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Preliminary environmentalinformation reportVolume 2: Proposed development
Regulations 2 and 10 of the Infrastructure Planning(Environmental Impact Assessment) Regulations 2009
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Phase two consultation documentation
Project informationpapers
Build Changes Consultation Design Environment Funding Managing construction Odour Options Over ow Regulatory framework Route and tunnel alignment Route to consent Settlement Site selection
Timing Transport
Technical documents Air management plan Book of plans Code of construction practice
Part A: General requirements Consultation strategy and statement of
community consultation Design development report Draft waste strategy Interim engagement report
Needs Report Phase two scheme development report Preliminary environmental information report Report on phase one consultation Background technical paper Site selection methodology paper
Site information papers Abbey Mills Pumping
Station Acton Storm Tanks Albert Embankment
Foreshore Barn Elms Beckton Sewage
Treatment Works Bekesbourne Street Blackfriars Bridge
Foreshore Carnwarth Road
Riverside Chambers Wharf Chelsea Embankment
Foreshore Cremorne Wharf Depot Deptford Chrurch Street
Dormay Street Earl Pumping Station
Falconbrook PumpingStation
Greenwich PumpingStation
Hammersmith PumpingStation
Heathwall PumpingStation
Jews Row
King Edward MemorialPark Forehore King Georges Park Kirtling Street Other works Putney Bridge Foreshore Shad Thames Pumping
Station Victoria Embankment
Foreshore
General Your guide to phase two
consultation Why does London need the
Thames Tunnel? Feedback form Equalities form Customer overview lea et
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Page i Preliminary environmental informationreport
Thames Tunnel
Preliminary environmental information report
List of contents
Non technical summary
Part A: Preliminary project information
Volume 1 Introduction
Volume 2
Volume 3
Proposed development (this document)
Alternatives
Volume 4 Scoping Opinions and technical engagement
Volume 5 Assessment methodology Volume 6 Project-wide assessment
Part B: Preliminary site information
Volume 7 Acton Storm Tanks CSO interception and main tunnel reception site
Volume 8 Hammersmith Pumping Station CSO interception site
Volume 9 Barn Elms CSO interception site
Volume 10 Putney Bridge Foreshore CSO interception site
Volume 11 Dormay Street CSO interception and connection tunnel sequential drive
siteVolume 12 King Georges Park CSO interception and connection tunnel reception
site
Volume 13 Carnwath Road Riverside main tunnel drive and reception, andconnection tunnel reception site
Volume 14 Falconbrook Pumping Station CSO interception site
Volume 15 Cremorne Wharf Depot CSO interception site
Volume 16 Chelsea Embankment Foreshore CSO interception site
Volume 17 Kirtling Street main tunnel double drive site
Volume 18 Heathwall Pumping Station CSO interception site
Volume 19 Albert Embankment Foreshore CSO interception site
Volume 20 Victoria Embankment Foreshore CSO interception site
Volume 21 Blackfriars Bridge Foreshore CSO interception site
Volume 22 Chambers Wharf main tunnel drive and reception, and connectiontunnel reception site
Volume 23 King Edward Memorial Park CSO interception site
Volume 24 Earl Pumping Station CSO interception site
Volume 25 Deptford Church Street CSO interception site
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Volume 26 Greenwich Pumping Station CSO interception and connection tunneldrive site
Volume 27 Abbey Mills Pumping Station main tunnel reception site
Volume 28 Beckton Sewage Treatment Works site
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Thames Tunnel
Preliminary environmental information report
Volume 2: Proposed developmentList of contents
Page number
1 Introduction ...................................................................................................... 1
2 Need for the project ......................................................................................... 2
2.1 Introduction .............................................................................................. 2
2.2 Background ............................................................................................. 2
2.3 Legislative requirements .......................................................................... 4
2.4 Government response ............................................................................. 5
2.5 Water quality impacts .............................................................................. 6
2.6 The long term effect of doing nothing ...................................................... 8
2.7 Conclusion on need ................................................................................. 9
3 Background documents ................................................................................ 11
3.1 Introduction ............................................................................................ 11
3.2 Strategic documents .............................................................................. 11
3.3 Phase one consultation documents ....................................................... 12
3.4 Phase two consultation documents ....................................................... 12
4 Strategic planning context ............................................................................ 13
4.1 Introduction ............................................................................................ 13
4.2 National planning context ...................................................................... 13
4.3 Regional planning context ..................................................................... 14
4.4 Local planning context ........................................................................... 15
5 Project description ......................................................................................... 22
5.1 Introduction ............................................................................................ 22
5.2 Overview of the phase two preferred scheme ....................................... 22
5.3 Construction logistics ............................................................................. 43
5.4 Code of Construction Practice ............................................................... 64
5.5 Operational logistics .............................................................................. 65
5.6 Other works ........................................................................................... 80
5.7 Environmental management and monitoring plan ................................. 89
Appendix A : Draft Code of Construction Practice Part A .................................. 90
Appendix B : Local planning policies relevant to sites ...................................... 91
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Appendix C : Draft Waste Strategy Executive summary ................................... 124
Glossary ................................................................................................................ 128
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List of figures
Page number
Vol 2 Figure 5.2.1 Thames Tunnel preferred route and sites ................................... 27Vol 2 Figure 5.2.2 Isometric view of CSO interception arrangements ..................... 33
Vol 2 Figure 5.2.3 Typical layout of a main tunnel drive site .................................... 35
Vol 2 Figure 5.2.4 Typical layout of a foreshore CSO site ....................................... 36
Vol 2 Figure 5.2.5 Typical layout of an inland CSO site ........................................... 36
Vol 2 Figure 5.3.1 The elements of constructing a tunnel using a TBM ................... 45
Vol 2 Figure 5.3.2 Main tunnel drive summary ........................................................ 46
Vol 2 Figure 5.3.3 Excavated material by strata ...................................................... 54
Vol 2 Figure 5.3.4 Indicative material deliveries by type to construction sites ......... 59
Vol 2 Figure 5.3.5 Summary of material deliveries .................................................. 60
Vol 2 Figure 5.5.1 Ventilation plant locations ........................................................... 70
Vol 2 Figure 5.5.2 Typical schematic arrangement for active ventilation plant ........ 72
Vol 2 Figure 5.5.3 Typical schematic arrangement for passive ventilation .............. 75
Vol 2 Figure 5.6.1 Holloway CSO weir, Bekesbourne Street - construction ............ 81
Vol 2 Figure 5.6.2 Holloway CSO weir, Bekesbourne Street - permanent works .... 81
Vol 2 Figure 5.6.3 Shad Thames Pumping Station - construction ........................... 81Vol 2 Figure 5.6.4 Shad Thames Pumping Station - permanent works ................... 81
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List of tables
Page number
Vol 2 Table 5.2.1 Method of flow control for each CSO and CSO site locations ...... 23
Vol 2 Table 5.2.2 Summary of main tunnel components ......................................... 28Vol 2 Table 5.2.3 Summary of long connection tunnel components ........................ 30
Vol 2 Table 5.2.4 Summary of main tunnel drive and reception sites ...................... 37
Vol 2 Table 5.2.5 Summary of connection tunnel and CSO interception sites ......... 38
Vol 2 Table 5.3.1 Main tunnel drives summary ........................................................ 47
Vol 2 Table 5.3.2 Long connection tunnel drive length summary ............................ 47
Vol 2 Table 5.3.3 Short connection tunnels summary ............................................. 48
Vol 2 Table 5.3.4 Excavated quantities by strata type at construction sites (m 3) ..... 53
