Westminster City Council King Street Low Carbon Trial

Author: Ivan Farrell Reviewed by: Vanessa Hilton & Phil Clark Draft: 01/06/2021

WESTMINSTER CITY COUNCIL KING STREET LOW CARBON TRIAL

© FM Conway This document is the copyright of FM Conway and the information therein may be the subject of a pending or granted patent. It may not be reproduced or used for any other purpose than for which it is supplied without the written permission FM Conway.

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TABLE OF CONTENTS

3 5 6 7 7 7 8 11 11

Executive Summary

33 35 36 37 38 40 47 50 52 53 54 55 56

Embodied Carbon Overall Carbon Usage

Introduction Background

Other Environmental Benefits

Scope

Site Feedback Testimonials Financial Impact

Limitations

Aims & Objectives Scheme Details

Conclusion

Baseline

Recommendations

Comparison between King Street & Marlborough Hill

Article – Highways Magazine

14 14

Methodology

Article – Asphalt Now

PPM Standard Works Method – Marlborough Hill

Article – Asphalt Industry Alliance

Article – NLA. London

15

King Street Deviations from Method - Operations King Street Deviations from Method - Specification PPM King Street Works Method

Article – UK.100

15

60

Appendix 1 – King Street Operations Carbon Footprint Appendix 2 – Marlborough Hill Carbon Footprint Appendix 3– Supervisor Check Sheet – Site Set Up Appendix 4 – Supervisor Check Sheet – Daily Record Appendix 5 – Lessons Learnt Feedback from Site Staff

17 17 18

61

Power Supply Specification

62

20

Plant

21

Materials

64

23 25 26 29

Transportation

Suppliers

66

Marketing Campaign

Results

TABLES & GRAPHS

9 11

Figure 1 - General Arrangement Drawing for King Street Figure 2 - Shows the differences between the two schemes. Figure 3 - General Arrangement Drawing for Marlborough Hill Figure 4 - Westminster Footway Reconstruction Comparison Table

12 16 16

Figure 5 - Drawing of Current Specification – Footway Reconstruction (Scale 1:10)

16 Figure 6 - Drawing of Marshalls’ Specification (50mm slab Thickness) – Footway Reconstruction (Scale 1:10) 18 Figure 7 - Charging Point installation to power supply 19 Figure 8 - Charging Point installation to power supply 20 Figure 9 - The JCB excavator in action on King Street 23 Figure 10 - Demonstrates the sustainable products and plant used 25 Figure 11 - Speedy Hire Electric Taxi Delivery Vehicle 30 Figure 12 - Graph Showing the Comparison of Operational Carbon Produced on King Street & Marlborough Hill 31 Figure 13 - Pie Charts Showing the Carbon Produced by Type Across Both Schemes 32 Figure 14 - Graph Showing the Carbon Breakdown Across All Operations 33 Figure 15 - Bar Chart Showing the Total Carbon Footprint at both sites 34 Figure 16 - Graph showing how the embodied carbon is broken down 35 Figure 17 - Table showing the whole tCO2e carbon footprint for both schemes: 35 Figure 18 - Table showing the King Street carbon savings 42 Figure 19 - The table below shows the approximate costs of the extraordinary items 43 Figure 20 - Stacked Graph showing the additional costs against the scheme estimate

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EXECUTIVE SUMMARY

This report provides an analysis into the King Street Low Carbon Trial by evaluating the carbon reduction measures introduced on the scheme. This was the first time that carbon was measured for a scheme in Westminster and now sets the baseline for monitoring carbon usage and measuring the savings that can be made by changing methods and/or materials. The report has split the carbon savings into:

• Operational Carbon – based on FM Conway’s carbon outputs for installing the scheme

• Embodied Carbon – which considers the greenhouse gases emitted throughout the production of the materials, from extraction of raw material, through manufacturing process and transportation to site. It also takes into account the expected lifecycle of the product The report primarily concentrates on the elements of work within FM Conway control, such as travel, deliveries, and operations, but also reviews the embodied carbon within materials. The working operations, including travel and deliveries were recorded daily with the carbon then calculated using the UK Government Conversion Factors for Greenhouse Gas (GHG) Reporting 2020, published by the Department for Business, Energy and Industrial Strategy and the Department for the Environment, Food and Rural Affairs. The full workings are contained in the appendices. The results of the trial have been compared to a standard Planned Preventative Maintenance (PPM) scheme of a similar size and scope, Marlborough Hill, running during the same timeframe to establish the carbon savings made against traditional construction techniques. The embodied carbon contained within the site materials was measured by a tool designed by Metis Consultants Limited on behalf of Westminster City Council. For the trial only, a minor change to the specification was installed to maintain the same look and feel to the street, meaning that there was a limit to the carbon that could be saved. • 79% carbon saving in operational delivery against a standard scheme - 1.74t of carbon was emitted during the operational phase of the scheme, saving over 4t when compared to the comparison site at Marlborough Hill, which equates to just 0.04t per day • 46% carbon saving per m2 in the materials used. The paving slabs were reduced to 50mm from 63mm, with the foundation 58mm shallower and using concrete sub-base grade C10 instead of C20, which reduced the embodied carbon to 17.93t, making a saving of nearly 23t against Marlborough Hill and 53% more carbon efficient overall with a total carbon saving of 27t It was accepted at the outset that there would likely be a trade-off between cost and carbon to make significant carbon savings. The final cost of £94,000 was £53,000 higher than the estimate to carry out the works with traditional techniques. However, it is noted that there were several extraordinary costs against the scheme that would not normally be incurred. The key results of the trial are:

In addition, it is expected that these costs would reduce as electric plant becomes more readily available and is able to service several concurrent schemes on the programme.

