for servicing, and service diversions.


Near the edge of the Thames floodplain, on the alluvium of the former Erith and Plumstead marshes, the underlying Upper Chalk being exposed on the higher ground c 100m to the south. Abbey Wood station lies immediately west of the Great Breach Dyke, which flows from Shooters Hill to the south-west into the Thames to the north. There is also another unnamed river/watercourse that flows east–west just 60m north of the site. The existing railway runs along an artificial embankment, which decreases in height eastwards (c 0.2m high at Abbey Wood station).

Baseline resources

• The Crossrail site lies 590m north-west of the Augustinian Lesnes Abbey, founded in 1178, and a Scheduled Ancient Monument (LO 103, GLSMR 212000). The Crossrail works would not physically affect this monument. Note: the southern extent of the monument, as exposed by archaeological work from the 1950s onwards (in particular the church), is not covered by the English Heritage mapping of the scheduled area, which pre-dates this fieldwork, and has been used as the basis for the figures which accompany the Environmental Statement and this technical report. The discrepancy is not relevant to the Crossrail scheme.

• The Crossrail site lies 400m north-west of an Area of Archaeological Potential, which includes Lesnes Abbey.

• High potential for Mesolithic and later prehistoric evidence, including palaeo-environmental sequences (as per Site 227, above). Nearest timber trackway is BAW95, 3.2km to the east. A few flint artefacts in the study area may suggest associated activity (GLSMR 070552, 070562).


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• Moderate potential for medieval and later land management. The Crossrail site lies outside the precinct of Lesnes Abbey, on the edge of the marshes to the north, parts of which were reclaimed by the Abbey in the medieval period (see Site 413). The 1805 survey shows a small group of houses at the junction of Abbey Road and Manor Way, but the focus of settlement was on higher ground to the south. The site vicinity is still shown as undeveloped marginal land on the 1888 Ordnance Survey map. The potential is mainly for land reclamation and agricultural features, such as drainage ditches, flood embankments and field systems.


The area around the Crossrail Site is fairly level. The ridge to the south begins about 100m away and only rises gradually. The station platforms are about 1.5m higher than external ground level to the south and possibly slightly elevated to the north. There is intensive building activity to the north-west.

Visited ?

Yes

Past impacts Construction of railway, 1849.


• Moderate importance: high potential for Mesolithic and later prehistoric remains, including palaeo-environmental sequences. Reasons: as per Site 227, above. Timber structures such as trackways etc would be of high importance.

• Moderate importance: moderate potential for medieval and later land management. Reasons: as per Site 227, above.

Impact Work would include the demolition of the existing station and public footbridge. The new station would comprise an elevated concourse, at bridge level over the tracks and island platforms. Access to the ground level platform would be via stairs, escalator and a lift at the west end of the platform. Escape bridges would be located at the middle and east end of the platform, and a pedestrian subway at the western end. The laying of two new tracks. Two new footbridges at Church Manorway and Borstal Manorway. Bridges at Eynsham Drive and Harrow Manorway to be strengthened, new reversing sidings and platforms, construction compounds, and service diversions. The impacts are:

Abbey Wood Station (RW SE8)

• New high-level station concourse building with escalator, stairs, new subways and lift to platform supported on concrete walls and piled foundations. The impact of piled foundations and other works would be to completely remove potential archaeological remains within their individual footprints.

• Two island platforms for the Abbey Wood Station eastbound and westbound Crossrail platforms, 245m long, c 5m wide at either end widening in the middle to c 7m. The impact of the construction of the 1.0–1.5m deep footings for the platforms would be to partially remove potential archaeological remains


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• Pedestrian subway. This 2.5m-deep by 2.0m-wide underpass would be located beneath the railway at the western end of platforms, accessed from both platforms and the southern side of the railway via three extensive approach ramps. The underpass would provide temporary access to the station during construction work and permanent emergency access once the work was completed. The impact of construction of the underpass would be to remove partially or completely potential archaeological remains, and partially remove them from the top of the approach ramps where the depth of excavation is progressively less deep.

• Escape bridges for both platforms. The impact of the footings (up to 1m deep) for the bridges would be to partially remove potential archaeological remains, and completely remove them within the footprints of any piles, if required.

• Partial demolition and reconstruction of the road bridge for Harrow Manorway. The impact of the construction of the new piled supports would be to partially remove potential archaeological remains, and completely remove them within the footprints of individual piles.

