london wall place 121-123 london wall, ec2 - iema · as london wall place, 121-123 london wall ec2...

London Wall Place 121-123 London Wall, EC2Environmental Statement Non Technical SummaryOctober 2010Prepared by URS

London Wall Place ES Non-Technical Summary

1

1. Introduction

1.1 The Application

Hammerson (Centurion) Limited (the ‘Applicant’) is seeking full planning permission for the demolition of existing buildings and construction of an office-led scheme on the existing St Alphage House tower and podium, to be known as London Wall Place, 121-123 London Wall EC2 (the ‘Development’). Parallel applications for Listed Building Consent and Scheduled Ancient Monument (SAM) Consent are also being made in relation to the works associated with the Grade II Listed St Alphage Church Tower remains, the remains of the London Wall and the alteration and reinstatement of a series of highwalk bridge connections to the Barbican and surrounding area.

The site has an area of approximately 0.725 hectares (ha) and is located within the City of London (CoL). The site is formed by two triangles linked at the remains of St Alphage Church Tower in the centre of the plot, and is bounded by Fore Street and St Alphage Garden to the north, Fore Street Avenue to the east, London Wall to the south, and Wood Street to the west. St Alphage Highwalk bisects the site. The site is also connected to Moorfields Highwalk to the east, Alban Highwalk to the west, Willoughby Highwalk to the north and and Bassishaw Highwalk to the south. Figure 1 shows the location of the site and Figure 2 illustrates the site plan and red line boundary.

Figure 1: Site Location

1.2 The EIA Process

URS Corporation Limited (URS) was commissioned by the Applicant to undertake an Environmental Impact Assessment (EIA) in line with the Town and Country (Environmental Impact Assessment) (England and Wales) Regulations 1999 (as amended). The results of this process are presented within the Environmental Statement (ES) and accompanying technical appendices. This document, known as the Non-Technical Summary (NTS), provides an overview of the findings of the EIA.

The NTS has been prepared for a general audience, including parties potentially affected by the Development. The ES describes the potential impacts of the Development during the demolition and initial site preparation works, the construction phase and on completion and occupation of the Development.

The ES has considered the likely impact of the Development on its neighbours, local environment, the local and regional economy and the wider project area. Beneficial and adverse, short and long-term impacts have also been considered. Mitigation measures to either eliminate or reduce adverse impacts have been incorporated into the project design wherever possible.


2

Figure 2: Site Plan and Red Line Boundary

=

=

=

=

The ES has highlighted the residual impacts, which are those impacts that remain following the incorporation of any identified mitigation measures. The significance of residual impacts has been evaluated with reference to definitive standards, accepted criteria and legislation where available.

Where it has not been possible to quantify impacts, qualitative assessments have been carried out based on professional experience and judgement.

Impacts have been classified as being adverse, negligible or beneficial in significance and either minor, moderate or major in magnitude. Where possible, impacts have also been assigned a geographic scale; for example, Local, District or Regional.

The ES also describes the consultation process undertaken to ensure that the views and concerns of interested parties, and statutory consultees, have been given due consideration in the design process. The ES comprises:

• ES Volume I – Environmental Statement: This document presents the findings of the EIA and is divided into a number of background and technical chapters supported with figures and tabular information for clarity of reading;

• ES Volume II – Townscape, Conservation and Visual Impact Assessment: This document comprises a stand-alone Townscape, Conservation and Visual Assessment accompanied by a set of views and images;

• ES Volume III – Technical Appendices: The Technical Appendices provide detail on the assessments undertaken and information used to inform ES Volume I; and

• ES Non-Technical Summary (NTS): This document.

MN==bñáëíáåÖ=pí=^äéÜ~ÖÉ=eçìëÉ=qçïÉê= ^==pí=^äéÜ~ÖÉ=`ÜìêÅÜ=qçïÉê=oÉã~áåë=

MO==^NL^P=råáí= _==içåÇçå=t~ää=oÉã~áåë=

MP==bñáëíáåÖ=mìÄäáÅ=pí~áê= `==táääçìÖÜÄó=eáÖÜï~äâ=

MQ==bñáëíáåÖ=mìÄäáÅ=iáÑí= a==_~ëëáëÜ~ï=eáÖÜï~äâ=

MR==bñáëíáåÖ=o~ãé= b==jççêÑáÉäÇë=eáÖÜï~äâ=

MS==mä~åíÉÇ=^êÉ~= c=^äÄ~å=eáÖÜï~äâ=


3

2. Scoping and Consultation

The process of consultation is critical to the development of a comprehensive and balanced ES. Views of key statutory and non-statutory consultees serve to focus the environmental studies and to identify specific issues, which require further investigation. Consultation is also an ongoing process, which enables mitigation measures to be incorporated into the project design, thereby limiting adverse impacts and enhancing benefits.

Consultees involved in the evolution of the design and assessment of environmental and socio-economic impacts include:

• City of London (CoL);

• Greater London Authority (GLA);

• English Heritage (EH);

• The Environment Agency (EA);

• Commission for Architecture and the Built Environment (CABE);

• Transport for London (TfL) and London Buses;

• City of London Police;

• London City Airport (LYC);

• Crossrail;

• Local groups, including the Barbican Association (St Alphage Committee) and the City of London Access Group; and

• Landowners and neighbouring occupiers, including Salters’ Hall, Brewers’ Hall, Museum of London, St Giles-without-Cripplegate Church.

In addition to those stakeholders noted above, the Applicant has consulted extensively with local residents. The Statement of Community Involvement provides a description and account of the consultation undertaken by the Applicant with stakeholders.

