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I n t r o d

u c t i on

Victoria EmbankmentForeshore

Thames Tunnel

Currently, untreated sewage regularly overows into the River Thames from London’s Victorian sewerage systemvia combined sewer overows (CSOs). The proposed Thames Tunnel would intercept these overows through theuse of a new storage and transfer tunnel, which would link west London and Abbey Mills Pumping Station. Thesewage ow would then be transferred to Beckton Sewage Treatment Works via the Lee Tunnel. The reduction

in untreated sewage entering the River Thames would bring long-term benets for the environment and users of the River Thames. In order to deliver the project we need a number of sites along the route and this documentidenties our current preferred site at Victoria Embankment Foreshore.

S i t ei nf or m a t i on p a p er

1

Key facts

Local authority: City of Westminster

CSO name: Regent Street CSO spill volume in an average year: 94,000m³ (equivalent to approximately

38 Olympic swimming pools)

Site type: CSO site

Duration of main construction works: Approximately four and a half years.



Victoria Embankment Foreshore

2

Section 1: Introduction and site information

Related documents:

Build

We are proposing to use the foreshore of the River

Thames, south of Victoria Embankment (A3211), forthis construction work and to accommodate permanent

structures required to operate the main tunnel. The site

would be used to control the existing local CSO, known as

the Regent Street CSO, by connecting the northern Low

Level Sewer No.1 to the main tunnel.

These works, along with our works at the Blackfriars

Bridge Foreshore and Chelsea Embankment Foreshore

sites, mean that we do not need additional sitesto intercept the following CSOs along the northern

embankment: Smith Street, Queen Street, Church Street,

Grosvenor Ditch, Kings Scholars Pond, Western Pumping

Station, Northumberland Street, Savoy Street, Norfolk

Street and Essex Street.

The location of the site is shown in Figure 1A. The site is

located in the foreshore of the River Thames, with part of

the site extending west onto the Victoria Embankment(A3211), along which the Thames Path is located. The

Tattershall Castle floating bar and restaurant is located

within the site. The Hispaniola restaurant ship lies

immediately to the north, with the Hungerford rail bridge/

Golden Jubilee footbridges and Embankment Pier beyond.

Embankment Station is located to the north. Beyond

Victoria Embankment (A3211) to the west is Victoria

Embankment Gardens. The site is within the Whitehall

Conservation Area.

This site information paper sets out our proposals at

Victoria Embankment Foreshore. We have also producedproject information papers, which cover overarching

topics relating to the project. Where we consider that a

project information paper is particularly relevant, we have

highlighted this in a related documents box. At the end

of this site information paper is a list of other documents,

which may be of interest and a glossary of terms.



Introduction

3

Figure 1A: Victoria Embankment Foreshore location plan

Victoria

Embankment

Gardens

Golden JubileeFootbridges

C h a r i n g C r o s s

S t a t i o n

S t r a n

d

V i c

t o r i a

E m

b a n

k m e n

t

N o r t h u m b e r l a n d Av e n u e HungerfordBridge

Low LevelSewer No.1

RegentStreet CSO

NorthumberlandStreet CSO

N

CITY OF WESTMINSTER

LAMBETH

Local authorityboundary

Draft limit of land tobe acquired or used

Proposed tunnelroute – centreline

Existing sewer

Existing CSO




4

Related documents:

Q&A Consultation

Site selection

How we chose this site

What we proposed at phase one consultationThrough our site selection process, we identified two

possible shortlisted sites to control the Regent Street

CSO by linking the northern Low Level Sewer No.1 to

the main tunnel. At phase one consultation, which was

held between September 2010 and January 2011, we

presented these sites:

•Victoria Embankment Gardens

•Victoria Embankment Foreshore.

Victoria Embankment Foreshore was identified as our

preferred site at phase one consultation.

What we are proposing at phase two consultation

We have considered the comments from phase one

consultation, feedback from ongoing engagement and

new information; and undertaken further technical work.