Vol 2 Table 5.3.5 Phase two consultation logistics strategy .................................... 55
Vol 2 Table 5.5.1 Tunnel operation scenarios for a typical year .............................. 71
Vol 2 Table 5.5.2 Typical maintenance needs at mechanical ventilation plant ........ 77
Vol 2 Table 5.5.3 Typical maintenance requirements at passive ventilation plant ... 78
Vol 2 Table 5.6.1 Minor works - working hours ........................................................ 83
Vol 2 Table 5.6.2 Shad Thames Pumping Station - working hours .......................... 85
Vol 2 Table 5.6.3 Shad Thames Pumping Station - programme dates .................... 87
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List of abbreviations
AADT Annual Average Daily Traffic
ACE Arts Culture and Entertainment
AM MorningAOD Above Ordnance Datum
APZ Archaeological Priority Zone
AQEG Air Quality Expert Group
AQMA Air Quality Management Area
AQO Air Quality Objective
ARS Artificial Recharge Scheme
ASR Aquifer Storage and Recovery
ASSI Area of Special Scientific Interest
ATC Automated Traffic Counter
ATD Above Tunnel Datum (defined at ~100m AOD)
AURN Automatic Urban and Rural Network
BAP Biodiversity Action Plan
BGS British Geological Survey
BMWP Biological Monitoring Working Party
BOD Biochemical Oxygen DemandBPIP Building Profile Input Programme
BPM Best Practicable Means
BS British Standard
CABE Commission for Architecture and the Built Environment
CAMS Catchment Abstraction Management Strategy
CCI Community Conservation Index
CCSS Community Consultation Strategy
CCTV Closed Circuit Television
CDA Critical Drainage Area
CEMP Construction Environment Management Programmes
CIRIA Construction Industry Research and Information Association
CLR Contaminated Land Report
CoCP Code of Construction Practice
CoPA Control of Pollution Act
CROW Countryside and Rights of WayCSO Combined Sewer Overflow
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dB Decibel
dB LAeq,T a equivalent continuous A-weighted sound pressure level havingthe same energy as a fluctuating sound over a specified timeperiod T
DCMS Department for Culture, Media and SportDCO Development Consent Order
DCLG Department for Communities and Local Government
DCMS Department for Culture media and Sport
Defra Department of the Environment, Food and Rural Affairs
DfT Department for Transport
DMP Development Management Plan
DMPD Development Management Policies Document
DMRB Design Manual for Roads and Bridges
DO Dissolved Oxygen
DPD Development Plan Document
DTM Digital Terrain Mapping
EA Environment Agency
EC European Commission
EcIA Ecological Impact Assessment
eVDV Estimated Vibration Dose ValueEEA European Economic Area
EFRA Environment Food and Rural Affairs Committee
EH English Heritage
EHO Environmental Health Officer
EIA Environmental Impact Assessment
EMEP European Monitoring and Evaluation Programme
EN English Nature
EPA Environment Protection Agency
EPB Earth Pressure Balance
EPBM Earth Pressure Balance Machine
EqIA Equality Impact Assessment
EQS Environmental Quality Standard
ES Environmental Statement
EU European Union
FAQ Frequently Asked QuestionsFIDOR Frequency, Intensity, Duration, Offensiveness, Receptor
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FRA Flood Risk Assessment
GARDIT General Aquifer Research Development and Investigation Team
GI Ground Investigation
GiGL Greenspace Information for Greater London
GIS Geographical Information System
GLA Greater London Authority
GLHER Greater London Historic Environment Record
GQA General Quality Assessment (EA water quality classification)
GSHP Ground Source Heat Pump
GWB Groundwater Body: distinct volume of groundwater within anaquifer or aquifers
GWMU Ground Water Management UnitH2S Hydrogen sulphide
ha hectares
HA Highways Authority
HDV Heavy Duty Vehicle
HEA Historic Environmental Assessment
HER Historic Environment Record
HGV Heavy Goods Vehicle
HIA Health Impact AssessmentHIAB Hydrauliska Industri AB Company
HPA Health Protection Agency
HQ Headquarter
HRA Habitats Regulations Assessment
HTC Hammersmith Town Centre
HWR Hazardous Waste Regulations (2005)
IEEM Institute of Ecology and Environmental Management
IEMA Institute of Environmental Management and Assessment
IMD Index of Multiple Deprivation
IPC Infrastructure Planning Commission
Iron Age 600 BC AD 43
JNCC Joint Nature Conservation Committee
kg kilograms
km kilometre
kVA kilo watt amperes
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kW kilowatt
l/d litres per day
l/s litres per second
LA Local Authority
LAARC London Archaeological Archive and Research Centre
LAQM Local Air Quality Management
LAQN London Air Quality Network
LB London Borough
LBAP Local Biodiversity Action Plan
LDF Local Development Framework
LGV Light Goods Vehicle
LHA Local Highway AuthorityLMB Lambeth Mottled Beds
LNR Local Nature Reserve
loWR List of Wastes Regulations 2005
LSB Lower Shelly Beds
LtB Laminated Beds
LTI London Tideway Improvements
LTT London Tideway Tunnels
LUL London Underground Limited
LVMF London View Management Framework
m metre
m AOD metres above Ordinance Datum (see AOD)
m ATD metres above temporary datum, (see ATD)
m/s metres per second
MAGIC Multi-Agency Geographic Information for the Countryside
Mbgl Metres below ground levelMEICA Mechanical Electrical Instrumentation Controls Automation
Ml/d Megalitres per day (million litres per day)
MoD Ministry of Defence
MOL Metropolitan Open Land
MOLA Museum of London Archaeology
NE Natural England
NESR North East Storm Relief
NCR National Cycle Route
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NGR National Grid Reference
NMR National Monuments Record
NNR National Nature Reserve
NO 2 Nitrogen dioxide
NOx Oxides of nitrogen
NPPF National Planning Policy Framework
NPS National Policy Statement
NRMM Non Road Mobile Machinery
NSIP Nationally Significant Infrastructure Project
NSRA National Small-bore Rifle Association
NTS Non Technical Summary
OCU Odour Control UnitOfwat The Water Services Regulations Authority
OS Ordnance Survey
OU E European Odour Unit
PAH Polycyclic aromatic hydrocarbons
PCB Polychlorinated Biphenyl
PEI Preliminary Environmental Information
PEIR Preliminary Environmental Information Report
PEL Probable Effect Levels
PICP Pollution Incident Control Plan
PIP Project Information Paper
PLA Port of London Authority
PM Afternoon
PM 10 Particles on the order of ~10 micrometers or less
PPC Pollution Prevention and Control
PPE Personal Protective EquipmentPPG Pollution Prevention Guidance
PPS Planning Policy Statement
PPV Peak Particle Velocity
PRoW Public Rights of Way
PS Pumping Station
pSPA Potential Special Protected Area
PWS Public Water Supply
RAMS Risk Assessment Method Statement
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RAMSAR The Convention on Wetlands of International Importance
RB Royal Borough
RBKC Royal Borough of Kensington and Chelsea
RBMP River Basin Management Plans
RDB Red Data Book
RHS Royal Horticultural Society
RPG Regional Planning Guidance
RSPB Royal Society for the Protection of Birds
RDB Red data book
RTC Real Time Control
RTD River Terrace Deposits
SA Sustainability AppraisalSAC Special Area of Conservation
SAM Scheduled Ancient Monument. More commonly referred to asScheduled Monument
SCI Statement of Community Involvement
SCL Sprayed Concrete Lining
SFRA Strategic Flood Risk Assessment
SI Statutory Instrument
SINC Site of Importance for Nature ConservationSMI Site of Metropolitan Importance
SNCI Site Nature Conservation Importance
SO 2 Sulphur dioxide
SoCC Statement of Community Consultation
SPA Special Protection Area
SPD Supplementary Planning Document
S-P-R Source-pathway-receptor
SPZ Source Protection Zone
SR Storm Relief
SRN Strategic Road Network
SSR Site Suitability Report
SSSI Site of Special Scientific Interest
STW Sewage Treatment Works
SUDS Sustainable (Urban) Drainage Systems
SWMP waste - Site Waste Management Plan
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SWMP water Surface Water Management Plan
t tonne
TA Transport Assessment
TAS Thames Archaeological Survey
TBC To be confirmed
TBM Tunnel Boring Machine
TDP Thames Discovery Programme
TEBP Thames Estuary Benthic Programme
TEL Threshold Effect Levels
TfL Transport for London
TFRM Tideway Fish Risk Model
TH Tower HamletsTLRN Transport for London Road Network
Tpa tonnes per annum
TPO Tree Preservation Order
TT Thames Tunnel
TTQI Thames Tideway Quality Improvements
TTSS Thames Tideway Strategic Study 2005
TWU Thames Water Utilities
UDP Unitary Development Plan
UK United Kingdom
UKHO United Kingdom Hydrographic Office
UMB Upper Mottled Beds
UPN Upnor Formation
UWWTD Urban Waste Water Treatment Directive
UWWTR Urban Waste Water Treatment Regulations
UXO Unexploded OrdnanceVDV Vibration Dose Value
VNEB OA Vauxhall Nine Elms Battersea Opportunity Area
WCA Wildlife and Countryside Act
WEEE Waste Electrical and Electronic Equipment Directive
WFD Water Framework Directive
WIA Water Industry Act 1991
WRAP Waste Resources Action Programme
WSI Written Scheme of Investigation
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WWT Wildfowl and Wetlands Trust
ZTV Zone of Theoretical Visibility
ZVI Zone of Visual Influence
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Volume 2: Proposed development Section 1: Introduction
Page 1 Preliminary environmental informationreport
1 Introduction1.1.1 This volume provides details of background documents related to the
project, and describes the need for the project. It summarises theextensive background work and research that has already been
undertaken, the Government decision in 2007 to request that ThamesWater urgently proceed with a tunnel solution, and the work done sinceMarch 2007 to verify and update the Thames Tideway Strategy Study(TTSS). Information on the national, regional and local planning context isalso provided.
