P2 Blackfriars Bridge SIP

8/3/2019 P2 Blackfriars Bridge SIP

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Introd

uction

Introd

uction

Thames Tunnel

Blackfriars BridgeForeshore

Currently, untreated sewage regularly overows into the River Thames from Londons 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 ofthe River Thames. In order to deliver the project we need a number of sites along the route and this documentidenties our current preferred sites at Blackfriars Bridge Foreshore.

Siteinformationpaper

1

Key facts

Local authority: City of London

CSO name: Fleet MainCSO spill volume in an average year: 520,000m (equivalent to approximately

208 Olympic swimming pools)

Site type: CSO site

Duration of main construction works: Approximately ve years.


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Blackfriars Bridge Foreshore

2

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

extends into the River Thames, directly under and to thewest of Blackfriars Bridge. Part of the site extends north

onto the Victoria Embankment (A3211), along which the

Thames Path is located. To the north and across Victoria

Embankment (A3211) is a mix of offices and hotels. The

President ship is moored beyond Blackfriars Millennium

Pier to the west. The site is within the Whitefriars

Conservation Area.

The permanent site area would include the structuresassociated with the Blackfriars Millennium Pier, which

would be removed and permanently reinstated to the

east of the railway bridge on Pauls Walk, as illustrated on

Figure 1A.

This site information paper sets out our proposals at

Blackfriars Bridge Foreshore. We have also produced

project information papers, which cover overarching

topics relating to the project. Where we consider that aproject 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.

We are proposing to reclaim an area of the River Thames,

adjacent to Blackfriars Bridge for this construction workand to accommodate permanent structures required

to operate the main tunnel. The site would be used to

intercept the existing local CSO, known as the Fleet Main

CSO, and connect to the northern Low Level Sewer No.1 to

divert flows to the main tunnel.

These works, along with our works at Victoria

Embankment Foreshore and Chelsea Embankment

Foreshore 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.

Section 1: Introduction and site information

Related documents:

Build


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Introduction

3

Figure 1A: Blackfriars Bridge Foreshore location plan

N

Low LevelSewer No.1

Fleet Main CSO

Inner TempleGarden

Temple Place

Blackfriars

Rail Bridge

BlackfriarsStation

Blackfriars

Bridge

Blackfriars

Millennium Pier

VictoriaEmbankment

SOUTHWARKLAMBETH

CITY OF LONDON

Local authority boundary

Draft limit of land to beacquired or used

Proposed tunnelroute centreline

Existing sewer

Existing CSO

Tem

ple

Avenue


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4

How we chose this site

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

Blackfriars Bridge Foreshore to intercept the Fleet Main

CSO and connect the northern Low Level Sewer No.1

to the main tunnel. At phase one consultation, which

was held between September 2010 and January 2011,

Blackfriars Bridge Foreshore was presented as our

preferred site. We assessed other sites but none made it

through to the shortlist stage of the site selection process.

What we are proposing at phase two consultationWe have considered the comments from phase one

consultation, feedback from ongoing engagement and

new information; and undertaken further technical work.

We still consider that Blackfriars Bridge Foreshore should

be our preferred site because Blackfriars Bridge Foreshoreis the only location where we can both intercept the Fleet

Main CSO and connect the northern Low Level Sewer No.1

to the main tunnel.

Related documents:

Q&A Consultation

Site selection


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Construction

Construction

5

Section 2: Construction

Construction activitiesConstruction activities are required to intercept the CSO

and connect the northern Low Level Sewer No.1 to the

main tunnel. We would construct an interception chamber

to intercept the CSO. A connection culvert would link the

interception chamber to a drop shaft (approximately

53m deep), through which flows would drop into the

main tunnel. We would also construct an overflow weir

chamber which would allow flows to be transferred from

the northern Low Level Sewer No.1 down the same

drop shaft.

Main tunnel

Drop shaft

Valve chamber

Existingoverfow to

River ThamesInterception

chamber

Existing overfow sewerExisting LowLevel Sewer No.1

Overfow weir chamber

Figure 2A: Illustration showing typical elements of below ground infrastructure

As the construction works would take place within the

foreshore of the River Thames, permanent structures

extending into the foreshore are required. Figure 2A

illustrates the below ground infrastructure proposed.