We still consider that Victoria Embankment Foreshore

should be our preferred site because the use of the

foreshore is preferable to the temporary loss of and the

potential permanent effects upon the Grade II listed

Victoria Embankment Gardens.



Construction

C on s t r u c t i on

5

Section 2: Construction

Construction activitiesConstruction activities are required to control the CSO

flows by linking the existing northern Low Level Sewer

No.1 to the main tunnel. We would construct an overflow

weir chamber in the Low Level Sewer No.1. A connection

culvert would link the overflow weir chamber to a drop

shaft (approximately 50m deep), from which flows would

pass down to a short connection tunnel. This would then

join to the main tunnel.

Figure 2A illustrates the below ground infrastructure

proposed. Since a permanent structure extending into the

River Thames is required, construction works would take

place within the foreshore of the River Thames. These

activities would take place within the area indicated

by the red line in Figure 1A, in five main phases, lasting

approximately four and a half years in total. The main

construction activities at this site are set out in Table 2.1.

Main tunnel

Short connection tunnel

Drop shaf t

Valve chamber

Existing Low Level Sewer No.1

Overfowweirchamber

Figure 2A: Illustration showing typical

elements of below ground infrastructure




6

Advance

works

Phase 1

Site setup

Figure reference – Figure 2C

Typical working hours Varies Standard

M a i n c o n s t r u c t i o n a c t i v i t i e s

Utilities connected ü

Utilities diverted or protected ü

Site cleared ü

Temporary works in River Thames constructed ü

Site facilities and access set up ü

Drop shaft excavated and built

Tunnel boring machine delivered to site and assembled

Short connection tunnel excavated and built

Above and below ground structures constructed

Mechanical and electrical equipment installed

Temporary works in River Thames removed

Site restored and landscaped

Temporary site facilities removed

Table 2.1: Main construction activities during construction phases

Our typical working hours are expected to be:

Standard: 8am-6pm weekdays, 8am-1pm Saturday*

Extended standard: 6pm-10pm weekdays, 1pm-5pm Saturdays

Continuous: 24 hours a day, seven days a week**

Varies: Working hours for advanced works will depend on the nature of the works and will be agreed

with the local authority

* Standard working hours would also include, subject to agreement with the local authority:– a short period (up to one hour) before works start and after they have finished to allow our workers to prepare for work and check the site.

– equipment and machinery maintenance could also take place 1pm-5pm Saturday and 10am-4pm Sunday.

** The main activities taking place 24 hours a day are below ground or within an enclosure.



Construction

7

Phase 2

Drop shaft

construction

Phase 3

Tunnelling

Phase 4

Construction of

other structures

Phase 5

Completion of

works and siterestoration

Figure 2D Figure 2D Figure 2E –

Standard Continuous Standard Standard

ü

ü

ü

ü

ü

ü

ü

ü

Related documents:

Build Managing construction




8

Site layout and construction phasesFigures 2C, 2D and 2E show how the site might be laid

out during the construction phases, which are set outin Table 2.1 and Figure 2B. These layouts have been

informed by the size of the infrastructure proposed,

the construction methods required and the location

of neighbouring buildings and structures. They have

also been developed to minimise impact on the local

community and environment. A particular factor at this

site that has influenced the layout is as follows:

•

The cofferdam structure has been located furthersouth along the River Thames foreshore away from

the Golden Jubilee footbridge/ Hungerford rail bridge

to minimise the risk of disturbance to the London

Underground Bakerloo line tunnels and reduce the

potential for effects on river flow and river services.

This also removes the need the move the Hispaniola

restaurant ship during construction works.

P1 P3

P2 P4

P5 A d v a n c e

w o r k s

Figure 2B: Construction timeline showingapproximate duration of works in phases (P)

The site layouts are indicative only, and the contractor

may arrange the site in a different way, depending onthe chosen construction methods, provided that any

environmental effects are appropriately managed and

that the main construction activities are undertaken

within the red line shown in Figure 1A.



