TOWN AND COUNTRY PLANNING ACT 1990, as amended

SECTION 78

THE TOWN & COUNTRY PLANNING (INQUIRIES PROCEDURE) (ENGLAND) RULES 2000

PROOF OF EVIDENCE OF JOHN MACAULAY BEng (Hons) CEng MICE APPENDICES

APPELLANT/S: Pinewood Studios Ltd.

AGENT: DTZ

APPEAL SITE: Site at land identified for Project Pinewood adjacent to Pinewood Studios, Pinewood Road, Iver Heath; Denham Road/Sevenhills Road Junction and Five Points Roundabout

DEVELOPMENT: Living and working community for the creative industries with associated highway improvements

L.P.A. REFERENCE: 09/00706/OUT; 09/00707/FUL and 9/00708/FUL.

INSPECTORATE REFERENCE: APP/N0410/A/10/2126663; APP/N0410/A/2126665 and APP/N0410/A/2126667

February 2011

APPENDICES

A Trip Forecasts Review Technical Note B Supplementary Safety Audit (Five Points and Seven Hills Road application schemes) C Designer’s Response to Five Points Audit only D Five Points Technical Note E Proposed A412 Road Safety Package F Proposed ITS Package G Proposed Traffic Calming and Environment Enhancement Package H Proposed Wider Bus Package I Extracts from TA 79/99 Traffic capacity of Urban Roads

Appendix A Trip Forecasts Review Technical Note

Pinewood Studios Inquiry Appendix A: Trip Forecasts Review

Introduction

During pre-application discussions the base line traffic generation figures from the existing Pinewood site and those forecast from the existing Masterplan planning consent were not examined in great depth. The reasons for this were essentially that these figures had been recently tested during consideration of the Masterplan application. Consequently, these were taken at face value and the available time was therefore focussed on consideration of the trip forecasts associated with the current Project Pinewood application. However, as a part of developing an evidence base for the impending inquiry, this work has been revisited the purpose of this note is therefore to undertake a ‘health check’ on the scale of trip forecast increases contained within the TA against the predicted increase in employment. Reference is also made to the existing and proposed parking provision.

Existing Pinewood Site

The existing Pinewood Film and Television Studios currently comprises 101,580m2 of office, workshops, studio and sound stage, post production and ancillary uses (Supplementary Technical Report: Stuart Michael Associates June 2004).

The December 2008 Travel Survey, appended to the Transport Assessment (May 2009) presents the existing staff numbers on site as follows;

 150 permanent staff

 50 contract staff

 750 tenant staff

 950 total staff

The Travel Survey, or Transport Assessment, does not mention Production Companies staff.

1

In Document 5: Economic Impact Assessment (May 2009) paragraph 3.3 refers to the:-

 200 employees

 750 tenant staff

 800-1800 production companies staff

 1750-2750 total staff

Therefore, in terms of the existing site, the potential number of employees on site can range from 1,750 to 2,750 staff.

The existing level of parking provision is understood to be 1,528 spaces (1 space per 66m2 GFA)

Predicted Impact of Consented Masterplan

The consented Masterplan was for a total development area of 67,260m2 (Supplementary Technical Report: Stuart Michael Associates June 2004). The level of parking provision for the Masterplan, including the existing site, is understood to be based on the existing ratio, and totals 2,306 spaces for the existing and Masterplan site (S106 Schedule 3: Details of Travel Plan March 22nd 2006).

The employment figures for the consented Masterplan are presented in paragraph 3.6 of Document 5, which refers to a figure of 1,500 jobs.

The number of employees on site, including the Masterplan, therefore ranges from 3,250 to 4,250 staff (based on the range quoted within Document 5).

If we compare the predicted growth in Employment, as a result of the Masterplan, the ranges are as shown in Table 1 below;

Table 1: Predicted Increase in Employees associated with Masterplan

Pinewood + Pinewood - Existing Percentage Scenario Masterplan 2008 Increase 2014

High 1,750 3,250 85%

Mid 2,250 3,750 66%

Low 2,750 4,250 55%

2

The predicted increase in traffic assumed for the Masterplan within the TA is as shown in Tables 2 and 3 below. It should be noted that this review is based on the existing arrivals and departures as contained within the TA, however the number of employees on site at the time of the survey, and the extent to which this represents a typical day, is not known.