It has been calculated that £45,000 of these costs were classed as extraordinary costs, thereby making the like for like comparison £49,000 for a carbon efficient scheme, against £41,000 for a diesel-powered scheme. Therefore, a cost uplift of 20% has saved over 50% of carbon on this scheme. This was the first trial of its kind in the UK and there are challenges for a wider rollout, including the lack of electric charging points for vehicles and plant, limited plant options available from suppliers and the cost of making the change.

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In completing the trial, it has identified several recommendations to further reduce carbon across the Westminster network including:

• Prohibiting diesel from work sites

• Increasing the electrical power points available across the City

• Seeking alternative power sources for equipment

• Investigating the use of central compounds to reduce travel

• Running concurrent sites using electric powered operations to increase efficiency

• Working closely with suppliers to increase the availability of plant

• Increasing the ability to monitor energy usage and diesel usage across projects

• Reviewing current specifications to identify carbon savings in embodied carbon

• Trialling of lower carbon materials on the network

• Designing a scheme from early stages to investigate more specification carbon savings

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INTRODUCTION

In response to the climate emergency, FM Conway has undertaken a low carbon trial in King St, SW1 on behalf of the City of Westminster. The works involved relaying a footway on the PPM programme using more carbon efficient methods than the standard practice. The aim of the trial was to take a standard PPM scheme, and identify areas of change that would reduce the carbon output of the scheme. It concentrated on electrifying the working operations and removing some of the cementitious materials in the build-up of the paving. It is the first scheme of its kind in the UK, providing both a blueprint for Westminster and FM Conway for future PPM schemes, as well as a challenge to the industry in tackling carbon reduction over the next decade. A target of 75% carbon saving for operations on the scheme was set. It was hoped that by reducing the thickness of the slab that 25% savings could be made on the embodied carbon within the materials.

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BACKGROUND

Westminster City Council has one of the worst air pollution problems in the country and in September 2019 declared a climate emergency. A target was set to make council activities carbon neutral by 2030 and the Leader of Westminster Council has set this as the top priority. This is an overall council initiative and is being led by the Westminster City Council Corporate Team. To support the corporate goals, the City Highways Team asked the Asset Board, led by Andy Foster, to look at how works on the public highway could be carried out in a more carbon efficient manner. The Asset Board is comprised of members of Westminster City Council and key members of the FM Conway delivery team across all the Highways contracts. A Carbon Working Group was set up to focus solely on carbon reduction, which consisted of Andy Foster, Dan Perks, Westminster Operations Manager and Ivan Farrell, FM Conway Performance Manager. The group was tasked with understanding the existing carbon footprint, determining the requirements to lower it, and finding a way to introduce new measures and innovations. Andrew Cox, FM Conway SHEQ Director was invited into the group to bring industry expertise and advise on other FM Conway initiatives across London and the South East. A workshop was organised with all the Westminster contract leads to look at some of the key areas of improvement across:

• Materials

• Waste

• Design

• Work Methodology & Operations

• Plant & Tools

• Deliveries

• Travel

Several good ideas were raised, particularly around specification, electric vehicles and plant. The group determined that good planning and input around the design stage, looking at the reuse of materials and less reliance on granite from China, were key areas of focus. The next step was to implement these ideas into schemes on the programme and so the PPM programme was chosen where it is normally a ‘like for like’ replacement, so only minor amendments would be needed to the design.

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SCOPE

The scope of the report is limited to the installation of the King Street Low Carbon Trial and the Marlborough Hill PPM Footway Replacement Scheme. The primary focus is the effect of changes to operational methodology to reduce carbon. The report has not looked at any other schemes or initiatives in the public realm, or across the other contracts.

LIMITATIONS

The report is limited by the data produced at the two schemes. They are two typical PPM footway schemes, but they do not reflect works on larger public realm schemes, PPM carriageway schemes or other parts of the contract such as Lighting, Water & Drainage or Structures. Therefore, whilst the recommendations may be viable for PPM, they may be less suitable for other types of works. Note that the jobs were already designed which meant that only minor amendments could be made to the specification. A newly designed scheme would allow for more carbon-friendly measures to be considered. A further limitation is the current availability of electric plant, lack of low carbon paving materials, and scarcity of power points for charging electric equipment.

AIMS & OBJECTIVES

It was agreed that the trial would remain close to the ‘Westminster Way’ and ensure that the finished look of the street was in keeping with the rest of the area. The specification was adjusted to incorporate a thinner slab and a low carbon concrete alternative. The aim and objective was to test what carbon efficient plant is available for live sites now, with the scheme being assessed against a comparison site at Marlborough Hill. The outcomes were to establish:

• Carbon savings that can be made

• Cost of a shift to non-diesel plant

• Operational issues of change

• Barriers to achieving success

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SCHEME DETAILS

King Street is a one-way street from St James’s Square to its junction with St James’s Street and features an existing footway constructed of Artificial sone paving (ASP) with areas of granite setts and block paving. It was selected for the maintenance programme due to its high score on the Annual Condition Survey (ACS). The street featured a life-expired footway with instances of cracked slabs, uneven surfaces and poor utility reinstatements which were too large an area to be treated under reactive maintenance. The works design was to raise the kerb line to deter vehicle overrun and replace the existing paving with new ASP slabs.