The ES has also been preceded by a preliminary scoping exercise to determine those environmental aspects that may be significantly affected/impacted by a development, and, as such, should be included in the scope of the EIA. Through Scoping, the potential significance of impacts associated with each environmental aspect becomes more clearly defined, resulting in the identification of a number of priority issues to be addressed in the EIA. A Scoping Report setting out the proposed scope of the EIA was submitted to the CoL on 23 July 2010 and a Scoping Opinion was received from the CoL on 14 October 2010.

3. Planning Policy Context

Section 38(6) of the Planning and Compulsory Purchase Act 2004, requires proposals to be determined in accordance with the Development Plan unless material considerations indicate otherwise. The Development has been assessed against the Development Plan and other relevant planning policy and guidance at national, regional and local policy level.

The Development responds to and takes into account the many different comments and responses received from stakeholders during the pre-application stages, and will, in many ways, regenerate and enhance the site and contribute to the setting of the wider area.

Most importantly, the Development, through the provision of high quality flexible office accommodation, will enhance the CoL as a globally attractive finance and business location and generate capacity to meet current and future office demand, strongly according with the CoL’s Unitary Development Plan (UDP) Policies STRAT 2A and ECON 1 (i.e. promote the City as the world's leading international financial and business centre and encourage office development).

4. Alternatives and Design Evolution

Under the 1999 EIA Regulations (as amended), an ES is required to provide “an outline of the main alternatives studied by the applicant or appellant and an indication of the main reasons for [his] choice, taking into account the environmental effects”. The alternatives analysis is a key part of the EIA process and serves to ensure that environmental considerations are built into the project design at the earliest possible stage.

The EIA has considered the ‘no development’ alternative, the use of ‘alternative sites’ and ‘alternative designs’ in response to consultee comments.

The ‘no development’ option results in a number of undesirable outcomes including the under utilisation of the current site by the existing buildings; concealment of archaeological remains; continued segregation of street and raised pedestrian walkways at the junction between these two urban scales; ongoing repair works to restore and maintain the existing structure; and retention of building stock inappropriate to current and future uses, performance standards and energy demands.

No alternative sites were considered as part of the proposals, as the scheme has been designed as a direct response to the specific site’s potential.


4

The site is formed by two triangles linked at the remains of the Grade II Listed St Alphage Church in the centre of the plot (Figure 3). The existing St Alphage House tower stands 17 storeys (with an additional double height plant enclosure) above a 2 storey podium that extends over the whole site. A series of empty single storey retail and public house units are located at podium level.

The site itself is an important, strategic site in the heart of the CoL. The site lies within an Archaeology Priority Area. A SAM in the form of a surviving section of the London Wall can be found partially located within the application boundary on a northwest to southeast alignment (Figure 4).

Figure 3: St Alphage Church Remains

Figure 4: Existing London Wall Remains

The site is also located immediately adjacent to the Barbican Estate, which itself is Grade II Listed and the CoL’s largest residential area. The site is well served by public transport rail and underground services at Moorgate, St Paul’s, Barbican, Bank and Liverpool Street.

Over the course of each of the design stages, the scheme has developed through consultation and a progression of ideas that have led to its present scale and form. Figures 5 to 7 illustrate the three main approaches to the Development’s footprint and massing that emerged during the concept assessment.

In summary, Option 1 was considered to not engage with London Wall and presented a continuous wall to the Barbican. The approach was found to provide limited permeability with a compromised public space encircled with commercial space. The form did not lend itself to changes in response to constraints.

Figure 5: Option 1 Build to Perimeter with Central Atrium

Option 2 continued the 1950s grain of the existing site and was found to not change the north-south scale between the City and the Barbican. The form does not address London Wall and permeability on plan is not apparent on the street level approach. There was limited opportunity to respond to site constraints from the Barbican.

Figure 6: Option 2 North-South Alignment

The selected east-west alignment of Option 3 responds positively to the site constraints and history while engaging with London Wall, actively responding to the adjacent Barbican Estate and addressing the failings of Option 1 and 2.

Figure 7: Option 3 East-West Alignment


5

Unlike many buildings which have recently been designed tightly for a single particular way of working or service systems, the Development is designed to be both flexible and adaptable.

In summary, the principal restrictions that have informed the massing, quantum of space and external form are both external and internal. The preferred scheme has emerged as the development submitted for planning permission having taken into consideration the following key factors:

External Factors

• Appearance in views (both identified local views and those from neighbouring properties), and respecting the London View Management Framework (LVMF);

• Daylight, sunlight and shadowing impacts;

• Perception and privacy when viewed from within the Barbican Estate;

• Existing and proposed open and public spaces; and

• Relationship to the historic and listed structures that are both within the site and impacted by the proposals.

Internal Factors

• The need to prepare a viable and deliverable scheme that allows the site to be developed and reduce blight;

• Meeting a need for occupiers, by addressing current requirements and allowing adaption and change;

• Providing, in line with CoL policy, the opportunity for large floorplate buildings where possible;

• Testing of all spaces with building service engineers, agents and office space planners;

• Efficient buildings that make optimal use of the site; and

• Providing adaptable and flexible accommodation in accordance with the CoL’s policies on sustainable design principles that allow the buildings to evolve.

The preferred approach was developed through internal and external consultation and testing (Figure 8).

Figure 8: Design Evolution Models within Make’s Studios

=

=

=

=

=

=

=

5. The Proposed Development

The Development has been designed by Make Architects. The proposals involve the demolition of existing structures (but retention of the St Alphage Church remains) and construction of two commercial-led buildings (‘121 London Wall’ (the eastern building) and ‘123 London Wall’ (the western building’)), which address London Wall along with retail units and amenity space.

121 London Wall varies from four storeys to 12 storeys (plus plant floor above street). At it highest point, 121 London Wall is 74.9 metres (m) Above Ordnance Datum (AOD) and comprises office space, with retail and restaurant/café uses at street and highwalk level.