Construction

9

Figure 2C: Illustrative phase 1 construction plan

Jack up bargeservicing pilingoperations

Two waytraffic

Initial closure of westboundcarriageway (advance

works only – diversion of underground utilities)

Tattershall

Castle to berelocated

Possible location of permanently relocatedTattershall Castle

Westbound carriagewaypartly re-opened on

completion of advance works,part closed for site access

Barge

N

Maximum extentof construction site

for phase 1Site hoarding/traffic barrier

Cofferdam

Local authorityboundary

Site support/welfare

Traffic lane coned off for site access

Site access

Existing Thames Path

Thames Path diversion

CITY OF WESTMINSTER

LAMBETH




10

Figure 2D: Illustrative phases 2 and 3 construction plan

N

Option for contractorto transport materials

using barges

Cranes

Drop shaft

Maximum extent of construction site forphases 2 and 3

Site hoarding/traffic barrier

Cofferdam

Local authority boundary


Excavated materialstorage and processing

Maintenance workshopand storage

Internal site road


Site access



CITY OF WESTMINSTER

LAMBETH

Possible location of permanently relocated

Tattershall Castle



Construction

11

Figure 2E: Illustrative phase 4 construction plan

[Tames Water to provide plan]

N

Option for contractorto transport materials

using barges

Cranes

Drop shaft

Maximum extent of construction site forphase 4

Site hoarding/traffic barrier

CofferdamLocal authorityboundary


Excavated materialstorage and processing

Maintenance

workshop and storage

Internal site road


Site access



CITY OF WESTMINSTER

LAMBETH

Possible location of

permanently relocatedTattershall Castle




12

Additional works and activitiesThe main construction activities at this site are set out in

Table 2.1. We would also need to undertake additionalworks and activities, some of which may be located

outside of the area indicated by the red line in Figure 1A.

The anticipated additional works and activities are set

out in Table 2.2.

When Type of works What we would do

Required for

construction

phase

Installation equipment

to monitor environmental

matters such as noise,

vibration and dust.

The locations of monitoring equipment would be agreed with the

local authority and relevant landowners.

Protection works to third

party structures (such as

buildings, bridges and

tunnels).

We would undertake studies to identify any effects our construction

work may have on third party structures. The studies may

recommend particular construction methods or, in very limited

instances, protection works.

Diversion of utilities.

There are two large gas mains and approximately 20 fibre optic

telecommunication cables inside the river wall, as well as small power

cables beneath the embankment footpath, all of which would require

diverting into the Victoria Embankment (A3211) carriageway to

enable the new connection to the northern Low Level Sewer No.1.

Temporary connection to

utilities (such as water, sewer,

phone and electricity supply).

We expect to connect to utilities in Victoria Embankment (A3211).

Traffic management works.

These may need to extend beyond our site and could include

relocating kerb lines, repainting road lines and modifying

traffic signals.

Dredging.

There is a possibility that as the detailed design is developed we may

need to undertake dredging to allow barges to get to and from

our site.

Protection of the riverbedWe may need to carry out works to strengthen the river bed to

avoid scour.

Required for

operationalphase

Permanent connection to

utilities (such as water, phoneand electricity supply) for the

operational tunnel.

We expect to connect to utilities in Victoria Embankment (A3211).

Table 2.2: Additional works and activities



Construction

13

Construction transport and accessWe propose to use barges to bring in and take away the

material used to fill the cofferdam. It is not generallypractical and cost effective to transport all materials

to and from the site by barge so we would still need to

transport some materials by road. We would however

give the contractor the flexibility to determine the most

practical and cost-effective means of transporting other

materials and equipment.

Each barge would remove approximately 55 lorries from

the road. Using barges at this site would reduce thenumber of lorry visits to/from this site by approximately

45% (saving 16,000 lorry visits over the construction

period of approximately four and a half years). Table 2.3

sets out the anticipated average daily number of lorries

and barges visiting (ie travelling to and from) the site

during the peak months of each phase, based on moving

cofferdam fill material by barge.