It was considered a good location for the trial because:

• At 268m² it was not too big to trial new equipment whilst being large enough to test results

• It was a slab replacement scheme meaning deep excavation was not required

• Existing electric excavators were considered adequate for the work involved

• The footway was wide enough to install a feeder pillar for power

• There was enough space on the carriageway to house the welfare unit and plant within one compound • The street usage was mainly business use, many of which were closed for lockdown, meaning minimum disruption

• There was easy access to several tube stations for travel to site

• The site was close to City Hall for client visits

• There was a suitable compound at Carlton House Terrace, less than five minutes away for storage of paving materials

• It was not a heavily trafficked road, making access easy for the excavator

As Figure 1 demonstrates, the only amendment to the specification was to reduce the slab depth, meaning there were no significant changes to the design and the use of electric tools and plant were direct replacements for the usual diesel and petrol tools.

The estimated cost for the scheme was £41,000 based upon the traditional methods of installation.

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Figure 1 - General Arrangement Drawing for King Street

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BASELINE

There are no existing facts on carbon usage for highways within Westminster and there is scarce data across the industry to enable us to understand how much carbon is created on a standard footway scheme. To create a baseline carbon footprint of a standard scheme we identified a comparison site of a similar size and value. A PPM footway scheme on Marlborough Hill was selected as it had a value of £35,500 with the works predominantly ASP replacement (Figure 2 and 3). The results were evaluated and transferred to individual spreadsheets (Appendices 1 & 2) per scheme to calculate the carbon scores. A Supervisor Check Sheet (Appendix 3) was created to record all vehicle movements, deliveries, plant operations and welfare usage. The same site supervisor looked after both schemes and completed the sheets daily whilst each job was on site to ensure consistency To understand the difference in cost we compared the design estimate against the final turnout cost. However, a ‘like for like’ comparison was difficult because the current schedule of rates was built from plant, labour and material costs. As such, the costs were compared to the existing cost estimate for standard delivery.

COMPARISON BETWEEN KING STREET & MARLBOROUGH HILL

Figure 2 - Shows the differences between the two schemes.

Marlborough Hill

King St

Estimated Value

£35,500 306m2

£41,000 268m2

Paving (m2)

Kerb (m)

108m 32m2 61m3

124m 37m2 29m3

Kerb line Asphalt (m2) Excavation (m3) Excavator Model EV Charging Points

KUBOTA KX015-4

JCB 19C-1 Etec Excavator

N/A

2 x 22kv CityEV Chargers & FP Relocate 8no & reused 8 from other scheme WackerNeuson AP1850WE

Cycle Stands

N/A

Wacker Model

Belle PCLX320 STIHL TS410

Saw Model

Hasqvarna K535i

Welfare Unit Type Grab Lorry Fuel Type

Eco – With Diesel Generator

Eco – With Electric Connection

Diesel Diesel

HVO HVO

Delivery Vehicle Fuel Type No of Operatives on Site Operative Travel Type Supervisor Travel Type

3

3

Diesel Van, Public Transport

Electric Van, Public Transport

Diesel van

Electric van

11

12

Figure 3 - General Arrangement Drawing for Marlborough Hill

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METHODOLOGY

PPM works are designed to improve the condition of the council’s asset and prolong its lifespan. In general, the footway works will involve the replacement of the paving with the same type of material, for example ASP. The condition of the whole network is assessed annually, with the worst performing streets identified. An agreed programme is then produced according to the budget, with the schemes designed showing the extents of the footway to be replaced and any other associated works. The site team then take possession of the site, fence off the area and sign the site to Chapter 8 of the Safety at Street Works and Road Works Code of Practice. The Welfare Unit for the operatives is located near to the works area and is powered by a diesel generator. Materials are usually delivered to site by a diesel grab lorry if it is an FM Conway product such as concrete. Items such as paving slabs are usually delivered from Marshalls’ depot in Sittingbourne, Kent on a diesel low loader with a mechanical offload and there may be several deliveries within the duration of a scheme. Travel to site can vary depending upon location and activities undertaken. The supervisor will travel to numerous sites during the day in a diesel panel van and usually at least one member of the team will drive to site in a 3.5t diesel lorry. The excavator driver will normally travel to site on a 3.5t diesel lorry with a trailer for the excavator.

When not in use on the site the excavator will be re-mobilised on other sites until required again.

PPM STANDARD WORKS METHOD – MARLBOROUGH HILL

The standard method for relaying the footway is to:

1. Take up and relay the kerb line, replacing defective kerbs where necessary using a 1.5t diesel excavator

2. Take up the existing paving materials with the excavator

3. Excavate the sub-base to the required level using the excavator

4. Level the sub-base by hand

5. Install the sub-base concrete, use a diesel wacker plate to level

6. Prepare the paving area by hand

7. Lay the sand and cement paving bed (masonry work)

8. Lay the paving slabs, with any cuts carried out with a petrol disc cutting saw (masonry work)

9. Hand point joints with a sand and cement mix

10. Reinstate the kerb line to match the existing asphalt

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KING STREET DEVIATIONS FROM METHOD - OPERATIONS

For the King Street trial most of the operations took place as per the standard methodology. However, no diesel vehicles or plant were permitted on site.