123 London Wall is 16 storeys in height (plus double height plant enclosure above street storey), which equates to 91.37m AOD. 123 London Wall comprises office space (floors 1-16), with retail and restaurant/café space at street and basement level. Additional details are given in Table 1.

Table 1: Proposed Area Schedule by Use

Use Net Internal Area (NIA) (m2)

Gross External Area (GEA) (m2)

Office QRIMVN= STIUNR=

Retail/Restaurant/Café VMR= NIOQR=

Total QTIOMN= SVIMSM=

Note: Total NIA includes 1,205m2 of office lobbies. GEA includes: all levels

(including basement), parking, plant (internal and partially covered external),

back-of-house and lobby areas.

A total of 16 private car parking spaces, 2 disabled spaces and 87 motorcycle spaces located within a single basement. In addition, the proposal includes 1 disabled parking space at street level, storage for 307 bicycles, provided in a combination of ground floor and basement spaces, and a further 30 cycle parking spaces will be provided for short-stay visitors within the landscaped areas around the buildings. The proposals also include the following:

• The creation of an enhanced City garden through connection to and expansion of the existing St Alphage Gardens;

• Improved public access to the remains of St Alphage Church, St Alphage Gardens and the City highwalk from street level;

• Reinstatement of the public highway and increased areas of soft and hard landscaping surrounding and throughout the site; and


6

• Disconnection of the existing highwalk and construction of a new highwalk to reinstate existing links.

Figure 9 demonstrates the mix of uses for the proposed 121 and 123 London Wall buildings, while Figures 10 to13 present renderings of the Development. Figure 9: Proposed Mix of Uses for 121 and 123 London Wall

Figure 10: Proposed Central Public Realm (looking west)

Figure 11: 121 (left) and 123 London Wall (right) Façades

Figure 12: Reflecting Pools within 121 London Wall (left) and Integration of St Alphage Gardens (right)

Figure 13: 121 London Wall (looking from the southwest)

6. Sustainability

The Development has been developed with sustainable design principles at its core. An integrated and holistic approach to design has been adopted, with the sustainability strategy aiming to:

• Match or exceed today’s requirements;

• Anticipate tomorrow’s requirements; and

• Adapt and remain relevant into the future.


7

The Development will meet the objectives of the London Policy Plan 4B.6 Sustainable Design and Construction, outlined in the Mayor of London’s Supplementary Planning Guidance. This document requires that boroughs ensure future developments meet the highest standards of sustainable design and construction.

In doing so, the following energy efficiency measures are incorporated as part of the Development:

• Effective control of electric lighting through the installation of light sensors in combination with efficient luminaries with low power density;

• High efficient condensing boilers;

• High efficiency cooling achieved using cooling towers, absorption chillers driven by District Heating and centrifugal chillers with high seasonal efficiency;

• Variable Speed Drives for pumps and fans;

• Active Chilled Beams will be utilised in office floors;

• Heat recovery on all air handling units;

• Carbon dioxide (CO2) concentration sensors in occupied zones to optimise the ventilation rate and fresh air supply, providing energy saving as well as increased comfort;

• Segregation of high and low temperature chilled water circuits;

• Enhanced pipework and ductwork thermal insulation; and

• Water efficient fittings and recycling techniques (e.g. metering, leak detection, low water sanitary ware, rainwater harvesting and grey water recycling).

The Development will be connected to the local Citigen district heating system, which runs directly under the development site, to provide heat for space heating, domestic hot water and chilled water via new absorption chillers. Electricity will be supplied via a new EDF substation.

Furthermore, the location of approximately 300m2 of photovoltaic panels located on the building roofs will further reduce the CO2 emissions of the Development.

A target ‘Excellent’ rating under the Building Research Establishment Environmental Assessment Method (BREEAM) Offices 2008 criteria has been established for the Development with an aspiration to achieve ‘Outstanding’.

7. Demolition and Construction

All demolition and construction works are anticipated to take approximately 48 months to complete. The construction programmes of 121 London Wall and 123 London Wall will comprise the following key stages:

• Enabling and demolition works;

• 121 London Wall piling, substructure and cores;

• 121 London Wall structural steelwork;

• 121 London Wall external cladding and mechanical, electrical and public health (MEP) Installation;

• 121 London Wall internal finishes and fit-out;

• 123 London Wall piling, substructure and cores;

• 123 London Wall structural steelwork;

• 123 London Wall external cladding and MEP installation; and

• 123 London Wall internal finishes and fit-out.

The Applicant will develop, and issue to the CoL for approval, a Demolition and Construction Method Statement (DCMS) that will apply to all contractors, sub-contractors, trade and site management. The DCMS will place obligations on contractors to adopt best environmental practice, such as careful programming, resource conservation, adhering to health and safety regulations and quality procedures. The DCMS will include detailed working procedures for the control of emissions and environmental risk, and will also specify working hours.

Specifically, the DCMS will include measures for, among others:

• Neighbour and public relations, and provisions for complaints;

• Site hoarding, housekeeping and security;

• Traffic management and parking provisions;

• Road and utility diversions;

• Waste management and clean road management;

• Noise and vibration control;

• Protection of ecological, archaeological and water resources; and

• Energy and water usage.

The measures to be employed to mitigate potential construction impacts on the environment and public health and safety will be detailed within an Environmental Management Plan (EMP) and will be agreed with the CoL prior to works commencing on-site.


8

8. Waste and Recycling

The Development aims to be a sustainable building with high standards of environmental performance. As such, due consideration has and will continue to be given to the waste generated by the Development during demolition and construction, operation and eventual demolition at the end of the Development’s life.

Therefore, the waste strategy has the following aims:

• To contribute towards achieving current and long-term government, GLA and CoL targets for waste minimisation, recycling and reuse;

• To ensure that all legal requirements for the handling and management of operational waste are complied with; and

• To provide tenants with convenient, clean and efficient waste management systems that enhance the operation of the buildings and promote high levels of recycling.