Table 2: AM Peak Predicted Increase in Traffic associated with Masterplan

Pinewood + Pinewood + Pinewood - Masterplan Masterplan Percentage Scenario Existing 2014 2014 Difference 2008 (Transport (Based on Assessment) Employment)

High 641 968 1,185 22%

Mid 641 968 1,064 10%

Low 641 968 994 3%

Table 3: PM Peak Predicted Increase in Traffic associated with Masterplan

Pinewood + Pinewood + Pinewood - Masterplan Masterplan Percentage Scenario Existing 2014 2014 Difference 2008 (Transport (Based on Assessment) Employment) High 681 995 1,260 27%

Mid 681 995 1,130 14%

Low 681 995 1,055 6%

The above comparison shows that the volume of traffic associated with the Masterplan is potentially significantly underestimated within the TA, by up to 27%. This would emphasise the need to consider a range in traffic forecasts.

Predicted Impact of Project Pinewood

It is understood Project Pinewood seeks permission for an additional 47,840 m2 GFA, bringing the total built environment to 175,080 m2 GFA.

In terms of car parking, the total level of parking provision for the existing site, the Masterplan and Project Pinewood site is 4,506 spaces.

3

Although it is accepted that the trip rates associated with the residential elements are based on reasonable sources, the residential trips do however include the assumption that 20% of residents will work on site. It is not know the source of this assumption. In addition, a further 10% reduction has also been applied for the CTP. For the purpose of considering the potential range of trips, this assessment comprises;

 the forecasts assumed within the TA;

 the total residential trips without a reduction, and

 a mid point between the two values for high, low and mid forecasts respectively.

The site uses associated with the film and television related uses total 11,000m2 GFA. The level of permanent employment associated with Project Pinewood is quoted as 628 to 728 permanent staff. The level of construction staff ranges from 431 to 544 over a 10 year period, with an additional 104 staff associated with the streetscapes Document 5: Economic Impact Assessment (May 2009) Para 3.16 & Table 3.2). The level of employment on Project Pinewood therefore ranges from 1,163 to 1,376.

Table 4: Predicted Increase in Employees associated with Masterplan & Project Pinewood

Pinewood + Pinewood + Pinewood Masterplan + Percentage Scenario Masterplan Project Pinewood Increase Existing 2008 2014 2022 High 1,750 3,250 4,413 152%

Mid 2,250 3,750 5,020 123%

Low 2,750 4,250 5,626 105%

If the above percentages of increase in employees are applied to the existing traffic volumes accessing the site (on the basis that the uses are broadly similar), the future year traffic flows would be as shown in Tables 5 and 6:

4

Table 5: AM Peak Potential Increase in Traffic (2022)

Total Pinewood Residential Total Traffic Percentage Scenario Employment Increase Existing 2008 Traffic 2022 Traffic 2022 2022

High 641 1,615 910 2,525 294%

Mid 641 1,430 780 2,210 245%

Low 641 1,314 649 1,963 206%

Table 6: PM Peak Potential Increase in Traffic (2022)

Total Pinewood Residential Total Traffic Percentage Scenario Employment Increase Existing 2008 Traffic 2022 Traffic 2022 2022

High 681 1,711 840 2,551 275%

Mid 681 1,514 792 2,306 239%

Low 681 1,392 743 2,135 215%

The above potential range of traffic forecasts can then be compared against those contained within the TA, as shown in Table 7 below;

Table 7: AM & PM Comparison of Potential Traffic against TA Forecasts (2022)

AM Peak PM Peak

Scenario Potential Potential TA Traffic Percentage TA Traffic Percentage Traffic Traffic Forecast* Forecasts* Difference Forecast Difference Forecast

High 2,525 1,893 33% 2,551 1,962 30%

Mid 2,210 1,893 17% 2,306 1,962 18%

Low 1,963 1,893 4% 2,135 1,962 9%

5

Summary

The purpose of this note is to consider the potential range of trip forecasts, based on the employment forecasts, and compare this range to the forecasts used within the TA. The basis of the review is the projected increases in employment, and is based on the figures quoted within the following documents;

 Supplementary Technical Report: Stuart Michael Associates June 2004;

 Project Pinewood Transport Assessment: Arup May 2009; and

 Document 5: Economic Impact Assessment: DTZ May 2009.