Staff, operatives and visitors were required to attend site by a sustainable mode of transport and materials were delivered to site by an electric vehicle or cargo bike where possible.

At present there are very little or no options for sustainable larger vehicles such as grab lorries. For internal deliveries where these vehicles were used, diesel fuel was replaced by Hydrotreated Vegetable Oils (HVO). HVO is a renewable diesel alternative and is one of the world’s cleanest fuels on the market. It eliminates up to 90% of net greenhouse gas emissions such as CO2 and hugely reduces nitrogen oxide (NOx), particulate matter (PM) and carbon monoxide (CO) emissions. For the paving and grouting delivery from Marshalls, a single delivery was made to a central hub as the supplier could not commit to converting to HVO for a single journey. The final mile delivery to site came via a grab lorry on a ‘just-in-time’ basis.

The following plant was used instead of the usual specification:

• Electric Welfare Unit

• Electric 1.5t Excavator

• Electric Wacker Plate

• Electric Disc Cutting Saw

KING STREET DEVIATIONS FROM METHOD - SPECIFICATION

The scheme had already been designed using ASP as standard paving, therefore, to avoid a complete redesign and maintain the look and feel of the street, it was decided to keep the material the same. The team had a discussion with the paving supplier Marshalls to understand if there were any alternative low carbon slabs on the market. Due to the highly cementitious content within the slabs and the method of production at present there is very limited choice available, and to maintain the current aesthetics there are none. However, the option of reducing the thickness of the paving slab allowed for some carbon reduction as standard ASP slabs used in Westminster are 63mm thick, whereas Marshalls have a standard 50mm paving slab. They estimated that by making this change, 4kg/m2 of carbon could be saved. Further work on the specification by Marshalls showed that the slabs could even have a shallower foundation if the correct grout and pave bed were to be used.

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See Figure 4 for the comparison between the two specifications:

Current Spec - 750x600mm ASP

Marshalls CAT 2: GVW 3,500kg - 750x600mm ASP

Surface Course: 750x600

Surface Course: 750x600 Joints: Marshalls Pavepoint

63mm

50mm

Joints: Mortar

10mm

6-10mm

Laying Course: Marshalls Pavebed + Primer (Pavebond) Road-base: C8/10

Laying Course: Sand Cement Road-base: C16/20 Sub-base: Existing

50mm

30mm

100mm

75mm

N/A

Sub-base: Type 1

100mm*

Depth

213mm

Depth

155-255mm

Figure 4 - Westminster Footway Reconstruction Comparison Table

*100mm sub-base is optional based on the existing conditions, if the reconstruction of the footway is already on well compacted ground with CBRs greater than 30% this can be omitted. For King Street this was not required. Therefore, the construction depth was 155mm and a reduced depth of 58mm. The only other potential change was to explore if low carbon concrete could be used within the road base.

The drawings below illustrate the difference in specification for the footway construction.

Figure 5 - Drawing of Current Specification – Footway Reconstruction (Scale 1:10)

Figure 6 - Drawing of Marshalls’ Specification (50mm slab Thickness) – Footway Reconstruction (Scale 1:10)

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PPM KING STREET WORKS METHOD

The low carbon method for relaying the footway is to:

1. Take up and relay the kerb line, using a 1.5t electric excavator

2. Take up the existing paving materials with the excavator

3. Excavate the sub-base to the required level using the excavator

4. Level the sub-base by hand

5. Install the sub-base concrete, use electric wacker plate to level

6. Prepare paving area by hand

7. Lay grout paving bed by mason

8. Prime and then lay the paving slabs, with any cuts carried out with an electric disc cutting saw (masonry work)

9. Fill the joints using Marshalls’ Pavepoint

10. Reinstate the kerb line with Greenpatch, a hand-laid asphalt

POWER SUPPLY

Power supply was one of the greatest challenges to the trial as it was impractical to take the electric excavator and electric plant off-site to be charged, so a solution to charging on site had to be found. A 32 amp supply from existing street furniture such as lighting columns is currently not available and the power pack required a 63 amp three-phase supply, so a feeder pillar with a three-phase 100 amp metered supply was installed. Our ambition was to utilise a JCB power cube, which could have delivered 15kVA of power output through lithium-ion batteries. This could have been charged by an on-site feeder pillar or taken away to a depot to charge, which would have made charging of all site equipment very easy. However, JCB are still waiting for full approval to supply them. The lead time to obtain the feeder pillars was quite substantial (partly due to COVID-19) and the installation was required at least one week prior to the commencement of construction to allow for any installation delays or COVID-19 related issues. As the job could not commence without the feeder pillars and power supply, it was crucial that this phase was complete in time to plan the logistical set up. The power was required to charge the power pack and the welfare unit, and as a legacy to the project it needed to convert into two EV charging points to be used when the works were complete. Unfortunately, when we were informed that the power pack was not available, the feeder pillar needed to be adapted to allow direct power charging of the electrical equipment. In addition, we learnt that the plant had different connections that needed to be accommodated, which would have worked better if the power pack had been available for use. This was installed the week preceding the scheme going to site and connected to the power with a primary UK Power Network (UKPN) connection. The full specification is shown in Figure 7 and Figure 8.