A Site Waste Management Plan (SWMP) will be produced, with additional detail identifying the types and quantities of waste that will be produced during every stage of the project. The SWMP will highlight the opportunities to minimise and reduce waste generation.

9. Air Quality

The EIA has included an assessment of both demolition/construction and operational impacts to air quality. The statutory review and assessment of local air quality within the CoL resulted in the entire City being designated an Air Quality Management Area (AQMA), which includes the development site, due to exceedences of the nitrogen dioxide (NO2) and particulate matter (PM10) objectives. Consequently, Air Quality Action Plans have been prepared for the City, which have been taken into consideration in the assessment of air quality impacts.

Any impacts arising from the construction plant and associated dust generation are predicted to be of minor adverse significance at the nearest residential receptor (i.e. the Barbican Estate), lasting only for the duration of the demolition and construction phase. A number of measures will be implemented to mitigate these impacts to an acceptable level of significance. Furthermore, impacts associated with construction plant emissions and construction road traffic are predicted to be ‘imperceptible’ in magnitude and of negligible significance, following mitigation.

The potential impacts arising from road traffic associated with the completed development are anticipated to have a negligible impact, since NO2 and PM10 concentrations are

predicted to correspond to an ‘imperceptible’’ magnitude of change over the modelled baseline conditions.

The Development’s energy requirements will be supplied by the local district heating scheme (Citigen). High efficiency boilers will be included within the Development, used only for standby purposes in the event of a local district heat network failure. If required, the resultant increase due to the boilers, over background NO2 and PM10 concentrations, corresponds to a magnitude of change that is considered to be ‘imperceptible’ and of negligible significance. Nonetheless, the following industry best practice measures will be adhered to with respect to the building plant:

• Selection of suitable backup/standby combustion plant with best available technology and good thermal efficiency, where practical;

• Regular inspection of the machinery, operation to the manufacturers instructions, and ensuring that equipment is well maintained; and

• The release of backup/standby combustion emissions to atmosphere via an appropriately designed stack.

10. Archaeology and Built Heritage

An assessment of the impacts of the Development on built and buried heritage assets (i.e. above ground standing structures and subsurface archaeological remains) has been undertaken using methodologies conforming to the standards specified by the Institute of Field Archaeologists.

The site contains the remains of St Alphage Church and is adjacent to the Barbican Estate. Both are Grade II listed buildings. A Scheduled Monument (the London Wall remains) is located outside the southeastern part of the site, beyond the site boundary. Another Scheduled section of the London Wall can be found within St Alphage Gardens, partially located within the application boundary on a northwest to southeast alignment. Understanding of the preservation, nature and date of the assets on the site is high following past geotechnical investigations, two recent evaluations and a number of historic excavations around the site.

Prior to mitigation, piling works and the construction of the proposed basement would have a major adverse impact upon a truncated Roman and later medieval City ditch and later medieval burials, which are of high importance. There is a low potential for any other remains, but, if present, basement construction would have minor to major adverse impacts depending on the level of preservation.

In view of the generally low level of archaeological survival on the site and the absence of any remains of the London Wall, the impact of the Development upon archaeological remains will be mitigated by a programme of archaeological


9

investigations (preservation by record) to be agreed with the CoL and secured by a Planning Condition. In the eastern part of the site, a watching brief will be combined with archaeological excavation of a series of transects across the remains of the Roman and later medieval City ditch. The final programme of archaeological investigation will be agreed with the CoL’s archaeological advisor. Upon completion of the proposed mitigation strategies, the impact upon archaeological remains is considered to be of negligible significance.

Although the overall impact of the Development upon the St Alphage Church remains would be beneficial (in terms of its historic, communal and aesthetic values and setting) and that the impact of demolition upon the structure would be minimised, a programme of built heritage recording of the Grade II Listed St Alphage Church remains in its current setting (i.e. prior to demolition of the highwalk and podium) will be undertaken in order to mitigate the potential impact upon the fabric of the structure resulting from the demolition of the highwalk and podium. Listed Building Consent is required for the works around St Alphage Church and the demolition of the (non-listed) bridges between the highwalk and the (listed) Barbican. An application for SAM Consent will also be made in relation to the works associated with the removal of the existing stair that currently touches the top of the London Wall remains.

Upon completion of the proposed mitigation strategy, the minor adverse impacts upon the fabric of the St Alphage Church remains will have been reduced to negligible, and with the beneficial impact upon the setting of the Church, the overall impact of the Development upon the Church is considered to be of moderate beneficial significance, resulting from the enhanced historic, communal and aesthetic significance provided by the new landscaping proposals (Figure 14).

11. Daylight, Sunlight, Overshadowing, Solar Glare and Light Pollution

The Development’s potential impact upon daylight and sunlight availability to neighbouring properties, overshadowing, solar glare and light pollution has been assessed against industry standards (Building Research Establishment (BRE) Guidelines).

The presence of concrete balconies has a significant effect on suppressing the daylight and sunlight amenity to neighbouring properties. However, the retained level of daylight is in excess of the minimum standard and in most cases substantially in excess of the BRE recommended minimum standard. Daylight impacts to neighbouring properties are largely of negligible significance with some areas of the Postern experiencing impacts of minor adverse significance.

In terms of sunlight, very few of the neighbouring windows are able to comply with the BRE recommendation. For those properties which immediately neighbour the site (Andrewes House, Gilbert House, the Postern, Willoughby House and Wallside) there are 80% and 79% respectively, which are unable to satisfy guidance. This is despite the existing level of massing on the site being comparatively modest given the densely developed City Centre location and the surrounding context. This is driven to a high degree by the presence of balconies on neighbouring properties. In the event that there were no balconies, then 91% would satisfy BRE recommendations for total sunlight across the year.