1.1.2 Part 1, Schedule 4, 2009 Environmental Impact Assessment (EIA)requires that the preliminary environmental information includes adescription of the development. This volume describes the overall phasetwo preferred scheme (the preferred scheme) for the project which is thesubject of phase two consultation. This is the project that is beingenvironmentally assessed in this report.
1.1.3 The plans illustrating the limit of land to be acquired or used (PEIR LLAU)were necessarily provided at a point in time for preliminary environmentalassessment. The draft LLAU lines in some other phase two consultation(eg, Book of plans, and the site information papers) material reflects latestdesign development.
1.1.4 The slight differences mentioned above do not have an effect on theassessment set out in this report.
1.1.5 The permanent works plans were also necessarily provided at a point intime for preliminary environmental assessment, and the permanent works
in other phase two consultation material (eg, Book of plans, and siteinformation papers) reflect latest design development.
1.1.6 Given the preliminary nature of this report, more detailed schemeinformation, including design plans and landscaping plans, will also bepresented and assessed in the ES.
1.1.7 The project description in Section 6 provides information on:
a. main tunnel route
b. main tunnel
c. connection tunnels
d. drive strategy for the tunnels
e. tunnel sites
f. CSO sites
g. construction logistics
h. Code of Construction Practice Part A
i. operational logistics
j. other ancillary works.
1.1.8 Further more detailed information on the proposed development at theconstruction sites is included in Volumes 7 to 28.
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2 Need for the project
2.1 Introduction2.1.1 A full description of the need for the project is provided in the Needs
Report, which is available at:
http://files.thamestunnelconsultation.co.uk/files/thamestunnel/1-100-RG-PNC-00000-900007%20Needs%20Report.pdf
2.1.2 Volume 3, which provides information on strategic and projectalternatives, should be read in conjunction with the following projectneed information.
2.2 Background2.2.1 Substantial portions of Londons sewerage network were built on the
combined principle, whereby a single set of sewers convey foul
sewage and rainwater runoff to sewage treatment works (STWs) fortreatment, prior to discharge to the Thames Tideway. It is normalpractice for combined sewer systems to incorporate overflows in thesystem, known as combined sewer overflows (CSOs). CSOs allowexcess storm flows following rainfall to discharge directly to a waterbody to reduce flood risk to land and properties. This is the case withmuch of the London sewer system which, to alleviate flooding, has ofnecessity been extended over the years and now incorporates 57 CSOswhich discharge to the Thames Tideway and lower River Lee.
2.2.2 The impact of these discharges only began to be appreciated in the late1970s when general improvements to sewage treatment improved thebackground water quality to the point where fish populations were ableto re-establish. Operation of these overflows under certain conditions,particularly summer conditions of low river flows and high temperatures,could result in localised deoxygenation and fish deaths.
2.2.3 Recognising the causes and impacts of these episodes of poor waterquality the Thames Tideway has been the subject of the many studiesover a considerable period of time in relation to increasingenvironmental expectations as well as obligations arising from theinterpretation of successive European Directives. Nonetheless, it wasclear that a major study would be required and this was endorsed in
2000, leading to the establishment of the Thames Tideway StrategicStudy (TTSS).
2.2.4 The Steering Group of the TTSS was assembled in early 2001 to:
a. co-ordinate the study
b. to assess the environmental impact of intermittent discharges ofcombined storm and foul sewage on the Thames Tideway
c. to identify objectives for improvement
d. to propose potential solutions, having regard to benefits and costs.
2.2.5 Thames Water, the EA, Department of Food and Rural Affairs (Defra)and the Greater London Authority (GLA) were represented on the
http://files.thamestunnelconsultation.co.uk/files/thamestunnel/1-100-RG-PNC-00000-900007%20Needs%20Report.pdfhttp://files.thamestunnelconsultation.co.uk/files/thamestunnel/1-100-RG-PNC-00000-900007%20Needs%20Report.pdfhttp://files.thamestunnelconsultation.co.uk/files/thamestunnel/1-100-RG-PNC-00000-900007%20Needs%20Report.pdfhttp://files.thamestunnelconsultation.co.uk/files/thamestunnel/1-100-RG-PNC-00000-900007%20Needs%20Report.pdfhttp://files.thamestunnelconsultation.co.uk/files/thamestunnel/1-100-RG-PNC-00000-900007%20Needs%20Report.pdf8/3/2019 PEIR Main Report Vol2-Proposed-Development
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Steering Group under the independent chairmanship of Professor ChrisBinnie. The Water Services Regulation Authority (Ofwat) maintained anobserver status. The Steering Group was supported by three workinggroups focussed respectively on:
a. objectives,
b. cost-benefits
c. solutions.
2.2.6 As part of the TTSS the EA evaluated the 57 CSOs by considering thevolume and frequency of the discharges, as well as assessing theirimpact on river water quality and ecology. These were then categorisedand a total of 36 CSOs were identified as being unsatisfactory andtherefore requiring control. Of these, 34 discharge directly into theRiver Thames, and the other two into the River Lee. The remaining 21CSOs were assessed by the EA as not requiring any action to be taken.
Of the two unsatisfactory CSOs discharging into the River Lee one willbe addressed by the provision, under a separate scheme, of a 7kmlong, 7.2m diameter storage tunnel from Abbey Mills Pumping Station toBeckton STW. This is referred to as the Lee Tunnel. A localimprovement solution is adequate for the other CSO.
2.2.7 West of Acton there are no significant CSOs discharging to the tidalRiver Thames from the Beckton and Crossness catchments. Themajority of the pollution in the Richmond area of the River Thamesoriginates from the CSOs downstream and reaches the area on theincoming tide. While the catchments served by Beckton and CrossnessSTW to the east have a substantial proportion of combined sewers, thearea in the west of London that drains to Mogden STW contains mostlyseparate sewers for rainwater and sewage. As part of Thames WatersLondon Tideway Improvements programme significant works are underway at the Mogden STW to increase the capacity of the works and soreduce the frequency of overflow from the storm water storage tanks.Consequently there is no water quality justification, nor legislativedriver, to extend the proposed tunnel west of Acton.
2.2.8 Following on from the TTSS and an independent review by JacobsBabtie, further study by Thames Water concluded that, in conjunctionwith the Thames Tideway Quality Improvements and the Lee Tunnelschemes, a single tunnel option, described as the Thames TunnelOption 1c, was the preferred solution satisfying both UK policyframeworks and statutory requirements, including Europeanrequirements, in a phased programme of works. The study culminatedwith a policy decision by the responsible Minister, in support of a full-length storage tunnel.
2.2.9 The draft Waste Water National Policy Statement (NPS) specificallycites the Thames Tunnel project, and sets out the issues to beaddressed for consideration of the application by the IPC or itssuccessor.
2.2.10 The London Plan 2011 supports the project at policy 5.14, as does theMayors Draft Water Strategy 2009 (Proposal 10). In addition, a
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number of London authority local development framework corestrategies also support the project in principle, in accordance with policy5.14 (E) of the London Plan 2011.
2.3 Legislative requirements
2.3.1 The UK Government is required to meet the requirements of the UrbanWaste Water Treatment Directive (UWWTD) and the Water FrameworkDirective (WFD). Thames Water must meet the requirements of therelated UK Urban Waste Water Treatment Regulations (UWWTR) 1994,in respect of collection and treatment of sewage within its area, and therequirements of the Water Environment (WFD) (England and Wales)Regulations, 2003 in respect of aiming to reach good chemical andecological status in inland and coastal waters by 2015.