These activities would take place within the area

indicated by the red line in Figure 1A, in four main phases,

lasting approximately five years in total. The main

construction activities associated with these phases are

set out in Table 2.1.


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6

Advance works

Phase 1

Site setup

Figure reference Figure 2C Figure 2C

Typical working hours Varies Standard

Mainconstructionactivities

Utilities connected

Utilities diverted or protected

Pier relocated

Site cleared

Temporary works in the River Thames constructed

Site facilities and access set up

Drop shaft excavated and built

Above and below ground structures constructed

Mechanical and electrical equipment installed

Temporary works in the River Thames removed

Site restored and landscaped

Temporary site facilities removed

Table 2.1: Main 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.


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Construction

7

Phase 2

Drop shaft

construction

Phase 3

Construction of

other structures

Phase 4

Completion of works

and site restoration

Figure 2D Figure 2E

Standard with

occasional extended

standard

Standard Standard

Related documents:

Build

Managing construction


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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 effects on the local

community and environment. Particular factors at this site

that have influenced the layout are as follows:

Since our phase one consultation we have increasedthe drop shaft in size from approximately 20m to 24m

in internal diameter as a result of further physical

modelling of the shaft.

Part of the site would be constructed on piles to

minimise the effects on river ecology compared to other

construction options.

The layout of the site has been designed to reduce

effects on the navigation of the River Thames.

The connection to the northern Low Level Sewer No.1

has moved to beneath the existing Blackfriars Bridge

ramp to minimise the effects on existing utilities

running within the Victoria Embankment (A3211).

P1 P3

P2 P4

Year 1 Year 2 Year 3 Year 4 Year 5

Advance

works

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 undertake within

the red line shown in Figure 1A.

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


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Construction

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Jack up bargeservicing pilingoperations

Working area for pierrelocation (advance

works only)

NSOUTHWARK

CITY OF LONDON

LAMBETH

Diversion rejoins

Thames Path atTemple Place

Possible locationof President duringconstruction

Existing mooringfor President

Barge

Figure 2C: Illustrative advance works and phase 1 construction plan

Maximum extent ofconstruction site foradvance works and phase 1

Site hoarding/traffic barrier

Cofferdam


Site support/welfare

Traffic lane coned off for site access

Site access

Existing Thames Path

Thames Path diversion

BlackfriarsBridge

BlackfriarsRail Bridge

BlackfriarsStationVictoria Embankment


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Figure 2D: Illustrative phase 2 construction plan

Option for contractorto transport materialsusing barges

Piling rig Cranes

Drop shaft

N

Maximum extent ofconstruction site for phase 2


Cofferdam



Excavated materialstorage and processing

Maintenance workshopand storage

Construction support

Internal site road

SOUTHWARK

CITY OF LONDON

LAMBETH

Diversion rejoins



Traffic lane coned offfor site access

Site access



BlackfriarsStation

BlackfriarsBridge



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Construction

11

Figure 2E: Illustrative phase 3 construction plan

Option for contractorto transport materialsusing barges

Cranes

CraneDrop shaft

N

Maximum extent ofconstruction site for phase 3


Cofferdam



Maintenance workshop and storage

Internal site road

Site access



CITY OF LONDON

SOUTHWARKLAMBETH


BlackfriarsStation

BlackfriarsBridge


Diversion rejoins



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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 of equipment to monitorenvironmental matters such as noise,

vibration and dust.

The locations of monitoring equipment would be agreedwith 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.

If protection works are required to the existing sewer,

we would access the sewer network through existingmanholes.

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 would 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 isdeveloped we may need to undertake dredging to allow

barges to get to and from our site and for the relocated

Millennium Pier.

Protection of the river.We may need to carry out works to strengthen the river

bed to avoid scour.

Required for

operational

phase

Permanent connection to utilities (such as

water, phone and electricity supply) for the

operational tunnel.

We expect to connect to utilities in Victoria

Embankment (A3211).