Figure 14: New Open Space with St Alphage Church Remains in Foreground


10

Designing the scheme with a gap between the eastern and western elements of the proposal to enable daylight and sunlight to pass between to the south face of Willoughby, Andrewes and Gilbert Houses, has resulted in high levels of sunlight compliance. Depending upon the base level utilised, 89% and 88% of windows will either see an improvement in their sunlight, remain entirely unchanged, or experience an unnoticeable and BRE compliant alteration in sunlight.

In relation to those properties that do feature concrete balconies on their external façade, the vast majority are affected during the winter months, this being a time of year when the sun is at a sufficiently low angle of incidence for it to be able to pass beneath the concrete structure above the windows. Altering the massing on the site in the way proposed quickly interrupts this winter sunlight. However, broadly, the retained levels of winter sunlight are, generally speaking, either close to or in excess of the BRE criteria for winter months and in that way whilst there is a reduction beyond guidance, the retained values are either in line with BRE Guidance or not inconsistent for the winter months within the urban context. Sunlight impacts to neighbouring properties are of negligible to moderate adverse significance.

In shadow terms, the vast majority of amenity areas will are BRE compliant, although they will experience a small and negligible alteration in the shadow. There are 6 rooftop terraces to 6 different houses along the Postern overlooking Fore Street, which are poorly sunlit in the existing situation and do not satisfy BRE Guidance and will be worsened as a consequence of the proposal. Each of the 6 houses also have a second terrace, looking west over St Giles Courtyard and Church and away from the main street, which will be largely unaffected by the proposal. This is considered to be a moderate adverse impact and within the context of the overall high level of shadow compliance and the additional amenity space put back by the scheme, is consistent with an urban environment.

With regards to light pollution, broadly, the level of light trespass experienced by those properties immediately adjacent to the scheme and in particular the corner of Willoughby House will be less than the level of light trespass currently experienced by the existing St Alphage House tower, representing a negligible impact. This is in part due to the design of the scheme, but also due to a more considered lighting design strategy.

In terms of Solar Glare, there is the potential under certain circumstances at very particular times of the year and certain hours of the day for there to be solar glare from the building façade, dependant upon weather conditions at the time. Whilst there is the potential for solar glare impacts of moderate adverse significance, this is something which could be designed out of the scheme at detailed design stage, e.g. tilting glazing to avoid solar reflection.

12. Ecology

The existing site is situated within an area with few ecological receptors and is not subject to any statutory or non-statutory nature conservation designations. However, lying immediately adjacent to the west of the site is part of the garden complex of the Grade II Barbican and St Alphage Gardens Site of Borough Importance (SBI). The vegetation within the Barbican and St Alphage Gardens SBI includes introduced shrub, amenity grassland, and planted semi-mature trees, which all hold some potential to support breeding birds.

All on-site buildings and hardstanding have limited ecological value. There is introduced shrub planting and planted trees present on-site. Additionally, there are street trees within the pavement of London Wall. These trees are semi-mature and will provide some limited invertebrate and bird nesting habitat.

In order to identify impacts likely to have an adverse impact on the site’s ecological value and provide appropriate mitigation, the ecological impact assessment comprised the collection and compilation of existing historical ecological data; an extended Phase 1 Habitat Survey and arboricultural survey undertaken on 4 August 2010; bat surveys undertaken on 5/6 and 18/19 August 2010; and an assessment of the site’s ecological importance including an analysis of the potential of the site to support protected species, or species of conservation significance.

On-site demolition and construction activities have the potential to adversely impact the ecology of the adjacent Barbican and St Alphage Gardens SBI. Measures to prevent associated pollution risks will be fully outlined in accordance with current guidance within the DCMS and EMP. As a result, any potential ecological impacts are expected to be of negligible significance. There is introduced shrub planting and 3 planted trees present on-site, as well as 13 street trees within the pavement of London Wall to the south of the site. All of this vegetation will be lost as a result of the Development. Although not of high ecological value, they are still a foraging and nesting resource important in the context of the site. Therefore, the loss of the habitats on-site is considered to be a minor adverse impact at the site level.

No bats were recorded emerging from or returning to roost in the existing on-site buildings during the August bat surveys, therefore the demolition of these buildings is unlikely to cause any adverse impacts to bats. Furthermore, no evidence of black redstart (protected under the Wildlife and Countryside Act) or its required habitats have been identified on-site.


11

However, suitable nesting habitat may be created during the demolition and construction phase of the Development by the provision of waste ground, rubble, and tall structures with ledges and crevices, such as cranes.

If black redstarts are found on-site then appropriate mitigation measures will be implemented. Furthermore, it is recommended that site works commence outside of the black redstart breeding and dependency period, which falls between February and mid-August, in order to ensure that negligible impacts will occur. If site works are carried out between the breeding season, a series of additional black redstart surveys will be carried out.

Additionally, given the precautionary approach adopted, the potential impacts to nesting birds and mammals are also negligible. It is recommended that all clearance works commence outside of the bird-breeding season, which falls between March and August. If this is not practical, then appropriate surveys will be undertaken by an experienced ornithologist, prior to site clearance.

In the long-term, the proposed provision of new trees, landscape planting, green walls and green roofs (Figures 15 and 16), as well as additional bird nesting boxes, as described in the landscaping strategy, will ensure that any impacts to on-site vegetation are expected to be of negligible significance. Furthermore, it is considered that the landscaping strategy across the site will result in a minor beneficial impact to the local ecology.

Figure 15: Green Walls along St Alphage Garden

Figure 16: Green Roofs on 121 London Wall

13. Electronic Interference

The EIA has also included an assessment of the potential impacts to analogue, digital and satellite television (TV) reception associated with the Development. Consideration has also been given to the potential impact of the Development on radio reception and mobile telephone signals, wireless networks and emergency service communications.