2.3.2 The impact of the intermittent CSO discharges during wet weather isdependent on river conditions, but it can adversely affect the water
quality and amenity of the tidal River Thames in three main ways:a. introducing sewage derived solid material into the river that can give
rise to unsightly and offensive conditions both in the river and onthe foreshore
b. causing a fall in the amount of dissolved oxygen (DO) in the river,which can drop sufficiently low to result in fish death, and othersevere effects on the aquatic ecosystem
c. introducing pathogenic organisms into the river, which increases thehealth risks to river users.
2.3.3 The UWWTD has the overall aim of protecting the environment fromthe adverse effects of urban wastewater discharges and includes thefollowing requirements:
a. The design, construction and maintenance of collecting systemsshall be undertaken in accordance with the best technicalknowledge not entailing excessive costs, notably regarding volumeand characteristics of urban waste water; prevention of leaks; andlimitation of pollution of receiving waters due to storm wateroverflows. (Annex 1 A).
b. Given that it is not possible in practice to construct collecting
systems and treatment plants in a way such that all waste watercan be treated during situations such as unusually heavy rainfall,Member States shall decide on measures to limit pollution fromstorm water overflows. (Footnote to Annex 1(A)).
c. Urban waste water entering collecting systems shall beforedischarge be subject to secondary treatment or an equivalenttreatment. (Article 4(1)).
d. Urban waste water treatment plants are designed, constructed,operated and maintained to ensure sufficient performance under allnormal local climatic conditions. (Article 10).
2.3.4 The UWWTD recognises that storm overflows will occur undersituations such as unusually heavy rainfall.
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2.3.5 Another consideration is the WFD, which requires surface waters toachieve and maintain good status or good ecological potential in thecases of designated heavily modified water bodies such as the tidalRiver Thames.
2.3.6 In 2004 the European Commission (EC) instigated infractionproceedings against the UK in relation to the CSO discharges to theThames Tideway alleging that the UK was in breach of the UWWTD.The case is now before the European Court with a hearing expectedaround December 2011, and a decision anticipated next summer (ECPress Release IP/09/1488, 8 October, 2009).
2.4 Government response2.4.1 On 27 July 2006, Ian Pearson (then Minister of State for Climate
Change and the Environment) instructed Thames Water to evaluate twoprincipal tunnel options to tackle Londons CSO discharges. This work
culminated in the report entitled Tackling London's Sewer Overflows -Thames Tideway Tunnel and Treatment - Option Development:Summary Report, which recommended that a tunnel solution beadopted.
2.4.2 Subsequently on 22 March 2007 the Minister announced the UKGovernments decision to support the development and implementationof the Thames Tideway Tunnel Storage and Treatment initiative. ARegulatory Impact Assessment was also issued in March 2007.
2.4.3 In a written statement to Parliament on 1 March 2010 the thenSecretary of State for Environment Food and Rural Affairs Committee
(EFRA) (Hilary Benn) announced that he was minded to directapplications for the project to the Infrastructure Planning Commission(IPC). In doing so he set out the case for the project to be a project ofnational significance which, if not implemented, could causereputational risk to the UK. The Secretary of State commented that theurgency of the works is increased by the infraction proceedings beingpursued against the UK by the EC for an alleged breach of theUWWTD.
2.4.4 The succeeding Environment Secretary, Caroline Spelman, issued awritten ministerial statement on 7 September 2010 confirming theCoalition Governments support for the construction of the project anddeclaring that a Thames Tunnel continues to offer (by far) the lowestcost solution to the problem and I believe Thames Water shouldcontinue to press forward with this project working with Ofwat, the EAand Defra on the regulatory, commercial and planning processes.
2.4.5 Further more detailed information on project need is included in theThames Tunnel Needs Report, Thames Water, summer 2010, andassociated Appendices, available at:
http://files.thamestunnelconsultation.co.uk/files/thamestunnel/1-100-RG-PNC-00000-900007%20Needs%20Report.pdf
2.4.6 The draft Waste Water National Policy Statement (NPS) A frameworkdocument for planning decisions on nationally significant wastewater
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infrastructure, Defra, 16 November, 2010 (draft NPS) also addressesproject need. It is available at:
http://archive.defra.gov.uk/corporate/consult/waste-water/101116-wastewaterpolicy-condoc-annex1.pdf
2.4.7 Section 4.2 of the draft NPS notes that the national need for theThames Tunnel project has been demonstrated, and that appropriatestrategic alternatives have been considered and ruled out.
2.4.8 On 13 July 2011 the Government began consultation on a draft orderunder Section 14(3) of the Planning Act 2008, the effect of which wouldbe to designate the project as an NSIP.
2.5 Water quality impacts2.5.1 Discharges from CSOs contain a mixture of foul sewage, groundwater
infiltration and stormwater runoff, and contain pollutants such as
suspended and colloidal solids and volatile organic matter thatcontribute significantly to the organic and chemical oxygen demand inthe river. These result in oxygen depletion and nutrient enrichment ofthe river through London. These conditions are most prevalent duringsummer months when temperatures are higher and oxygen in the riveris more subject to depletion.
2.5.2 Water quality is influenced by physical, chemical and biologicalconditions and is commonly compared to a set of standards againstwhich compliance is assessed. In England and Wales, the EA is thecompetent authority for quality monitoring. The following parametersare among the most useful and important in assessing quality:
a. Biochemical oxygen demand (BOD) - a measure of the amount ofbiodegradable organic matter in water. It is expressed as thenumber of milligrams of oxygen required by micro-organisms tooxidise biodegradable organic matter in one litre of water. As theBOD of a water body increases, so does the demand for oxygen,which causes a subsequent depletion in the DO concentration tothe detriment of water quality.
b. Total ammonia a compound of nitrogen and hydrogen which, athigh concentrations, is toxic to freshwater organisms. It is alsooxidised by certain bacteria in water causing a depletion of DO.The measurement of ammonia and other inorganic nitrogencompounds is usually referenced to the nitrogen and henceammonia is often referred to as ammoniacal nitrogen.
c. Un-ionised ammonia - a form of ammonia that arises underconditions of high temperature and/or pH (alkaline conditions). Thisform of ammonia is more toxic to freshwater organisms than otherforms of ammonia.
d. DO the amount of oxygen dissolved in water expressed asmilligrams of oxygen dissolved in one litre of water. It is influencedby temperature, atmospheric pressure, re-aeration, photosynthesisand the decay of pollutants (as indicated inter alia by ammonia and
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BOD levels). DO concentration decreases with rising temperatureand low DO concentrations can result in fish kills.
e. Nitrogen and phosphorus these are commonly referred to asnutrients. High concentrations can give rise to eutrophication, thecondition where nutrient enrichment supports dense plantpopulations the decomposition of which kills aquatic life by reducingDO concentrations.
2.5.3 In England and Wales, there are water quality standards that should bemet in order to maintain water quality. Whilst those for freshwaters arewell-established, and are in many instances statutory, those forestuaries are historically less well-developed. For this reason the TTSSdeveloped a suite of water quality standards applicable to the ThamesEstuary. Water quality is influenced by a number of sources, which areoutlined in further detail below:
a. Continuous discharges typically continuous discharges come fromtreated effluent from STW, and the quality of the final effluentdepends on the nature of the STW. Specifically the BOD, ammoniaand phosphate in final effluent are considered to assess the impacton water quality in the receiving watercourse.
b. Intermittent discharges this is the discharge of untreated sewageinto a watercourse during times of high flow in the sewer system,typically from CSOs or storm tanks at STWs. As the discharges areuntreated (although perhaps screened), they may discharge highlevels of pollutants into a watercourse which can cause detrimentalimpacts on water quality, in particular a depletion of DO.
c. Diffuse pollution pollution from diffuse sources can include, forexample, agricultural runoff, highway runoff, or runoff fromcontaminated land. Frequently diffuse runoff enters a watercoursewithout being treated and can add significant pollutant to awatercourse.