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SPECIFICATION

MBA DD3/1500 Double Door EV Charging Pillar

Figure 7 - Charging Point installation to power supply

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Figure 8 - Charging Point installation to power supply

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PLANT

It was understood at the outset that the removal of diesel from the site would provide the biggest operational savings. However, due to the reliance on diesel vehicles and machinery within the industry and the limited choice and availability of electric plant, it meant that this saving would be limited. Both JCB and Speedy hire were engaged prior to the trial in order to secure the best equipment available. JCB offered a free trial of a JCB 19C-1 Etec Excavator (Figure 9), which was the perfect size for the shallow excavation required on this scheme. It was understood that as the excavator does not match the power of its diesel alternative that it would take longer, but would still be able to meet the programme demands.

Figure 9 - The JCB excavator in action on King Street

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The excavator would also have been easily charged with their own power pack, but they needed to provide a separate adapter to connect to the feeder pillar. As the excavator was offered as a free trial, no other options were considered, however other suppliers such as Kubota and Caterpillar are developing their own electric mini excavators.

Speedy Hire supplied the following equipment:

• WackerNeuson AP1850WE wacker plate

• Hasqvarna K535i disc cutter

To retain the look and feel of the St James’s area it was decided not to deviate too far from the existing artificial stone paving. This meant there was limited scope for reducing the carbon through a specification change. Across other parts of the City, it may be possible to explore other materials, such as recycled slabs or asphalt, which would require a larger input from the design team and a longer lead time. MATERIALS The Welfare Unit was adapted to run off electricity and solar rather than a diesel generator. This worked well as it was silent when switched on and the benefits were that the site team could use the Unit earlier without being a nuisance to the residents. The one drawback was that the hut could not be relocated as it was connected to the feeder pillar. Under normal circumstances they seldom need to be moved, however, due to an unexpected incident outside of our control involving loose masonry on an adjacent building, a scaffold needed to be erected overhead. This meant that the Welfare Unit and compound could not be used until it was safe to do so which resulted in a time delay. These items were used when required and worked almost as well as their fossil fuel powered counterparts. The wacker plate was quite heavy and difficult to manoeuvre but there was not any significant difference in terms of performance or time taken to carry out the activity. The disc cutter worked quite well cutting through the slab, assisted by the fact they were only 50mm thick. However, the battery needed to be changed after every eight cuts, meaning that a fully charged spare battery needs to be ready each time the saw is used. Another concern was its ability to cut through granite kerb if required, as this would take longer, and the battery may not be powerful enough to cope. SPECIFICATION Following discussions with the paving supplier Marshalls it was decided that the slab could be reduced to 50mm thick instead of the usual 63mm. To ensure that there was no reduction in strength Marshalls also designed the foundation. Mortar bedding with primer was specified to provide extra cohesion than sand and cement, which also enables the slab to take the impact of vehicle overrun in the same manner. The deviation from the standard also allowed the team to use a less carbon intensive C10 concrete instead of C20 without any reduction in performance. It was hoped that a low carbon concrete could also be trialled, however, it is not yet readily available as a dry, lean mix used for this type of works. Usually, the kerb line is then reinstated to match the existing carriageway. On King Street this was replaced with GreenPatch, a product manufactured with recycled asphalt and no petroleum-based ‘cut back’ solvents and hand-laid cold. STORAGE To reduce the size of the storage area on site and to replicate the workings of a centralised depot, a separate compound area was set up on Carlton House Terrace. This was less than a mile from site and allowed ‘just-in-time’ deliveries and reduced vehicle movements to King Street.

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TRANSPORTATION

DELIVERIES The largest items were the paving slabs which came from the Marshalls’ depot in Sittingbourne. These were delivered on a low loader to the compound on Carlton House Terrace. The slabs were delivered to site by an FM Conway grab lorry, powered by HVO on a ‘just-in-time’ basis. This meant that the compound on site was kept to a minimum and there was more room to store the excavator securely. Speedy Hire have an electric delivery vehicle which was not available at the time of the trial, but they delivered their equipment in a HVO transit van. All FM Conway delivery vehicles were fuelled with HVO and these made the bulk of visits to site. For smaller items like PPE, we trialled the use of a cargo bike, which is completely sustainable and can carry up to 250kg. During peak hours, deliveries via cargo bike from the Mandela Way depot in Southwark were actually faster than by lorry. To keep the carbon footprint low, no diesel was allowed on site. All deliveries and visitors to site had to use the most sustainable method available to them. Suppliers were asked to deliver either with electric vehicles, or where this was not possible, replace diesel with HVO fuel.