In order to assess whether the Development will cause interference to broadcast reception, a combination of desk-based calculations and an on-site inspection of domestic aerial installations have been undertaken.

Prior to mitigation, it is predicted that there will be long-term minor adverse impacts to the reception of terrestrial TV services for up to 54 existing aerial installations. However, suitable mitigation measures are available in all cases, which include upgrading the existing aerials by increasing their height and/or gain or providing a non-subscription satellite service which is supplied by either the BBC and ITV (which is called ‘Freesat’) or ‘Sky’ for a one-off cost.

The Barbican Estate, located immediately north of the site, is entirely served by its own cable TV system, with the input aerial located on the roof of Cromwell Tower and as such cannot be adversely affected by the Development. Therefore, following mitigation, electronic interference is considered to be of negligible significance.


12

14. Ground Conditions

The assessment of ground conditions at the site has involved the review and collation of readily available information pertaining to the current condition of the soils and groundwater on-site. The information has been reviewed in the context of the Development to evaluate the short, medium and long-term, direct and indirect impacts.

Consideration of impacts associated with potentially contaminated soils and groundwater is made in the context of existing site conditions, construction works and site operations. The evaluation of ground conditions has also included a general geotechnical assessment of the potential for soil movement and comment on the potential for unexploded ordnance, ground gas and underground structures on-site.

Following mitigation measures, negligible impacts to the ground conditions are expected to occur throughout the demolition and construction phase of the Development. Should remediation be required during the redevelopment with respect to any identified contaminated soils associated with historical land use at the site, the remediation will result in a moderate beneficial residual impact to the local environment.

15. Noise and Vibration

An assessment was undertaken of potential noise and vibration impacts associated with the Development during the demolition and construction phase and on completion and occupation of the Development. In particular, the assessment considers potential impacts on identified receptors, in terms of:

• Predicted noise and vibration levels from demolition and construction;

• Noise and vibration from the building services plant; and

• Any increases to road traffic attributed to the Development.

The introduction of the EMP, DCMS and use of ‘Best Practicable Means’ will reduce excessive noise levels and minimise vibration impact on sensitive receptors. For the majority of demolition and construction works, noise impacts are considered to be limited to minor adverse significance. As a worst-case, demolition and construction noise is expected to have a moderate adverse impact at the nearest sensitive receptors (i.e. the Barbican Estate, Salters Hall and St Alphage Gardens) for a period of approximately 4 months.

As a worst-case, vibration will be limited to a minor adverse impact at the sections of the Barbican Estate fronting directly onto Fore Street during piling works. By

employing ‘Best Practicable Means’ to control vibration, impacts affecting both nearby residential receptors and the London Wall remains will be limited to negligible significance for the majority of works.

Increases in road traffic noise levels due to construction traffic are considered to be of negligible significance along the majority of surrounding roads.

Once the Development is completed and occupied, road traffic noise levels due to operational traffic associated with the Development are considered to be of negligible significance along the majority of surrounding roads.

Building services will be designed as to achieve the recommended operational noise limits. To control noise, plant rooms are placed to minimise noise propagating to sensitive receptors. The specification of plant machinery with low noise emission and properly attenuated supply and extract terminations will help to ensure that noise is minimised. The use of enclosures, local screening, mufflers and silencers will also be used as appropriate, and all plant will be mounted in a way as to minimise structure borne vibration. Noise and vibration impacts from the building plant are therefore considered to be of negligible significance.

Suitable façade insulation, including glazing and ventilation noise control will be provided within the Development to meet the internal noise criteria from British Standard (BS) 8233. Therefore, ambient noise inside the completed development is predicted to be of negligible significance. As there was no subjective evidence of ambient vibration during site visits, it is considered that the impact of ambient vibration affecting humans within the Development will be of negligible significance.

16. Socio-economics

The assessment of socio-economic impacts has considered the extent to which the Development conforms to relevant socio-economic planning policy at appropriate spatial levels. The key areas of potential impact that have been assessed as part of this study comprise the following:

• An economic impact assessment, including employment impact on the labour market; and

• A review of other relevant socio-economic impacts, including the demand on existing social infrastructure such as open space.

In summary, it is considered that the Development would have an overall minor beneficial socio-economic impact on the local and regional economy, through the provision of employment and through associated indirect effects during demolition and construction and once the Development is completed and occupied.


13

The Development also has a number of positive impacts on the surrounding neighbourhoods, including the provision of a safer local environment and an increase in the provision of publically accessible open space; both considered to be of minor beneficial significance.

17. Transportation and Access

In consultation with TfL and the CoL, the EIA has identified the expected number of person trips, by mode, which will be generated by the Development. In doing so, a full assessment of the impact of the Development on pedestrian movements, cycle infrastructure, public transport and the surrounding road network, has been undertaken.

In summary, the implementation of the EMP for transporting construction materials and waste to and from site would ensure that construction traffic would not cause undue disruptions to the local highway network and capacity. As such, the identified negligible impacts of the demolition and construction works will be maintained, with minor adverse impacts experienced for a short period of peak activity.

With regard to pedestrian movements during the demolition and construction phase, impacts are considered to be of negligible significance. The highwalk will be firstly diverted around the perimeter of the site during site demolition and excavation. Routes have been identified, which will enable all pedestrian trips to be made with some trip diversion whilst the highwalk network across the site is closed (Figure 17).

Figure 17: Highwalk Diversion during the Demolition Phase

Once 121 London Wall has been completed, the highwalk network will be partially reconnected with routes north-south open. Trips to the west would be diverted at ground level using the stairs proposed as part of the Development (Figure 18). Upon completion of 123 London Wall, the highwalk connection to 125 London Wall (west) will be completed.