Influences on water quality in the Thames Tideway
2.5.4 Prior to any improvements affecting water quality in the ThamesTideway, modelling indicated significant water quality impacts on theThames Tideway due to a combination of continuous and intermittent
discharges. Continuous discharges from the five STWs in the ThamesTideway have been shown to have a significant impact on water qualityand resulted in the development of the Thames Tideway QuallityImprovement programme. There are significant intermittent dischargesinto the Thames Tideway from storm tanks at the STWs and CSO spills.Water quality modelling clearly demonstrated that the pollutant loadfrom both continuous and intermittent discharges caused a fall in DOconcentrations that could result in fish mortality. Summer storms inparticular have the capacity for an even greater impact, due to low riverflows resulting in less dilution of the overflows.
2.5.5 Furthermore, the River Thames catchment does not generate largenatural river flows and these are further reduced by abstractions fromthe River Thames upstream of Teddington for use as a potable water
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supply for London. The Thames Tideway does not therefore receivelarge flows of freshwater from upstream to provide dilution andprotection from pollution. As a consequence, there is a very slow netseaward movement of flow causing water to take up to three months totravel along the estuary from Teddington to Southend.
2.5.6 The slow seaward movement of freshwater makes the upper andmiddle reaches of the Thames Tideway particularly vulnerable topollution. The tidal effect moves water up to 15km up and down theRiver Thames on each flood and ebb tide, but on aggregate as little ashalf a kilometre per day towards the sea. During larger rainfall events,this can create slicks of polluted water and solid material (known assewage derived litter) to be washed onto the foreshore during the ebbtide.
2.6 The long term effect of doing nothing
2.6.1 The projected spill volumes and spill frequencies for the baselineconditions for the Thames Tunnel (which is with the Thames TidewayQuality Improvements applied to the STWs, and the Lee Tunnel inplace), and with population projected to 2021, have been estimated. Inessence, these are the conditions that are estimated for 2021 andremain if no further schemes are commissioned and the effects due to
population growth or climate change are not considered. With abaseline total annual CSO discharge to the Thames Tideway of about18 million m 3 and the annual number of spills of up to around 50 timesin a typical year, this will still not be a sufficient level of CSO control tomeet the UWWTD. Unless the Thames Tunnel project proceeds the
UK Government would continue to be subject to the imposition offinancial penalties if suitable action were not taken.
2.6.2 It is not possible to make a reasonable estimate of the size of any finesthat might be imposed in relation to the infraction proceedings againstthe UK government. However, previous cases suggest that fines leviedby the Commission will be significant, as the sole purpose is to ensurethat Member States comply. To this end, the level of the fine is usuallyscaled upwards, based on the Member States ability to pay, to a pointwhere it is no longer economically viable to do anything other thancomply with the legislation.
2.6.3 In terms of the EC, a Reasoned Opinion (European Commission, 10April, 2006) argues that the UK is failing to fully implement the Directive.There are extant infraction proceedings in respect of insufficientcollecting systems and treatment processes. These proceedings arebeing partly addressed by the improvements and extensions at theLondon Tideway sewage treatment plants, the construction of the LeeTunnel and the plans for the Thames Tunnel. The UK is currentlyconsidered non-compliant, although it is believed that the ThamesWater action plan for implementation of the Thames Tideway schemes(including the Thames Tunnel) would satisfy the Commission.
2.6.4 However, the EC announced in a press release dated 8 October 2009(EC Press Release IP/09/1488), that it has decided to continue with the
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legal process and take the UK to the European Court of Justice on thegrounds that urban wastewater collecting systems and treatmentfacilities in London do not comply with European Union (EU) legislation.This is because it considers that the wastewater collecting system inLondon is being allowed to spill untreated wastewaters from CSOs too
frequently and in excessive quantities.2.6.5 With the effects of future population changes and climate change (as
projected), even if modified by changing patterns in water usage, thedoing nothing approach is likely to mean the increased risk of morefrequent overflows, more frequent fish kills, continued increased healthrisks to recreational users, worse litter blight, and adverse impacts onthe attractiveness of the water frontage.
2.6.6 Climate change can be considered to have two principal impacts on theThames Tideway:
a. On the operation of the sewer system although the predictedreduction in summer rainfall is now not as significant as originallythought, drier periods could cause an increase in pollutant build upwhich could increase the impacts of the first flush in any overflowfrom the tunnel. Furthermore, wetter winters could lead to moreoverflows during winter events.
b. On water quality processes in the Thames Tideway water qualitymodelling has demonstrated that increases in river watertemperatures lead to DO depletion due to lower DO saturation andfaster reaction rates. Warmer winter temperatures in conjunctionwith wetter winters could lead to higher overflows from the sewersystem and an associated impact on water quality, although theimpact of these may be moderated by higher flows.
2.6.7 To support the Lee Tunnel and Beckton STW expansion environmentalstudies further water quality modelling was undertaken in March 2008.The water quality assessment aimed to assess the effectiveness of theLee Tunnel and STW improvements in protecting DO levels in theThames Tideway and the River Lee for the immediate and long termsituations. The modelling illustrated that with preceding eventsincluded, the Lee Tunnel and STW improvements (the baselineconditions) would result in improved DO levels in the Thames Tideway,
but would not result in compliance against the interim DO standardsderived as part of the TTSS.
2.6.8 Thus the conclusions of the water quality assessment are that thecurrent baseline conditions (ie, those conditions including the LeeTunnel and London Tideway Improvements) are insufficient to:
a. meet water quality objectives
b. adapt to the impacts of population growth and climate change.
2.7 Conclusion on need
2.7.1 The need for the Thames Tunnel arises from the objective of the EUUWWTD; to protect the environment from the adverse impacts of
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insufficiently treated wastewater discharges. Wastewater collectingsystems in London, in the opinion of the EC, are being allowed to spilluntreated wastewaters from CSOs too frequently and in excessivequantities. The Directive, and related UK legislation, accepts thatcollecting systems and treatment plants may spill water in certain
situations, such as emergency shutdowns or unusually heavy rainfall,but in the case of London, the spills are considered by the Commissionto be excessive and go beyond what the conditions the legislationprovides for.
2.7.2 The EC is taking infraction proceedings because it considers that thecurrent situation of high spill frequencies and large discharge volumesis in breach of the EU UWWTD. The spills also stand to cause breachof the UK UWWTR and to cause the River Thames to be non-compliantwith the objectives of the WFD.
2.7.3 Wastewater discharges affect the environment in three main ways,
which have been considered in developing the specific objectives forthe project, namely:
a. adverse environmental impacts on the river ecosystems and on fishspecies in particular
b. unacceptable aesthetic issues
c. elevated health risks for recreational users of the Thames.
2.7.4 Should nothing be done to address the current situation, with continuingpopulation growth, incremental changes to impermeable areas andprojected increases in the intensity of rainfall, the risk of greater spillage
to the river, with associated adverse environmental impacts, willincrease.
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3 Background documents
3.1 Introduction3.1.1 A considerable amount of background work has been undertaken in
developing the Thames Tunnel project to date.
3.1.2 The following provides information on the Thames Water documents thatare available on the consultation webpage for the Thames Tunnel andhave been important in developing and consulting on the project to date.The consultation webpage is available at:
http://www.thamestunnelconsultation.co.uk
3.2 Strategic documents3.2.1 The following documents are available on the consultation website:
a. Thames Tideway Strategic Study Report, February, 2005: This reportwas undertaken to assess the environmental impact of intermittentdischarges of storm sewage on the Thames Tideway, to identifyobjectives for improvement and to propose potential solutions, havingregard to costs and benefits.
b. Thames Tideway Strategic Study Supplementary Report, November,2005: This report comprises further investigation of the proposed longterm tunnel solution and of alternative measures, including temporaryor interim works and some smaller scale tunnel and/or treatmentoptions.
c. Thames Tunnel Site Selection Methodology Paper, May, 2009: Thispaper provides information about the background and the engineeringrequirements of the Thames Tunnel project.