Figure 10 - Demonstrates the sustainable products and plant used

Product/Plant

Supplier

Delivery Method

Excavator

JCB

HVO 7.5t Lorry

Wacker

Speedy Hire Speedy Hire FM Conway FM Conway FM Conway FM Conway Marshalls

HVO Transit Vehicle HVO Transit Vehicle

Disc Cutter Welfare Unit

HVO 7.5t Lorry

Paving Materials

HVO Articulated Lorry

Aggregates

HVO Grab Lorry HVO Grab Lorry HVO Grab Lorry

Concrete

GreenPatch Asphalt

Consumables

FM Conway Stores

Cargo Bike

Waste

FM Conway

HVO Grab Lorry

HVO FUEL Hydrotreated Vegetable Oil (HVO) is a synthetic paraffin fuel that is a direct replacement for diesel as there is no need to modify the existing engines or infrastructure. It is claimed that it reduces greenhouse gases by up to 90% compared to diesel, but for this exercise we have used a more conservative estimate of 50% carbon savings. For now, there are no electric or hydrogen alternatives for larger vehicles, so this is the most carbon efficient way to fuel deliveries. However, this is only an interim solution, as it is hoped that vehicle manufacturers will have electric vehicle options in place well before Westminster’s 2030 deadline for carbon neutrality.

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TRAVEL TO SITE Electric panel vans were provided to the site supervisor and the mason (see Figure 2.5), whilst other operatives used public transport to get to and from work.

Figure 2.5

SITE VISITORS Visitors to site were requested to either travel to site on public transport or via electric vehicles if they had access to one. Some initial site meetings took place via Microsoft Teams to avoid too many people on site during the pandemic. A VIP day was arranged to allow The Westminster Cabinet member for Highways and the Environment, Andrew Smith to see the works in action. He was joined by Westminster Highways Head of Operations Phil Robson, FM Conway CEO Adam Green, and FM Conway Managing Director Andrew Hansen.

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Early engagement with key suppliers was key to the success of the trial as it allowed them to demonstrate their own sustainability credentials and express their excitement at being linked with the project. SUPPLIERS

KEY SUPPLIERS The key suppliers for this project were:

• JCB – Excavator

• Speedy Hire – Electric tools and plant

• Marshalls – Paving slabs

JCB were keen to get their product trialled on a high-profile scheme and provided their excavator free of charge, which showed a commitment to carbon reduction and the willingness to forge a partnership going forward. Speedy Hire also stock a number of different electric items and provided the HVO fuel for the trial. They provided disc cutters from Stihl, Milwaukee and Hasqvarna to try out prior to the job before the team decided that the Hasqvarna model was most suitable. They have also pledged to reduce carbon and have an electric taxicab for deliveries (see Figure 11), which unfortunately was not available at the time of the trial. Likewise, Marshalls have been doing a lot of work in the background to reduce their carbon footprint by looking at their processes and have developed their own carbon calculating tool. The team assisted FM Conway in making the biggest single carbon saving by providing the thinner slab and advising on the shallower foundation for it. We hope to continue working with Marshalls to trial further paving options for carbon reduction in the future.

Figure 11 - Speedy Hire Electric Taxi Delivery Vehicle

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To support the works on the ground, a full communications programme in conjunction with Westminster City Council’s Communications Team was set up. The team launched an awareness campaign, including information on site, social media releases and media relations. MARKETING CAMPAIGN

SIGNAGE To highlight the benefits of the scheme, branded POS was displayed on site. These included:

• Banners

• Courtesy Boards

• Information Postcards

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PRESS RELEASES A joint press release between FM Conway and Westminster was prepared by the Westminster City Council Communications Team and distributed to several major news outlets. This was then distributed across relevant industry trade titles and clients from both parties.

WESTMINSTER’S GROUND-BREAKING LOW-CARBON ROADWORKS Westminster City Council and FM Conway break ground on first of its kind low-carbon construction scheme, revolutionising the way public realm projects are designed and delivered in the centre of London. A six-week project to repair public highways and upgrade the footway in King St in the heart of Westminster will see the exclusive use of electric vehicles, tools, welfare, and recycled equipment, to remove the traditional need for diesel and petrol engines and cut carbon emissions by almost 75% compared to traditional industry methods. • Electric JCB excavators and ground tools • Electric ZipCar for carbon-free transport to and from site • ‘GreenPatch’, an FM Conway recycled asphalt product • Quieter electric equipment will reduce noise pollution to local residents • EV charging points for electric vehicles and tools which will remain in situ for local residents as a legacy of this project • Ecargo bike for small deliveries As a local authority set at the heart of London, Westminster Council delivers approximately £50m worth of public realm repair and rejuvenation projects each year, however, their latest collaboration with contractors FM Conway aims to deliver a ground- breaking change, not only for Westminster, but for the future of the industry. Spearheading this new form of sustainable construction is a key priority for Westminster and FM Conway, who have both set out ambitious targets to achieve carbon neutrality ahead of the Government’s target of 2050. Further measures will include the use of:

Cllr Andrew Smith, Westminster’s Cabinet Member for Highways & Environment: “If we are to truly tackle the effects of climate change and meet our ambitious target of Westminster being carbon neutral by 2030, then we must revolutionise the way we do things as a local authority, this includes the way we carry out our essential daily works and operations.” This scheme is not only ground-breaking but also a catalyst for change in the way we do things. We hope that the success of this trial will see public realm works across the city transform for the better and help us towards maintaining a greener and cleaner Westminster.” “It is fantastic to see this great partnership taking such an important step forward in our ambition to tackle carbon emissions. “As an industry leader for driving innovation and change, it is vital that our collaborative efforts are seen as the foundation for transforming our working practices for the better. We all have a responsibility to protect our planet and with the support of our supply chain, we hope to deliver a low carbon legacy for Westminster and London.” Data collected throughout the trial will be used to calculate the total carbon savings, with the hope that the results can be used to transform how highways and public realms work are carried out in the city. Reducing emissions, noise pollution, road conjunction, and ultimately providing a blueprint for all future works to be low-carbon, low-emission, and sustainable. Adam Green, CEO of FM Conway:

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SOCIAL MEDIA CAMPAIGN A bank of social media posts were prepared by the FM Conway Marketing Team and approved by Westminster City Council’s Communication Team. These were scheduled up to be posted before, during and after the project in order to promote and raise awareness, focusing on the low carbon nature of the trial.