Construction traffic would access the site along thewestbound carriageway of Victoria Embankment

(A3211), turning left into the site through a new entrance.

The site access points are shown on Figures 2C, 2D

and 2E. Traffic leaving the site would turn left onto the

westbound carriageway of the Victoria Embankment

(A3211) from a second new exit.

Beyond this, construction traffic would use the major road

network to get to and from its final destination.We would need to close one westbound lane of the

Victoria Embankment (A3211) (which is currently used

for coach and car parking off peak) to provide site access

during construction. When the utilities are diverted during

our advance construction works, we would need to close

the remaining westbound carriageway of the Victoria

Embankment (A3211) and divert westbound traffic onto

one of the lanes in the eastbound carriageway, as shownon Figure 2C.

The Thames Path runs through our construction site. We

would create a temporary diversion for the duration of

our works as indicated on Figures 2C, 2D and 2E. Based

on our current design, we do not anticipate that any bus

stop relocations or junction changes would be required.

Phase 1Site setup

Phase 2Drop shaft

construction

Phase 3Tunnelling

Phase 4Construction

of otherstructures

Phase 5Completion of works and site

restoration

Average daily

lorry visits15 lorries 23 lorries 5 lorries 16 lorries 16 lorries

Average dailybarge visits

3 barges none none none 2 barges

Table 2.3: Average daily lorry and barge visits during the peak months

Related documents:

Transport




14

Management of construction worksOur construction works would be managed in accordance

with an agreed Code of construction practice (CoCP).For phase two consultation, we have produced a draft

CoCP Part A: General requirements, informed by CoCPs

from other major construction projects in London and

consultation with the local authorities. Through the

environmental impact assessment process, scheme-

wide principles to address potential effects on the local

environment have been identified and integrated into

the design. The CoCP Part A sets out scheme-wide control

measures that would be used to minimise potentialeffects during the construction process.

Table 2.4 sets out what we consider to be the key issues

for this site during construction, and how we are currently

proposing to address them.

Issue Our response

Construction activities will require thepermanent relocation of the Tattershall

Castle floating bar and restaurant.

We will be consulting with the owners of the vessel, Westminster CityCouncil and the Port of London Authority to enable its permanent relocation

during construction.

Possible effects on the Grade II listed

embankment including the wall,

sturgeon lamps, festoon lighting

columns and ‘sphinx’ seat.

The embankment wall will be partly removed with its historic features

dismantled, protected and stored. The remaining wall would be suitably

protected during construction.

Possible effect of temporary road

restrictions and construction vehicles

on the volume of traffic on the Victoria

Embankment (A3211).

We have sought to minimise disruption to the local road network throughour site layout, design and phasing of our construction works. During

construction, two-way traffic along the Victoria Embankment (A3211)

would be maintained. We would manage the effects of road transport

through our traffic management plans, which will seek to limit the number

of vehicle movements and hours of operation, identify the most suitable

site access points and any necessary highway management arrangements.

As already set out, we also propose to use barges to bring in and take away

the material used to fill the cofferdam, which would reduce the number of

lorry movements from this site by approximately 45% over the construction

period.

Related documents:

Environment

Managing construction

Transport



Construction

15

Issue Our response

Temporary diversion of the Thames Path.The Thames Path would be temporarily diverted away from the RiverThames via a safe alternative route to the west of Victoria Embankment

(A3211).

Possible effect of temporary cofferdamon river traffic services operating from

Embankment Pier.

Since phase one consultation the cofferdam has been relocated further

south, away from the Hungerford Bridge, to reduce potential effects on river

flow and river services. This also removes the need to move the Hispaniola

restaurant ship during construction works.

We will continue to liaise with the Port of London Authority and Thames

Clippers to reduce these effects.