1.1.1 The following strategic documents are not on the Thames Tunnelconsultation webpage:
a. Ofwat Independent review to assess whether there are EconomicPartial Solutions to Problems caused by Intermittent Storm Dischargesto the Thames Tideway Phase 1, Final Report, February 2006, OfwatRef: PROC/01/0021 (note: only available at
d. Regulatory Impact Assessment 2007 in which the conclusions of a,above, were rejected. This document is available at:
http://www.thameswater.co.uk/cps/rde/xbcr/corp/ofwat-independant-
review.pdf ).
http://archive.defra.gov.uk/corporate/consult/waste-water/101116-wastewaterpolicy-condoc-annex2.pdf
e. draft NPS for Waste Water: A framework document for planningdecisions on nationally significant waste water infrastructure, Defra,November 2010 . This document is available at:
http://archive.defra.gov.uk/corporate/consult/waste-water/101116-
wastewaterpolicy-condoc-annex1.pdf )
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3.3 Phase one consultation documents3.3.1 The following documents are available on the consultation website:
a. Thames Tunnel phase one consultation Site Selection BackgroundTechnical Paper, spring 2010: This paper sets out the methods used
for assessing potential sites to support the construction of the ThamesTunnel.
b. Thames Tunnel phase one consultation Community ConsultationStrategy, September 2010; this strategy sets out the intendedapproach and timetable for consulting all those with an interest in theproposed Thames Tunnel.
c. Thames Tunnel phase one consultation Needs Report, summer2010: This report considers the need for the Thames Tunnel takinginto account the Lee Tunnel and the other London TidewayImprovements. The Needs Report included appendices examining thepracticality of SUDS and Sewer Separation as alternatives and alsolooked at the European Experience.
d. Thames Tunnel phase one consultation General Project InformationPapers (PIPs) and Site Information Papers (SIPs): These papersprovide both general and site specific information about the preferredThames Tunnel project that was part of the phase one consultation.
e. Thames Tunnel phase one consultation Project Overview, summer2010: This report provides information on the need for the ThamesTunnel, the development of the preferred solution, and the processesand outcomes of the site selection and route optioneering workundertaken.
3.4 Phase two consultation documents3.4.1 The Guide to phase two consultation provides an overview of all of the
documents available.
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4 Strategic planning context
4.1 Introduction4.1.1 On the basis that the project will become an NSIP, Thames Water will
need to submit an applicationto the IPC, or its successor, and will alsoneed to address the policies in the draft, or final, version of the WasteWater NPS (whichever is current at the time of the application).
4.1.2 Thames Water will also be considering the regional (Mayor of London) andlocal planning policies (local authorities). A full assessment of thesepolicies will be provided in the Planning Statement that will accompany theapplication.
4.1.3 The following provides details on the national, regional and local relevantto the Thames Tunnels project.
4.2 National planning context4.2.1 The draft NPS for waste water was issued for consultation in November
2010. The IPC or its successor body is the decision-maker forapplications where an NPS has been designated. Under s104(3) of the2008 Act, an application must be decided in accordance with any relevantNPS unless an exception applies, eg, where the decision results in thebreach of international obligations or where the adverse effects of aproposal outweigh the benefits. Once designated, the waste water NPSwill therefore be an important national planning policy document againstwhich the project will be judged by the IPC (or Secretary of State). Evenin its current draft form, the NPS is a material consideration for
applications.4.2.2 The draft NPS specifically cites the Thames Tunnel project, and sets out
the issues to be addressed for consideration of the application by the IPCor its successor. It should be noted that the EFRA Committee of theHouse of Commons considered the draft NPS and one of itsrecommendations was to remove project specific references from the maintext. However on 5 April 2011 Under Secretary of State for Defra, LordHenley, indicated in the House of Lords that he doubted if this wasappropriate (Column GC299).
4.2.3 Section 5 of the draft NPS considers factors for examination and
determination of applications. Two notable environmental issues relate tothe Habitats Regulations Assessment (HRA) and climate changerequirements.
4.2.4 A project level HRA screening report will be prepared to accompany theapplication to confirm whether the project can be implemented withoutadverse effects upon identified European Sites, as recommended in theThames Tunnel section of the draft NPS.
4.2.5 The draft NPS also advises that the application should set out how theproposal will take account of the projected impacts of climate change. Therelevant requirements are described in Section 5.6 of the draft NPS. Theproject is required to satisfy the decision-maker that the proposals havetaken into account potential impacts using the latest UK Climate
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Projections available at the time the ES was prepared. Appropriatemitigation or adaptation measures need to be identified, which should alsocover the estimated lifetime of the new infrastructure (Volumes 6, and 7 to28 have dedicated sections on approach to mitigation, and environmentaldesign already embedded is provided in the draft CoCP (Appendix A).
4.2.6 Section 6 of the draft NPS deals with generic impacts and in a number ofcases, such as odour, landscape and visual impacts, sets out specificguidance on the content of the ES.
4.2.7 On 13 July 2011 the Government began consultation on a draft orderunder Section 14(3) of the Planning Act 2008, the effect of which (if made)would be to designate the project as an NSIP.
4.2.8 Section 104 (2) of the 2008 Act provides that the IPC, in determining anapplication, must have regard to any NPS that has effect and to any othermatters which it thinks are both important and relevant to its decision.This is likely to include various national planning policies covered inPlanning Policy Statements (PPS) or Planning Policy Guidance (PPG)documents, which are therefore a material consideration. Nationalplanning policies also provide the policy context from which all regionaland local planning policies are designed to flow. These are in the processof being amalgamated into a single National Planning Policy Framework(NPPF), which will supersede the existing PPSs and PPGs. TheGovernment have consulted on a draft NPPF document. If this comes intoeffect prior to the completion of the ES and it replaces existing policyguidance, then the final ES will be updated accordingly where possible.
4.2.9 Another relevant national planning context document for the project isDefras Marine Policy Statement, available at:http://www.defra.gov.uk/environment/marine/protect/planning/
4.2.10 Other national planning documents of relevance include publications bythe Department for Culture Media and Sport (DCMS), Department forCommunities and Local Government (DCLG), Defra, English Heritage,Commission for Architecture and the Built Environment (CABE) (now atthe Design Council), and the EA. The document on Climate ResilientInfrastructure, which set out UK Governments overarching policyobjectives for these areas, also provides important context for the projectand is available at:
http://www.defra.gov.uk/publications/2011/05/09/climate-resilient-infrastructure/
4.2.11 It should also be noted that the Localism Bill is currently before Parliamentand this proposes some significant changes to the planning system.However if passed the Bill is unlikely to come into force until April 2012and there is limited scope for this to impact on the ES.
4.3 Regional planning context4.3.1 At a regional level the London Plan sets out the Mayors spatial planning
framework for London, which aims to promote an attractive, well designedand greener city. The London Plan 2011 was published in July 2011.
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4.3.2 Policy issues affecting the Thames Tunnel include:
a. The Thames Tunnel policy
b. safeguarded wharves
c. energy and sustainability policies.
4.3.3 The London Plan provides support for the Thames Tunnel project throughPolicy 5.14 which states that the The development of the ThamesTideway Sewer Tunnels to address Londons combined sewer overflowsshould be supported in principle, and that relevant Boroughs shouldinclude policies within their LDFs to support the project in principle.
4.3.4 Safeguarded wharves continue to be protected in the London Plan 2011,which affects a number of preferred sites for the project. The Mayorsobjective to make better use of the Thames in its transport strategyunderpins the policy safeguard.
4.3.5 With regard to energy and sustainability issues, the draft Plan aims totackle climate change by reducing Londons carbon dioxide emissions,managing resources more effectively and helping the city to cope with theeffects of a changing climate. This is addressed through polices onoverheating and cooling, encouraging urban greening including the use ofgreen roofs, the management of flood risk, sustainable drainage, waterefficiency and the management of water quality.
4.3.6 Local policies contained in LDFs are required to be in general conformitywith the London Plan.
4.4 Local planning context
Acton Storm Tanks, London Borough of Ealing4.4.1 The Acton Storm Tanks site is situated in the London Borough (LB) of
Ealing, however, the LB of Hammersmith and Fulham administrativeboundary is located to the east of the site along Warple Way. Theplanning context for this site must, therefore, consider the planningpolicies for both Ealing and Hammersmith and Fulham.
4.4.2 The current local statutory development plan for the LB of Ealingcomprises the saved policies from the Ealing Unitary Development Plan (UDP), adopted 2004. The Council is working on its Local Development
Framework (LDF) documents. The policies from the Ealing Development Strategy Submission Version , July 2011, are also a material considerationdue to its advanced stage. The Submission Version was submitted forExamination in Public in July 2011, with adoption scheduled for late 2011.
4.4.3 A summary of the LB of Ealing local planning policies and designationsrelevant to the Acton Storm Thanks site is included in Appendix B.