Figure 18: Highwalk Connections following Completion of 121 London Wall

Note: Highwalk connections to City Place House (south of London Wall) will be

subject to agreement with the CoL and the building owners.

Once the Development is completed and occupied, residual impacts would range from negligible to moderate beneficial, with the Sustainable Transport Strategy ensuring that the use of non-car modes of transport is adequately encouraged. With the improvements to the London Wall footway and highwalk network, the overall impact of the Development on pedestrian journey time and delay is of moderate beneficial significance. All improvements to the pedestrian network will provide attractive and well lit spaces with high quality paving materials and legible highwalk routes. Elevators and stairways are proposed to connect the ground and highwalk levels in a central location, which will improve accessibility for all pedestrians. The Development’s impact on pedestrian amenity and accessibility is therefore considered to be of moderate beneficial significance.

18. Water Resources and Drainage

The impact of the Development on the hydrological and hydro-geological environment has been assessed through identification of the baseline environmental quality of these resources and an assessment of the potential sources, magnitudes and significance of any impacts.

The assessment has been based on professional judgement and a review of baseline data including historical site data, along with the review of relevant literature, policies and legislation.

The assessment indicates that the incorporation of mitigation measures that form part of standard practice operational guidelines, and which apply control at the source or along the pathway of the pollution, means that the overall impact on the water environment, during both the demolition and construction phase and once the Development is completed and occupied, will be of negligible significance. However, it is anticipated that during the demolition and construction phase, additional


14

water demand and wastewater generation will be of minor adverse significance, albeit of a temporary duration. Thus, the ‘worst-case’ long-term impact during the operational phase would also be minor adverse if Thames Water did not improve the local drainage network.

Without mitigation, the Development would continue to discharge surface water run-off in an uncontrolled manner to the Thames Water drainage network. In the long term, this would have a minor adverse impact. The Development will include site-specific sustainable urban drainage systems (SuDS) to attenuate surface water run-off generated by all events up to the 100-year storm plus climate change (30%) event. Surface water discharge will be restricted to Greenfield rates, which meets the requirements of Planning Policy Statement 25 (PPS25): ‘Development and Flood Risk’, the EA and the London Plan, and will result in a minor beneficial impact to the drainage network and negligible impacts to flood risk.

19. Wind Microclimate

The EIA has included an assessment of the likely impact the Development will have on the local wind microclimate, both within and around the site. Wind tunnel testing (Figure 19) has been carried out and conditions are described according to the Lawson Comfort Criteria. The Criteria describe wind conditions according to the pedestrian activities that each of the various conditions are suitable for (e.g. sitting, standing/entrance, leisure walking, business walking and car park/roadway use).

Figure 19: Model in the Wind Tunnel

The baseline conditions show that presently the site has a relatively calm microclimate, suitable for a range of conditions from sitting to leisure walking. The windiest conditions at the existing site are experienced by locations in the northeast area of the site (suitable for leisure walking), and are caused by southerly and northwesterly winds accelerating around the corner of Moor House. During the summer season, the wind microclimate is generally one category calmer, and conditions at all ground

level locations are suitable for a range of conditions from sitting to standing/entrance. The existing wind conditions along the Barbican Estate (located immediately to the north of the development site) are suitable for sitting or standing/entrance use throughout the year.

In the presence of the Development, the wind microclimate at ground level is generally suitable for sitting and standing/entrance use, representing negligible to moderate beneficial impacts throughout the year. The Development will also provide some shelter from the prevailing winds to the Barbican Estate, where measured conditions are slightly calmer than those measured for the existing site and suitable for sitting or standing/entrance use. The impact at these locations is considered negligible (e.g. at gardens/amenity areas) to minor beneficial (e.g. at thoroughfares).

The proposed highwalks experience wind conditions suitable for sitting and pedestrian standing/entrance use. The impact at these locations, which are thoroughfares, is minor to moderate beneficial all year round.

The proposed open terraces at roof level on 121 London Wall are relatively exposed to winds blowing from a wide range of directions. However, the “stepped” profile of the roof and the balustrades around the terraces provide some degree of shelter to these areas. The wind microclimate at roof level is generally suitable for sitting or standing/entrance throughout the year, representing negligible to minor beneficial impacts. However, the southern open terrace is suitable for leisure walking, which represents a minor adverse impact.

As these areas are intended as outdoor amenity space, sitting conditions should ideally be the target during the summer season, with standing/entrance conditions acceptable during the winter. For this reason, the following mitigation is provided on the southern open terrace in order to locally enhance the wind microclimate by one category throughout the year:

• Suitable landscape planting (e.g. hedges/bushes), particularly located along the south and west perimeter and in the central areas of the terrace and recessed from the terrace perimeter, extending to a height of 2m, would generally enhance the wind microclimate in the roof terrace, especially during the summer months, when the trees are in leaf and the open area is more likely to be extensively used.

With the above mitigation in place, the wind conditions on the southern open terrace are expected to be suitable for their intended use, representing a negligible impact throughout the year.


15

20. Townscape, Conservation and Visual Impact Assessment

Volume II of the ES, prepared by Professor Robert Tavernor Consultancy, provides the Townscape, Conservation and Visual Impact Assessment of the Development. A total of 32 views were selected in consultation with the CoL to enable the Development to be assessed from within the surrounding locality. The views illustrate the potential impact of the Development on existing views, and its relation to its urban context.

In conclusion, the design of the Development will provide this specific part of London with a positive local architectural and urban statement, both when seen in isolation and in relation to other tall buildings locally, existing and consented. It will enhance not harm the settings of nearby Conservation Areas and listed buildings within which it is situated. The proposed buildings and public realm and urban landscape into which they will be set will be of the highest architectural and urban design quality, and will integrate successfully with the existing organisation and character of buildings and spaces on the site and in the surrounding area.