We have undertaken modelling to test the effect that the structure has on

the flow of the river. The modelling has shown the proposed structure to be

satisfactory and the Port of London Authority and other key stakeholders

are satisfied the permanent works have a minimum effect on river

navigation. A full navigational risk assessment will be undertaken for the

temporary and permanent works.

Possible effect of noise and vibration on

neighbouring areas from construction

activities and short term 24 hour

tunnelling.

The contractor would be required to implement noise and vibration control

measures at the worksite, which will be set out in the CoCP. Continuous

tunnelling would only be undertaken for a short period of time to construct

a connection tunnel from the drop shaft to the main tunnel.

Possible effects on local air quality and

dust nuisance in neighbouring areas.

Preliminary findings indicate that while there is the potential for dust

nuisance effects, there are unlikely to be any significant local air quality

effects at any of the sites. The contractor would put in place air and dust

control measures at the worksite, which will be set out in the CoCP.

Possible effects of construction activities

on the existing pipe subway and

underground railway lines.

Nearby buildings, bridges and tunnels would be monitored where

applicable throughout the construction period. Other specific construction

management measures for this site would be agreed with the relevant

owners of the structures.

Table 2.4: Key issues relating to construction

Vi t i E b k t F h




16

Section 3: Future use

This section describes the site after the completion of the

construction work, ie when the main tunnel is in use – the

‘operational phase’.

Design

Since phase one consultation we have progressed the

design for the permanent use and appearance of the

structures at Victoria Embankment Foreshore. The design

of the permanent proposals follows our scheme-wideprinciples and takes into account comments made and

ongoing engagement with Westminster City Council and

other technical consultees.

Our permanent works, which are formed within a structure

extending into the foreshore of the River Thames, need

to incorporate functional elements which are required for

the operation of the main tunnel. These include:

•

Underground structures with ground level access coversincluding: a CSO drop shaft with an internal diameter

of approximately 16m, connection tunnel to the main

tunnel, valve chamber, passive filter chamber and an

overflow weir chamber to divert flow from the northern

Low Level Sewer No.1.

•Two main ventilation columns up to 6m high.

•A small diameter ventilation column to the interception

chamber up to 6m high.•Maintenance vehicle access.

•Electrical and control kiosks.

Table 3.1 sets out the site specific issues that have

influenced our permanent design proposals and how we

have addressed them in our proposed design.

Issue Our response

Preserving the existing

design of the Grade II

listed embankment (by

Bazalgette).

The proposed structure is rectangular in shape to reflect other 19th Century elements

of Bazalgette’s embankment, including the RAF memorial/Whitehall Steps and

Cleopatra’s Needle.

The proposed materials would complement those of the embankment while making it clear

that a new extension to it had been formed.

The effect on the

historic setting of

the site, including

views along the River

Thames to the Palace of

Westminster.

The proposed new public space would be aligned with the existing Victoria Embankment

Gardens in order to provide a visual link between the two spaces.

Stone piers would be used to mark where the embankment walls end; these would house

our electrical and control kiosks.

Lighting on the new structure would be provided at ground level in order to minimise light

spill onto the River Thames and not detract from the night view of the row of festoon

lighting from the south.

The ventilation columns, in common with the scheme-wide ventilation strategy, are thinner

and shorter than those proposed at phase one consultation.



F u t ur e

u s e

Future use

17

Issue Our response

New design requires the

permanent relocation

of the Tattershall

Castle floating bar and

restaurant.

We are currently proposing to relocate the existing mooring to the south near Horse Guards

Avenue. This will be subject to further consultation with the owners of the Tattershall Castle,

Westminster City Council and the Port of London Authority.

Effects on river

navigation and

hydraulics.

Preliminary modelling has indicated that the proposed design is acceptable in terms of

river flow.

The proposals have been discussed with the Port of London Authority and other key

stakeholders to develop a layout that has a minimal effect on river navigation.

The surrounding area

attracts large numbers

of tourists with coach

parking located

adjacent to the site.