4.4.4 The current local statutory development plan for the LB of Hammersmithand Fulham comprises the saved policies from the Hammersmith and Fulham UDP , adopted 2003. The Council is working on its LDFdocuments. The policies from the Hammersmith and Fulham Core Strategy Proposed Submission , November 2010, are also a materialconsideration with significant weight due to its advanced stage. The
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Proposed Submission went to Examination in Public in April 2011, withadoption scheduled for late 2011.
4.4.5 Relevant Hammersmith and Fulham local planning policies anddesignations applicable to the site are provided in Appendix B.
4.4.6 Further information is also provided in the site context section in the siteassessment volume for Acton Storm Tanks (Volume 7, Section 2).
Hammersmith Pumping Station, London Borough ofHammersmith and Fulham
4.4.7 The current local statutory development plan for the LB of Hammersmithand Fulham comprises the saved policies from the Hammersmith and Fulham UDP , adopted 2003. The Council is working on its LDFdocuments. The policies from the Hammersmith and Fulham Core Strategy Proposed Submission , November 2010, are also a materialconsideration with significant weight due to its advanced stage. TheProposed Submission went to Examination in Public in April 2011, withadoption scheduled for late 2011.
4.4.8 A summary local planning policies and designations relevant to theHammersmith Pumping Station site is provided in Appendix B.
4.4.9 Further information is also provided in the site context section in the siteassessment volume for Hammersmith Pumping Station (Volume 8,Section 2).
Barn Elms, London Borough of Richmond upon Thames
4.4.10 The Barn Elms site is situated in the LB of Richmond upon Thames,however, the LB of Wandsworth administrative boundary is located alongBeverley Brook to the south of the site. The planning context for this sitemust, therefore, consider the planning policies for both Richmond uponThames and Wandsworth.
4.4.11 The current local statutory development plan for the LB of Richmond uponThames comprises the saved policies from the Richmond upon Thames Core Strategy , adopted April 2009, and the saved policies from theRichmond UDP , adopted 2005. The Council is working on the rest of itsLDF documents. The policies from the Hammersmith and Fulham Development Management Plan (DMP) Publication Version , October2010, are also a material consideration due to its advanced stage. ThePublication Version went to Examination in Public in May 2011, withadoption scheduled for late 2011.
4.4.12 A summary of the LB of Richmond upon Thames local planning policiesand designations relevant to the Barn Elms site is included in Appendix B.
4.4.13 The current local statutory development plan for the LB of Wandsworthcomprises of the Wandsworth Core Strategy , adopted October 2010, andthe saved policed from the Wandsworth UDP, adopted 2003. The Councilis working on the rest of its LDF documents. The policies from theWandsworth Development Management Policies Document Submission Version , May 2011, are also a material consideration due to its advanced
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stage. The Submission Version was submitted for Examination in Publicin May 2011, with adoption scheduled for April 2012.
4.4.14 Relevant Wandsworth local planning policies and designations applicableto the site are provided in Appendix B.
4.4.15 Further information is also provided in the site context section in the siteassessment volume for Barn Elms (Volume 9, Section 2).
Putney Bridge Foreshore, London Borough of Wandsworth4.4.16 The current local statutory development plan for the LB of Wandsworth
comprises of the Wandsworth Core Strategy , adopted October 2010, andthe saved policies from the Wandsworth Unitary Development Plan, adopted 2003. The Council is working on the rest of its LDF documents.The policies from the Wandsworth DMPD and the Site Specific Allocations Document (SSAD) Submission Versions , May 2011, are also a materialconsideration due to their advanced stage. These documents weresubmitted for Examination in Public in May 2011, with adoption scheduledfor April 2012.
4.4.17 A summary of local planning policies and designations relevant to thePutney Bridge Foreshore site is provided in Appendix B.
4.4.18 Further information is also provided in the site context section in the siteassessment volume for Putney Bridge Foreshore (Volume 10, Section 2).
Dormay Street, London Borough of Wandsworth4.4.19 See para. 4.4.16 for general local planning context information on LB of
Wandsworth.
4.4.20 A summary of local planning policies and designations relevant to theDormay Street site is provided in Appendix B.
4.4.21 Further information is also provided in the site context section in the siteassessment volume for Dormay Street (Volume 11, Section 2).
King Georges Park, London Borough of Wandsworth4.4.22 See para. 4.4.16 for general local planning context information for the LB
of Wandsworth.
4.4.23 A summary of local planning policies and designations relevant to the KingGeorges Park site is provided in Appendix B.
4.4.24 Further information is also provided in the site context section in the siteassessment volume for King Georges Park (Volume 12, Section 2).
Carnwath Road Riverside, London Borough ofHammersmith and Fulham
4.4.25 See para. 4.4.7 for general local planning context information for the LB ofHammersmith and Fulham.
4.4.26 A summary of local planning policies and designations relevant to the
Carnwath Road Riverside site is provided in Appendix B.
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4.4.27 Further information is also provided in the site context section in the siteassessment volume for Carnwath Road Riverside (Volume 13, Section 2).
Falconbrook Pumping Station, London Borough ofWandsworth
4.4.28 See para. 4.4.16 for general local planning context information for the LBof Wandsworth.
4.4.29 A summary of local planning policies and designations relevant to theFalconbrook Pumping Station site is provided in Appendix B.
4.4.30 Further information is also provided in the site context section in the siteassessment volume for Falconbrook Pumping Station (Volume 14, Section2).
Cremorne Wharf Depot, Royal Borough of Kensington andChelsea
4.4.31 The current local statutory development plan for the Royal Borough ofKensington and Chelsea comprises the Kensington and Chelsea Core Strategy , adopted December 2010, and the saved policies from theKensington and Chelsea UDP, adopted 2002.
4.4.32 A summary of local planning policies and designations relevant to theCremorne Wharf Depot site is provided in Appendix B.
4.4.33 Further information is also provided in the site context section in the siteassessment volume for Cremorne Wharf Depot (Volume 15, Section 2).
Chelsea Embankment Foreshore, Royal Borough ofKensington and Chelsea
4.4.34 See para. 4.4.31 for general local planning context information for the RBof Kensington and Chelsea.
4.4.35 A summary of local planning policies and designations relevant to theChelsea Embankment Foreshore site is provided in Appendix B.
4.4.36 Further information is also provided in the site context section in the siteassessment volume for Chelsea Embankment Foreshore (Volume 16,Section 2).
Kirtling Street, London Borough of Wandsworth4.4.37 See para. 4.4.16 for general local planning context information on LB of
Wandsworth.
4.4.38 A summary of local planning policies and designations relevant to theKirtling Street site is provided in Appendix B.
4.4.39 Further information is also provided in the site context section in the siteassessment volume for Kirtling Street (Volume 17, Section 2).
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Heathwall Pumping Station, London Borough ofWandsworth
4.4.40 See para. 4.4.16 for general local planning context information on LB ofWandsworth.
4.4.41 A summary of local planning policies and designations relevant to theHeathwall Pumping Station site is provided in Appendix B.
4.4.42 Further information is also provided in the site context section in the siteassessment volume for Heathwall Pumping Station (Volume 18, Section2).
Albert Embankment Foreshore, London Borough ofLambeth
4.4.43 The current local statutory development plan for the LB of Lambethcomprises the Lambeth Core Strategy , adopted January 2011, and savedpolicies from the Lambeth UDP , adopted 2007.
4.4.44 A summary of local planning policies and designations relevant to theAlbert Embankment Foreshore site is provided in Appendix B.
4.4.45 Further information is also provided in the site context section in the siteassessment volume for Albert Embankment Foreshore (Volume 19,Section 2).
Victoria Embankment Foreshore, City of Westminster4.4.46 The current local statutory development plan for the City of Westminster
comprises the City of Westminster Core Strategy , adopted January 2011,and saved policies from the City of Westminster UD P , adopted 2007.
4.4.47 A summary of local planning policies and designations relevant to theVictoria Embankment Foreshore site is provided in Appendix B.
4.4.48 Further information is also provided in the site context section in the siteassessment volume for Victoria Embankment Foreshore (Volume 20,Section 2).
Blackfriars Bridge Foreshore, City of London4.4.49 The current local statutory development plan for the City of London
comprises the saved policies from the City of London UDP , adopted 2002.The Council is working on its LDF documents. The policies from the City of London Core Strategy Submission Version, December 2010, are also amaterial consideration due to its advanced stage.
4.4.50 A summary of local planning policies and designations relevant to theBlackfriars Bridge Foreshore site is provided in Appendix B.