HIGHWAYS UK FIRESIDE CHAT FM Conway secured a speaker slot at the annual Highways UK exhibition. Due to COVID-19, the event was hosted virtually over 3 days, with the first day focussing on carbon and sponsored by FM Conway. The speaker session was led by Vanessa Hilton, FM Conway Head of Carbon and Environment and featured an in-depth discussion on the low carbon trial with Ivan Farrell, FM Conway Performance Manager and Dan Perks, Westminster City Council’s Operations Manager.

WORKING BETTER TOGETHER: SHAPING ZERO CARBON FM Conway hosted an event for their key supply chain to discuss the challenges around the journey to net zero. Phil Robson, Head of Operations as Westminster City Council, attended the event to discuss the low carbon trial and Westminster’s ambitions for net zero. The event was designed to encourage the supply chain to provide further solutions to the current carbon challenge and the results of the problems identified in this low carbon trial.

AWARDS SUBMISSIONS Due to the pioneering nature of the scheme, submissions were sent to the following: • New London Architecture (NLA) showcasing Zero Carbon London case studies under the Public Realm, Infrastructure and Transport projects category

• Chartered Institute Highways & Transportation (CIHT) Awards - Climate Change category

• Construction News Award – Low Carbon Project of the Year

• Highways Magazine Awards - Award for Environmental Sustainability in the Highways Sector

SCHEME PUBLIC LIAISON OFFICER FM Conway’s Robert Burton was engaged as the Public Liaison Officer for the duration of the project. He visited all the premises in the street prior to the works, publicising the works and advising the public on the benefits. He was also available on site every day and received positive feedback from several of the businesses.

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The carbon results have been split down into the operational carbon, which is under FM Conway control and the embodied carbon, which is built into the materials through their manufacture and transportation. RESULTS

OPERATIONAL CARBON RECORDING The site supervisor recorded all carbon producing elements of the operational impact of works daily (See Appendices 3 and 4). This included:

• Travel to site for all staff and visitors

• Vehicle movements including all deliveries to site

• Time spent on power tools and machinery

• Time generator in use on Welfare Unit

The information was taken from the daily sheets and transposed onto a spreadsheet. The total mileage for travel and vehicle movements, and the hours spent on operational tools was calculated. The carbon was then calculated by multiplying these figures against the appropriate carbon values contained within the Government’s conversion factor document and divided by 1000 to give a carbon cost per tonne figure (TCO2e):

Total Miles Travelled/Total Hours Spent x Item Conversion Factor 1000 The results were independently verified by Norman Rourke Pryme Ltd (NRP) and Metis Ltd

CARBON SAVINGS The operations on King Street saved 4.21t of carbon against the Marlborough Hill scheme. This is equal to 71% saving. When this is averaged out per day, the saving that the new method produces is 79% . If these methods were to be implemented across the whole PPM footway programme, over 100t of carbon could be reduced, which would equate to a lorry travelling around the M25 38 times. The prohibition of diesel from site was the primary factor in these savings, which can be seen when the total carbon figures are broken down into:

• Travel

• Deliveries

• Operation

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The carbon for operations was negligible at just 0.02t for the whole scheme, which was because all the plant was electric.

Travel also saw a large reduction of over 70% as all staff and visitors could only come to site by walking or cycling if they were close, public transport or electric vehicles.

Whereas the deliveries accounted for 1.23t which was a 60% saving against Marlborough Hill since most vehicles were fuelled by HVO instead of diesel. However, we have still assumed that HVO has a carbon footprint 50% of diesel.

The total carbon used on both King Street and Marlborough Hill is shown in the table on page 35:

Figure 12 - Graph Showing the Comparison of Operational Carbon Produced on King Street & Marlborough Hill

KING ST V MARLBOROUGH HILL OPERATIONAL CARBON PRODUCED BY TONNAGE

7

6

5

4

3

2

1

0

Total

Travel

Deliveries

Operations

Marlborough Hill

King Street

The above graph shows the total carbon savings made on King Street compared to Marlborough Hill. The breakdown shows 76% saving on travel (0.01t per day), 60% on deliveries (0.03t per day), 97% saving on operations (0.0005t per day).

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Figure 13 - Pie Charts Showing the Carbon Produced by Type Across Both Schemes

MARLBOROUGH HILL OPERATIONAL CARBON

KING STREET OPERATIONAL CARBON

12.90%

35.40%

1.1%

28.1%

51.70%

70.8%

Travel

Deliveries Operations

Travel

Deliveries Operations

The above pie charts show that the operational carbon using electric plant is just over 1% of the total. The deliveries have increased to over 70% of the total and shows where the next concentration of effort needs to go. HVO fuel is only an interim measure and this percentage will come down when larger vehicles are able to convert to electric.