The overall design would create a new accessible area of public space away from the traffic

of Victoria Embankment, for people to enjoy the River Thames and views towards the

Palace of Westminster.

Location of LondonUnderground Bakerloo

line and District and

Circle lines tunnels.

The works are located in the River Thames in order to avoid affecting the District and Circle

lines tunnel.

The location of our proposed permanent works in the foreshore has moved to the south in

order to provide a safe distance from the Bakerloo line tunnels.

Loss of foreshore

habitat and effects on

ecology.

Our proposals for the permanent layout and design of the site have sought to reduce

the extent of the permanent works within the River Thames to minimise effects on water

ecology as far as possible.

Ecological surveys of the River Thames are being undertaken to identify possible effects,and design measures would be incorporated where required.

Construction of the tunnel would deliver river wide improvements to local water quality,

which would result in positive effects on river ecology, including habitat improvements and

reduced fish kills.

Table 3.1: Site specific issues that have influenced our permanent design





18

Figure 3A: Photo of the site – before the works

Figures 3A, 3B, 3C and 3D show the current site and

provide illustrations of our design proposals. Further

information on the development of our design can be

found in the Design development repor t.

Related documents:

Design

Future use



Future use

19

Figure 3B: Artist’s impression of the site – after the works are completed





20

Figure 3C: Aerial view of the completed works

Future use



Future use

21

Figure 3D: Layout of site once construction works complete

Viewing platforms

along southern edge

Ramps provide

step free access to

viewing platformGranite paving

Stone clad electrical

and control kiosks

Central section of canopy removable for

maintenance access

Canopy planted

with jasmine

New Regent Street

CSO outlet

Ventilation columns

Access hatches with

brass inlay panels

Replacement

tree planting

Raised viewing platform

with balustrade edge

protection and stone

seating

V i c t o

r i a E

m b

a n k

m e n t

N





22

Operation and maintenanceOnce the tunnel is operational, we would need access

to the site occasionally for inspection and maintenance

purposes. We expect to visit the site approximately

once every three to six months to carry out inspections

and maintenance of the ventilation and below ground

equipment. This is likely to involve a visit by staff in a

small van, and may take several hours.

Once every ten years, we expect to carry out a major

internal inspection of the tunnel and underground

structures. This is likely to involve a small team of

inspection staff, a small team of support crew and

two mobile cranes to lower the team into the shaft.

This is likely to take several days and we would require

temporary fencing around the shaft for safety and

security while the inspection takes place.

We may also need to make visits to the site for unplanned

maintenance or repairs, for example, if there is a blockage

or equipment failure. This may require the use of mobile

cranes and vans.

Permanent vehicular access would be from Victoria

Embankment (A3211).

Management of operational effectsWe have undertaken technical work, including stakeholder

engagement, to assess and identify the key issues

associated with this site once it is operational. Table

3.2 summarises these issues and how we are currently

proposing to address them.

Future use



23

Issue Our response

Possible odour effects during the

operation of the tunnel.

Odour effects at this site are expected to be negligible because we have developed

an Air management plan to minimise possible odour and air quality effects arising

from the operation of the tunnel. The technology we are proposing to use at this

site includes the use of passive below ground carbon filters that would remove

possible odour before air leaves the ventilation equipment.

Disturbance from futuremaintenance access.

Permanent access would be required for maintenance and servicing purposes

to the shaft and ventilation equipment. Any planned maintenance visits would

be undertaken during normal working hours and all visits managed to avoiddisruption to local residents, businesses and users of affected public areas as far as

possible.

Table 3.2: Key issues relating to site operation

Related documents:

Odour

Further information



24

Further information

This section sets out documents which may be of particular interest. Further information on our proposals can be

found on our website (www.thamestunnelconsultation.co.uk) or is available upon request (call our customer centre

on 0800 0721 086).

Phase two public consultation material

Project information papers include general information about the Thames Tunnel project. There are 17 project

information papers, which cover various aspects of the project. Those project information papers that may be of

particular interest are set out below.