4.4.51 Further information is also provided in the site context section in the siteassessment volume for Blackfriars Bridge Foreshore (Volume 21, Section2).
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Chambers Wharf, London Borough of Southwark4.4.52 The current local statutory development plan for the LB of Southwark
comprises of the Southwark Core Strategy , adopted April 2011, and thesaved policies from the Southwark Plan , LB Southwarks UDP, adopted2007.
4.4.53 A summary of local planning policies and designations relevant to theChambers Wharf site is provided in Appendix B.
4.4.54 Further information is also provided in the site context section in the siteassessment volume for Chambers Wharf (Volume 22, Section 2).
King Edward Memorial Park Foreshore, London Borough ofTower Hamlets
4.4.55 The current local statutory development plan for the LB of Tower Hamletscomprises of the Tower Hamlets Core Strategy, adopted September 2010,
and the saved policies from the Tower Hamlets UDP, adopted 1998, andsaved policies from the interim planning guidance Core Strategy andDevelopment Control Plan, 2007.
4.4.56 A summary of local planning policies and designations relevant to the KingEdward Memorial Park Foreshore site is provided in Appendix B.
4.4.57 Further information is also provided in the site context section in the siteassessment volume for King Edward Memorial Park Foreshore (Volume23, Section 2).
Earl Pumping Station, London Borough of Lewisham
4.4.58 The Earl Pumping Station site is situated in the LB of Lewisham, however,the LB of Southwark administrative boundary is located along the sitesnorthern and western boundaries. The planning context for this site musttherefore consider the planning policies for both Lewisham andSouthwark.
4.4.59 The current local statutory development plan for the LB of Lewishamcomprises the Lewisham Core Strategy, adopted June 2011, and thesaved policies from the Lewisham UDP adopted 2004.
4.4.60 A summary of the LB of Lewisham local planning policies anddesignations relevant to the Earl Pumping Station site is included inAppendix B.
4.4.61 The current local statutory development plan for the LB of Southwarkcomprises the Southwark Core Strategy , adopted April 2011, and thesaved policies from the Southwark Plan , LB of Southwarks UDP, adopted2007.
4.4.62 Relevant Southwark local planning policies and designations applicable tothe site are provided in Appendix B.
4.4.63 Further information is also provided in the site context section in the siteassessment volume for Earl Pumping Station (Volume 24, Section 2).
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Deptford Church Street, London Borough of Lewisham4.4.64 See para. 4.4.59 for general local planning context information on LB of
Lewisham.
4.4.65 A summary of local planning policies and designations relevant to the
Deptford Church Street site is provided in Appendix B.4.4.66 Further information is also provided in the site context section in the site
assessment volume for Deptford Church Street (Volume 25, Section 2).
Greenwich Pumping Station, London Borough ofGreenwich
4.4.67 The current local statutory development plan for the LB of Greenwichcomprises the saved policies from the Greenwich UDP adopted 2006.The Council is working on its LDF documents. .
4.4.68 A summary of local planning policies and designations relevant to theGreenwich Pumping Station site is provided in Appendix B.
4.4.69 Further information is also provided in the site context section in the siteassessment volume for Greenwich Pumping Station (Volume 26, Section2).
Abbey Mills Pumping Station, London Borough of Newham4.4.70 The current local statutory development plan for the LB of Newham
comprises the saved policies from the Newham UDP , adopted 2001.
4.4.71 The Council is working on its LDF documents. The policies from the
Newham Core Strategy Submission Draft , March 2011, are also a materialconsideration due to its advanced stage. The Submission Draft wassubmitted for Examination in Public in March 2011, with adoptionscheduled for mid 2012.
4.4.72 A summary of local planning policies and designations relevant to theAbbey Mills Pumping Station site is provided in Appendix B.
4.4.73 Further information is also provided in the site context section in the siteassessment volume for Abbey Mills Pumping Station (Volume 27, Section2).
Beckton Sewage Treatment Works, London Borough ofNewham
4.4.74 See para. 4.4.70 for general local planning context information on LB ofNewham.
4.4.75 A summary of local planning policies and designations relevant to theBeckton Sewage Treatment Works site is provided in Appendix B.
4.4.76 Further information is also provided in the site context section in the siteassessment volume for Beckton Sewage Treatment Works (Volume 28,Section 2).
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5 Project description
5.1 Introduction5.1.1 This section presents information that describes the proposed Thames
Tunnel development that is the subject of phase two consultation, andcovers:
a. overview of the phase two preferred scheme
b. construction logistics
c. code of construction practice (CoCP)
d. operational logistics
e. construction environmental management and monitoring proposals.
5.1.2 Further information on the tunnel sections of the project is included in theproject-wide assessment (Volume 6).
5.1.3 Further details on the proposed development at specific sites are includedin Volumes 7 to 28.
5.2 Overview of the phase two preferred scheme
Overview5.2.1 The Thames Tunnel comprises a wastewater storage and transfer tunnel
from Acton Storm Tanks to Abbey Mills Pumping Station with connectionto the Lee Tunnel. The Thames Tunnel controls 34 CSOs along theThames Tideway. The project comprises three main elements:
a. works to build and operate the main tunnel that would provide themajority of the storage capacity and enable transfer of untreatedsewage to Beckton STW in east London
b. works to control and intercept untreated sewage from the worstpolluting CSOs and transfer it into the main tunnel
c. connection tunnels would also be required to connect some of theintercepted CSOs to the main tunnel.
5.2.2 During and following storm events, when the sewers are unable to handleextra flow and would otherwise overflow to the river, interception works
would divert CSO discharge flows into the tunnel system for storagebefore transfer for treatment.
5.2.3 CSO flows would be diverted by building a series of structures, known asCSO interception works, to divert the flows from existing sewers into thetunnel system.
5.2.4 The EA has identified 34 unsatisfactory CSOs that the Thames Tunnelproject needs to address. Design development has shown that not all ofthe 34 CSOs would require their own individual CSO interception works inorder for them to be adequately controlled. For some CSOs, it should bepossible to use existing sewers and pumping station operation
modifications to control their overflows at one of the other CSO
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interception works locations. This has the advantage of reducing thenumber of CSO sites required. It is envisaged that there would be:
a. some CSOs that would be directly controlled by being intercepted,which would only deal with the flows from one CSO
b. some CSOs that would be directly controlled by being intercepted,which would also need to deal with the flows from CSOs that wouldnot be directly controlled
c. some CSOs where two connections would be needed: one to interceptthe flows from the CSO and one to divert some of the flows fromanother existing sewer. The flows from some other CSOs would becontrolled as a result of these double connections so that nomodifications would be required at them at all
d. some CSOs that would not be directly controlled through interception,but would be indirectly controlled through modifications to change the
operation of the existing sewerage system, including:i adjustments to existing pumping stations
ii local in-sewer modifications that allow flows to be passed forwardthrough the existing sewer system to the treatment works, or to bepassed to other CSOs that would be intercepted.
5.2.5 Further studies are required to refine the method of flow control for eachCSO, but current findings are that 16 CSOs can be indirectly controlled,reducing the number of CSOs needing to be intercepted from 34 to 18.
5.2.6 The flows from the 18 CSOs which are to be intercepted would be
connected to the main tunnel and forwarded for treatment at Beckton STWvia the Lee Tunnel. The flow control proposals for the 34 unsatisfactoryCSOs are listed in the table below.
Vol 2 Table 5.2.1 Method of flow control for each CSO and CSO sitelocations
Combined seweroverflow Method of overflow control
CSO interceptionconstruction site
Acton Storm Relief Interception Acton Storm Tanks
Stamford Brook StormRelief
Control measures at otherCSOs indirectly controls thisCSO
No site required
North West Storm Relief
Interception and pumpingstation operation changes atHammersmith PumpingStation indirectly controls thisCSO
No site required
Hammersmith PumpingStation
Interception and pumpingstation operation changes
Hammersmith PumpingStation
West Putney Storm Relief Interception Barn ElmsPutney Bridge Interception Putney Bridge Foreshore
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Combined seweroverflow Method of overflow control
CSO interceptionconstruction site
Frogmore Storm Relief Bell Lane Creek
Frogmore Storm Relief Buckhold Rd
Interception
Dormay Street
King Georges Park
Jews Row Wandle ValleyStorm Relief