Overall, the Development will relate well to existing and consented buildings, and due to the high design quality of the Development and by recognition that modern buildings of high design quality do not harm the settings of historic buildings; associated impacts will be of minor to major beneficial significance throughout.

21. Cumulative Impact Assessment

The assessment of cumulative impacts has been based upon the information available at the time of writing and currently available assessment techniques. For the cumulative assessment, two types of impact have been considered:

• The combined effect of individual impacts; for example noise, airborne dust or traffic on a single receptor; and

• The combined impacts of several development schemes which may, on an individual basis be insignificant but, cumulatively, have a significant impact.

A list of development schemes proposed by way of the submission of a planning application, consented/with a resolution to grant consent, or currently under construction, that have been included within the cumulative impact assessment is provided below:

1. Telephone Exchange, Moor Lane and Retail Unit at 72 Fore Street;

2. Roman House;

3. 21 Moorfields;

4. Milton Court;

5. One New Change;

6. Walbrook Square;

7. New Court;

8. The Walbrook (St Swithin’s Walbrook and Granite House);

9. Bishopsgate Tower (The Pinnacle) 22-24 Bishopsgate;

10. 110 Bishopsgate, Heron Tower;

11. Stone House and Staple Hall, Bishopsgate;

12. 100 Bishopsgate;

13. 122 Leadenhall Street;

14. Cannon Street Station;

15. 20 Fenchurch Street;

16. 6 Bevis Marks; and

17. 78-86 Fenchurch Street.

The locations of these schemes are illustrated in Figure 20.

Figure 20: Location of the Cumulative Schemes


16

In addition to the developments listed above, impacts associated with both the construction and operation of a new Crossrail Station at Liverpool Street have also been considered within the cumulative impact assessment. Construction is scheduled to begin in late 2011 and be completed in 2016, and the station will feature four main worksites located at Moorgate Underground Station; Liverpool Street Station; Finsbury Circus; and Blomfield Street.

Demolition and construction activities are predicted to result in impacts ranging from negligible to moderate adverse for noise, vibration, air quality and dust emissions. It is therefore reasonable to predict that there will be a minor to moderate adverse impact on nearby sensitive receptors from the combined effect of individual impacts (mainly relating to temporary plant noise, vibration and dust). This impact will be temporary in nature (i.e. reversible), lasting for the duration of the demolition and construction programme and is considered to be normal for such a large-scale development. It is considered that the benefits to the local community once the development is complete will outweigh the temporary nuisance impacts experienced throughout the demolition and construction programme.

When considering the combined effects of the Development with the schemes detailed above, whilst it is acknowledged that some adverse impacts will be experienced should construction activities overlap (i.e. minor to moderate adverse impacts in relation to dust, noise and vibration), overall, however, it is considered that on completion of the development, cumulative impacts will be beneficial in nature. Such impacts will largely relate to improvements to the public realm and local ecology; improvements to the local wind microclimate; a reduction in the stock of contaminated land in the City; improved surface run-off management; the provision of additional commercial, retail, and leisure space; and the provision of additional employment opportunities.

With regards to the townscape, conservation and visual cumulative impacts, the Development has been designed so as to relate successfully to both the existing schemes and consented schemes in the local area and on the skyline.

The Development will be read in relation to a lower tier of existing, new and consented tall buildings at the western edge of the City, which will be distinct from the clusters of towers emerging at the northern gateway to the City and, taller still, at the City’s core, which will be set further east and to the far (right) of the development site and of St Paul’s Cathedral in views from the River. Cumulative impacts will be of minor to major beneficial significance.

22. Residual Impacts and Conclusions

Residual impacts are defined as those impacts that remain following the implementation of mitigation measures. Mitigation measures relate to any of the three key phases of the Development (i.e. design, construction and operation) and are discussed in full within the relevant technical chapter of ES Volume I. In addition, each technical chapter also contains detailed consideration of both positive and negative residual impacts arising.

Throughout the demolition and construction programme, short-term (temporary) minor to moderate adverse impacts are anticipated, especially in relation to noise, vibration and air quality (dust). However, the overall conclusion of the EIA is that the Development will have an overriding beneficial impact on the City and Greater London and will, in many ways, regenerate and enhance the site and contribute the setting of the wider area. Whilst it is acknowledged that some adverse impacts will be experienced during the site preparation and construction phase of the development, the benefits of bringing the Development forward are considered to far outweigh any temporary construction impacts.

In particular, the presently underused site will be redeveloped with high quality commercial accommodation, providing economic benefit through job creation during the construction and operational phases. The Development will significantly enhance the setting of the Grade II Listed St Alphage Church and London Wall remains, and lead to an improved public realm, through enhancements to the site’s biodiversity, the incorporation of safety and security measures to offer a safer local environment, and significant improvements to pedestrian accessibility and amenity. Furthermore, the Applicant is committed to achieving a Building Research Establishment Environmental Assessment Method (BREEAM) rating of ‘Excellent’ with aspiration towards ‘Outstanding’.

The Development accords with the Development Plan and other material considerations and, through the provision of high quality flexible office accommodation, will enhance the CoL as a globally attractive finance and business location and generate capacity to meet current and future office demand.


17

Contacts and Availability of the ES

The ES is available for viewing by the public during normal office hours at the Planning Department of CoL. Comments on the planning application should be forwarded to CoL at the following address:

Planning Department City of London PO Box 270 Guildhall London, EC2P 2EJ

Additional copies of the Non-Technical Summary are available free of charge in electronic form, while copies of the full ES are available for purchase from:

Hammerson (Centurion) Limited 10 Grosvenor Street London W1K 4BJ

london wall place 121-123 london wall, ec2 - iema · as london wall place, 121-123 london wall ec2...

Documents