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Figure 14 - Graph Showing the Carbon Breakdown Across All Operations

INDIVIDUAL CARBON ELEMENTS

2.5

2

1.5

1

0.5

0

Vehicle - Grab

Vehicle - Lorry

Plant - Excavator

Travel - Ops

Travel - Sup

Vehicle - External

Plant - Wacker

Plant - Saw

Plant - Welfare

Marlborough Hill

King Street

Carbon Saving

This graph shows a further breakdown of the carbon for travel, delivery and operations. Note that if an electric grab lorry could be utilised it would represent another significant saving.

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EMBODIED CARBON

Metis Ltd have developed a tool specific to the Westminster contract that calculates the embodied carbon contained within the materials used on the contract. This includes manufacture and delivery but it does not include the carbon involved in installing the materials. The tool works by calculating the carbon per schedule of rate item and multiplying it by the quantities. From the final measures on site the tool calculated that the carbon in the Marlborough Hill materials amounted to 40.69t and the King Street items came to 17.93t. That is a saving of 56% scheme on scheme. When we consider the square meterage, it is 0.13t on Marlborough Hill and 0.07t on King Street, a still impressive 46% saving per m². These savings were made with a small tweak to the design in having a slightly thinner slab, a shallower foundation, and a slightly lower concrete.

The graph below shows the difference in embodied carbon between the two schemes.

Figure 15 - Bar Chart Showing the Total Carbon Footprint at both sites

INDIVIDUAL CARBON ELEMENTS

45

40

35

30

25

20

15

10

5

0

Marlborough Hill

King Street

The tool can show the carbon breakdown per item. The graph below shows the total carbon outputs per series number from the Specification for Highway Works.

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Figure 16 - Graph showing how the embodied carbon is broken down

BREAKDOWN OF EMBODIED CARBON BY WORKS TYPE

50

45

40

35

30

25

20

15

10

5

0

Site Clearance

Structural Concrete

Fencing

Earthworks

Paving

Marlborough Hill

King Street

This demonstrates that cementitious products are the biggest producers of carbon within highways works and that if carbon is considered at the outset of the scheme, there are opportunities to introduce lower carbon options at the early design stages.

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OVERALL CARBON USAGE

Figure 17 and Figure 18 demonstrate the overall carbon usage for both schemes and the savings made at King Street. They illustrate that the biggest carbon savings are to be made by changing the materials used on the highway. Exploration of recycled and lower carbon products will increase the embodied carbon savings. The operational carbon showed the biggest percentage saving against the comparison site, as the elimination of diesel reduced it to as low a footprint as possible at this stage. Once all vehicles and plant are able to be powered by sustainable fuels the operational carbon will be carbon neutral.

Figure 17 - Table showing the whole tCO2e carbon footprint for both schemes:

Marlborough Hill

King Street

Duration on site (Days)

31

40

Distance travelled, inc labour, supervision & deliveries (Miles) Plant usage, inc welfare (Hours) Operational carbon footprint (KgCO2e) Average operational carbon footprint per day Embodied material carbon footprint (KgCO2e)

7540

9394

71.5

114.8

5.95t

1.74t

0.19t

0.04t

40.69t

17.93t

Embodied carbon per m2 Total carbon footprint Carbon footprint per m2

0.13t

0.07t 19.67t 0.07t

46.64t

0.15t

Figure 18 - Table showing the King Street carbon savings

Tonnes Saved

Percentage Saving

Total operational carbon saving against comparison site Operational carbon savings per day Total Embodied carbon saving against comparison site Embodied carbon savings per m2 Total carbon savings against comparison site Total carbon savings per m2

4.21t

71%

0.15t

79%

22.76t

56%

0.06t

46%

26.97t

58%

0.08t

53%

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OTHER ENVIRONMENTAL BENEFITS

NOISE MONITORING Socotec were commissioned to deliver background noise and construction noise monitoring for Marlborough Hill and King Street. Additional testing on each piece of equipment was carried out to give a better understanding of the individual items contributing to the overall noise levels. The results are below:

DISC CUTTER

Petrol (dB)

Electric (dB)

Running Idle at Source Running Idle 3M away

102.6 88.0

84.2 81.7 101.4 87.8

In Use at Source In Use 3M Away

106

92.4

WACKER PLATE

Petrol (dB)

Electric (dB)

Running Idle at Source Running Idle 3M away

106.1

98.2 86.1 100 85.9

91.1

In Use at Source In Use 3M Away

103.4

92.7

MINI DIGGER

Diesel (dB)

Electric (dB)

Running Idle at Source Running Idle 3M away In Use at Source (Concrete breakout) In Use 3M Away (Concrete breakout)

88.7 77.2

68.4 62.7

107.9

107.2

91.5

99.2

The ‘Running Idle at Source’ figures show how much quieter electric plant is compared to diesel. In addition to the above plant, the electric and solar welfare made no additional noise to the ambient noise. King Street ambient noise is marginally higher than at Marlborough Hill and subject to inconsistent very loud noises such as helicopters, vans and motorbikes. The minimum sound recorded was 6dbA higher at King Street than at Marlborough Hill which indicates a consistent higher output background noise.

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