• Two construction compounds, Harrow Manorway Worksite North and Abbey Wood Station Worksite South are required for Abbey Wood Station. These are to be located in the existing car parks, one to the north, which would include part of Felixstowe Road, and one to the south of the existing station. These would include accommodation offices (c 0.4m to 0.8m deep), temporary services (c 0.2m to 1.2m deep) and at the Harrow Manorway Worksite a tower crane (c 1.5m to 2.0m deep). The impact of these works would be to partially or completely remove potential archaeological remains within their individual footprints.

4-Tracking

• Earth embankments (widening) for new Crossrail track are required at intervals from Church Manorway (RW SE7) to Northwood Manor Primary School (RW SE8). They are not piled but reinforced where necessary with geotextile. The impact of the construction of these embankments, including minor levelling works on the north side of the rail corridor prior to their construction, would be to partially remove any surviving archaeological evidence through the stripping of the ground surface and the removal of trees.

• Piled retaining walls would be required where it is impossible to use earth embankments (not defined whether RW SE7 and/or SE8). The impact of construction of the walls and the underlying piles and their pile caps would be to partially remove potential archaeological remains, and completely remove them within the footprints of individual piles.


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• Noise barriers are required from the Plumstead Portal (RW SE7) as far as Northwood Manor Primary School (RW SE8). The foundations for these 2m-high barriers would be 0.5m deep. The impact of these would be to partially remove potential archaeological remains within their individual footprints.

• Construction of replacement footbridges over Bostall Lane (Bostall Manorway in ES Scheme Description) and Church Manorway (both RW SE7). The impact of the foundations (depth c 1m) would be to partially remove potential archaeological remains.

• Strengthening of the road bridge for Eynsham Drive (RW SE7). The impact of the construction the new piled supports would be to partially remove potential archaeological remains, and completely remove them within the footprints of individual piles.

• Reversing sidings with two 245m long service platforms for Crossrail and a single reversing siding for the North London Line are required to the east of Abbey Wood Station and west of Northwood Primary School (RW SE8). Platform footings would penetrate 1.0m to 1.5m below ground. Trackbeds for sidings would reach up to 1m below ground level, lineside drainage might be deeper. Track levels are mainly at ground level, so cut and fill would be minor. Platform footings, trackbeds and drainage are likely to partially remove potential archaeological remains.

• Eight further construction compounds, are required at various points along the line, six in built-up areas, one on parkland (Eynsham Drive RW SE7), and the Abbey Wood Sidings Worksite along the southern edge of Alsike Road and open land to the east. These sites would include accommodation offices (c 0.4 to 0.8m deep), and temporary services (0.2m to 1.2m deep). The impact of these facilities would be to partially remove potential archaeological remains within their individual footprints.

• Services diversions: The diversion of electricity cables at Church Manorway (RW SE7) would comprise of a 1.5m deep trench, with the cables pipejacked beneath the existing railway embankment. Reconstruction of sewers at Mottisford Road/Bracondale Road (RW SE 7) would require the sewers to be pipejacked at a depth of 3m. A sewer diversion at Abbey Wood station (RW SE8) would comprise a 3.5m deep cut-and-cover trench. The impact of these is likely to partially or completely remove potential archaeological remains.

• Details of the impact of other service diversions will not be available within the timescale of the EIA, but these are likely to partially remove potential archaeological remains.


Moderate with potential for a Significant impact.


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The generic data gathering and mitigation measures, as described in the incorporated mitigation, would be applied to this Crossrail site. Initially DDBA and/or field evaluation would be required to establish levels of survival. This is likely to lead to further archaeological investigation, potentially to the base of the alluvium, constituting preservation by record.

Residual impact after incorporated Mitigation



None required


None


Non-Significant

Engineering sources




A 1km-radius search of the GLSMR and LAARC.


Researcher JMCB, IH, MM, PA, RF, PM, JC

Date 18/01/2005


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5 Appendix 1: Site specific assumptions

Victoria Dock Portal SE2 For the DLR diversion, track laying and

drainage may exceed the generic 0.6m disturbance assumed for track construction. For the temporary site footbridge over the diverted DLR, assume foundations to 1m depth. For the hardstanding required for the emergency assembly area, assume 0.5m excavation.

Arsenal Way Shaft SE5 For the temporary pedestrian overbridge – assume footings to 1m depth

Plumstead Portal SE6 For minor earthwork embankments – assume topsoil stripping and some ground preparation prior to laying of geotextile.

Abbey Wood Station SE8 The footbridges would require footings to 1m depth.

CROSSRAIL ASSESSMENT OF ARCHAEOLOGY IMPACTS, ……IMPACTS, TECHNICAL REPORT. PART 4 OF 6,...

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