Table 2.2: Additional works and activities


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Construction

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

material used to fill the cofferdam. Each barge wouldremove approximately 55 lorries from the road. Using

barges at this site would reduce the number of lorry visits

to/from this site by approximately 45% (saving 14,500

lorry visits over the construction period of approximately

five 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.

During phases 1 and 2 of construction, construction

traffic would access the site travelling across Blackfriars

Bridge and turning left into the site through a new

entrance from the westbound ramp leading down from

Blackfriars Bridge. Traffic leaving the site would turn left

from a second new entrance then merge onto Victoria

Embankment (A3211) and continue westbound.

During construction phase 3, the westbound ramp fromBlackfriars Bridge would be closed. Construction traffic

would access the site by turning left from the Blackfriars

underpass, and would leave the site by the same route

as for the other construction phases. Beyond this,

construction traffic would use the major road network to

get to and from its final destination. Site access points

are shown on Figures 2C, 2D and 2E.

During construction phase 3, general traffic that would

normally use the westbound ramp from Blackfriars Bridgewould be diverted as shown in Figure 2F.

We would need to suspend some coach parking bays on

the westbound ramp from Blackfriars Bridge and some

loading bays on Victoria Embankment (A3211) during

construction.

The Thames Path runs through our construction site. We

would create a temporary diversion for the duration of

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

our current design we do not anticipate that any other

footpath or bus stop relocations would be required.

Phase 1Site setup

Phase 2Drop shaft

construction

Phase 3Construction ofother structures

Phase 4Completion ofworks and site

restoration

Average daily lorry visits 21 lorries 35 lorries 29 lorries 6 lorries

Average daily barge visits 2 barges none none 3 barges

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

Related documents:

Transport


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Figure 2F: Proposed diversion for westbound ramp from Blackfriars Bridge

SOUTHWARKLAMBETH

CITY OF LONDONWESTMINSTER

N

Diversion route

Local authority

boundary

WestminsterBridge

WaterlooBridge

BlackfriarsBridge

BlackfriarsRail Bridge London

BridgeMillenium

Bridge

Golden JubileeFootbridges

Hungerford

Bridge


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Construction

15

Related documents:

Environment

Managing construction

Transport

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 CoCPsfrom 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.

Bl kf i B id F h


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Table 2.4: Key issues relating to construction

Issue Our response

Construction activities would

require the temporary relocation

of the President ship and

the permanent relocation of

Blackfriars Millennium Pier.

The President ship would be temporarily moved west to the formerChrysanthemum Pier moorings. Blackfriars Millennium Pier would be relocated to

the east of Blackfriars Bridge.

Possible effect of construction

vehicles on the volume of traffic

on Victoria Embankment (A3211).

We have sought to minimise disruption to the local road network through our

site layout, design and phasing of our construction works. 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.

Temporary diversion of the

Thames Path.

The Thames Path would be temporarily diverted via a safe alternative route along

the northern footpath to Victoria Embankment (A3211), and back to the Thames

Path via steps and a temporary lift to the east of Blackfriars Bridge.

Possible effect of foreshore

construction activities on river

navigation and river users.

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 from construction

activities on neighbouring areas.

The contractor would be required to implement noise and vibration control

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

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.


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Future

use

Future use

17

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 our phase one consultation we have progressed

the design for the permanent use and appearance of

the structures at Blackfriars Bridge Foreshore. The design

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

ongoing engagement with the City of London 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 tunnel. These include:

Underground structures with ground level access covers

including: a CSO drop shaft with an internal diameter

of approximately 24m, connection culverts, interception

chamber, valve chamber, passive filter chamber and an

overflow weir chamber to divert flow from the northern

Low Level Sewer No.1.

Five 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 haveinfluenced our permanent design proposals and how we

have addressed them in our proposed design.



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Issue Our response

Effect on the historic setting of

the site including views alongthe River Thames towards St

Pauls Cathedral.

The form of the proposed structure in the foreshore of the River Thames is

contemporary and seeks to resolve the level differences created by the Thames Path

and the Blackfriars Bridge approach ramp.