Icon Title Details

Build

Provides information on the different types of sites required for the Thames Tunnel

project and the typical construction activities that will be undertaken at each site.

Q&A Consultation

Sets out the consultation we have undertaken to date on the project, the scope

of this phase two consultation and how interested parties can respond to this

consultation.

Design

Contains the design principles which have influenced the permanent appearance of

our sites once construction work is complete.

EnvironmentSets out the process the project is following to assess potential environmental effects

of the Thames Tunnel project.

Managing

construction

Includes information on what measures our contractors will put in place at our sites

during construction.

Odour Sets out our Air management plan and how it will work.

Options Outlines the various ways to deal with sewage overflows.



Further information



26

u t e o at o

Technical reports

Theme Icon Title Details

Phase one

consultation1

SUMMARY

Report on phase one

consultation:

summary report

Provides a summary of the comments made at phase one

consultation and our responses.

Phase two

construction

information

Code of construction

practice Part A:

General requirements

(CoCP)

Sets out control measures to be adopted during the project

construction period.

Phase two

environmental

information

Air management

plan

Outlines the methods which we will use to manage odour

from the main tunnel at all our preferred sites.

Preliminary

environmental

information report

(PEIR)

Contains initial assessments on the environmental effects of

the Thames Tunnel project based on information collected

to date. Please refer to volume 20 of the non-technical

summary and volume 20 of the PEIR for more informationon this site.

Phase two scheme

development

Design development

report

Provides a general overview of how the scheme design at

each site has evolved to date. Please refer to chapter 18 for

more information on this site.

2

Phase two scheme

development report

Provides an overview of the development of the Thames

Tunnel project and how each site was chosen. Please refer to

Appendix P for more information on this site.

Site glossary



27

g y

Term Definition

Carbon filters Filters that remove odours before the air is released from the tunnel.

CofferdamA wall that is constructed within the river around the outside of the working area and then

pumped dry. The inside of the cofferdam can then be filled to create a safe working area.

Combined sewer A single sewer system that takes both rainwater and domestic and industrial wastewater.

Combined sewer

overflow (CSO)

A structure, or series of structures, that allows sewers to overflow into the river when they

are full as a result of increased rainfall. Without the overflows, the sewers would back up and

cause flooding in streets or houses.

Connection tunnel A tunnel connecting a drop shaft to the main tunnel.

Conservation areaAn area designated by the local authority or English Heritage as having special architecturalor historical interest.

Draft limit of land to

be acquired or used

The extent of land that we may need to use or acquire, or over which rights may be needed to

carry out works that are essential to the project.

Drop shaft

A vertical circular concrete structure, used to drop flows from the high level of the CSO to

the low level of the main tunnel. It would also be used to provide access to construct the

connection tunnels.

Foreshore Ground uncovered by the river when the tide is low.

Interception chamberA structure, built on an existing combined sewer, which diverts stormwater overflow into the

main tunnel.

Main tunnel The tunnel from Acton Storm Tanks to Abbey Mills Pumping Station.

Operational phase After the completion of the construction work, when the main tunnel is in use.

Scour Movement of the riverbed materials due to the force of the water.

Thames Tunnel project

The Thames Tunnel project comprises a storage and transfer tunnel, from west London to

Beckton Sewage Treatment Works in east London, and the control of 34 CSOs along theThames Tideway.

Transport for London

Road Network (TLRN)

The network of roads managed by Transport for London. These are the major or ‘strategic’

roads, which have high capacity.



Phase two consultation: Victoria Embankment Foreshore

For further information or to comment on ourproposals see our website:

www.thamestunnelconsultation.co.uk

110-ED-PNC-00000-000091

Autumn 2011

It is very important that you understand theinformation we have provided. If you needfurther information in another language,

braille, large print or audio format pleasecontact us on 0800 0721 086.

p2 victoria embankment foreshore sip

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