The structure is designed to allow unhindered views of the listed buildings located

along Victoria Embankment (A3211) and views towards St Pauls Cathedral. In

addition, new views of the River Thames would be offered from the viewing platforms

created on the new structure.

The proposed materials would complement those of the Embankment and the listed

buildings located close to the site while making it clear that we have created a newextension into the River Thames.

The historic line of trees (London Planes) along the Embankment would be extended

onto the new structure to help create areas of shade.

As a result in the change to the ventilation strategy we no longer need a large

ventilation building on the site as was indicated at phase one consultation.

Ventilation of the tunnel is still required, and in this location we have designed a

series of five smaller columns that form a feature on the proposed landscape whilstmeeting our operational requirements to manage the air in the main tunnel.

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.

Effect on the Thames Path.

The Thames Path would be restored after our works are complete and would be

central to the proposed new landscaped public area, where people can stop to enjoy

the River Thames.

The proposals would enhance the Thames Path which is currently characterised by a

number of narrow ramps and stairs in this location.

Our design allows a flat and fairly direct pedestrian route from the western access

point on Victoria Embankment (A3211) to the eastern access on Pauls Walk beneath

the road bridge, while offering opportunities to step to the side and ascend ramps or

stairs to rest, enjoy the views or walk up to Blackfriars Bridge or Blackfriars Station.

Future use


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Future use

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Issue Our response

Effect on river based business

and passenger services from

Blackfriars Millennium Pier.

It is proposed to permanently relocate Blackfriars Millennium Pier to the east of theBlackfriars Railway Bridge.

The shape of the structure to intercept the Fleet CSO has been designed to ensure

that it does not impede the navigational channel of the River Thames in this

location.

Following completion of the works the President ship would be restored from its

temporary location during the construction works to its current mooring to the west

of the new structure.

An alternative location onshore would be found for Crown River Cruises, who are

currently located on Blackfriars Millennium Pier.

Loss of foreshore habitat andeffects 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 to minimise effects on water

ecology as far as possible.

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

Construction of the tunnel would also 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 elements and issues that have influenced our permanent design



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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 report.

Related documents:

Design

Future use


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Future use

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Figure 3B: Artists impression of the site after the works are completed



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Figure 3C: Aerial view of the completed works

Future use


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Figure 3D: Layout of site once construction works complete

President reinstatedin current positionat the end of

construction period

Ventilationcolumns

Provision

for smallretail kiosk

Access for

maintenancevehicles

Stepped platformand seating area

Level Thames Path

over new foreshorestructure

Raised viewingplatform

VictoriaEmbankment

BlackfriarsBridge

Ramp providesstep free access toviewing platform

New water featurein paving surfacein the shape of the

River Thames

Widened

pedestrian routeunder bridge

Stairs from

BlackfriarsBridge reinstated

Foreshore structureto extend underbridge deck

N

Electrical and control kioskunder vehicle ramp fromBlackfriars Bridge

New entrance topublic WCs and privatesporting facility

New FleetCSO outlet

Refer to detail below

Millennium pierpermanently relocated



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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. 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 and inspection vehicle into the shaft. This is

likely to take several weeks, and 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


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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 developedanAir management plan to minimise possible odour and air quality effects arisingfrom 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 will remove

possible odour before air leaves the ventilation equipment.

Disturbance from future

maintenance 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 avoid disruption

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


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Phase two public consultation material

Icon Title Details

OverflowSets out how Londons sewerage system works and why the capital has an overflow

problem.

Route and

tunnel

alignment

Sets out the preferred route of the main tunnel and the reasons for our preference.

Site selection Sets out the process we followed to find and select our preferred sites.

Transport Contains information on the different transport options we have considered fordelivering and removing materials from our sites.

Further information


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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 21 of the non-technical

summary and volume 21 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.

2Phase two schemedevelopment report

Provides an overview of the development of the Thames

Tunnel project and how each site was chosen. Please refer toAppendix Q for more information on this site.

Site glossary


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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

architectural or 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 the

Thames 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.


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P2 Blackfriars Bridge SIP

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