The assessment demonstrates the difficulty in estimating the likely trip generation of the site, and the potential range of trips which could occur. As shown, the potential traffic generation could be up to 33% higher than that assumed within the operational assessments.

This demonstrates that, given the broad range of potential trips and uncertainty over the frequency to which the trips assumed within the TA could be exceeded, sensitivity tests which consider the impact of a range of trip forecasts need to be assessed.

6

Appendix A – Summary of Project Pinewood Trip Generation (Transport Assessment: Arup May 2009 – Section 6.5)

AM Peak PM Peak Land Use Comment Arrivals Departures Total Arrivals Departures Total

Rates based on combination of Pinewood Green Estate & Trewarden Residential 85 564 649 456 287 743 Avenue Estate. A reduction based on internalisation of trips and the CTP has been applied.

Rates based on assumed employment Creative Industries 108 0 108 0 79 79 density and travel to works surveys.

Screen Crafts Academy 51 13 65 11 16 28 Rates based on TRICS database.

Community Uses Rates based on TRICS database. - Multipurpose 8 3 11 14 8 22

7

Facility 5 2 7 2 3 5 - Adult Training Centre 0 0 0 0 0 0 - Pre and Primary School 0 0 0 0 0 0 - Retail

The TA assumes number of staff on site Productions 28 0 28 0 21 21 limited to 10%.

Total 285 582 867 483 414 897

8

Appendix B Supplementary Safety Audit (Five Points and Seven Hills Road application schemes)

Buckinghamshire County Council

Pinewood Studios

Supplementary Road Safety Audit Stage 1

November 2010

Document Number: B1279808/ Pinewood/FP & SHR/RSA1+/01

Revision: 01

Jacobs, Tower Bridge Court, 226 Tower Bridge Road, London SE1 2UP Tel No: 020 7378 2884 Fax No :020 7939 1418

Document control sheet BPP 04 F8

Client: Buckinghamshire County Council Job No B1279808 Project: Pinewood Studios Doc No: Pinewood/FP &SHR/RSA1+/01 Document Title: Road Safety Audit Stage 1 Revision: 01

Originator Checked by Reviewed by Approved by

ORIGINAL NAME NAME NAME NAME John McCormick Caroline Nash Kate Carpenter Kate Carpenter DATE SIGNATURE SIGNATURE SIGNATURE SIGNATURE 19/11/2010

Document Status: For Client Comment

REVISION NAME NAME NAME NAME

DATE SIGNATURE SIGNATURE SIGNATURE SIGNATURE

Document Status

REVISION NAME NAME NAME NAME

DATE SIGNATURE SIGNATURE SIGNATURE SIGNATURE

Document Status

REVISION NAME NAME NAME NAME

DATE SIGNATURE SIGNATURE SIGNATURE SIGNATURE

Document Status

Jacobs Engineering U.K. Limited

This document has been prepared by a division, subsidiary or affiliate of Jacobs Engineering U.K. Limited (“Jacobs”) in its professional capacity as consultants in accordance with the terms and conditions of Jacobs’ contract with the commissioning party (the “Client”). Regard should be had to those terms and conditions when considering and/or placing any reliance on this document. No part of this document may be copied or reproduced by any means without prior written permission from Jacobs. If you have received this document in error, please destroy all copies in your possession or control and notify Jacobs.

Any advice, opinions, or recommendations within this document (a) should be read and relied upon only in the context of the document as a whole; (b) do not, in any way, purport to include any manner of legal advice or opinion; (c) are based upon the information made available to Jacobs at the date of this document and on current UK standards, codes, technology and construction practices as at the date of this document. It should be noted and it is expressly stated that no independent verification of any of the documents or information supplied to Jacobs has been made. No liability is accepted by Jacobs for any use of this document, other than for the purposes for which it was originally prepared and provided. Following final delivery of this document to the Client, Jacobs will have no further obligations or duty to advise the Client on any matters, including development affecting the information or advice provided in this document.

This document has been prepared for the exclusive use of the Client and unless otherwise agreed in writing by Jacobs, no other party may use, make use of or rely on the contents of this document. Should the Client wish to release this document to a third party, Jacobs may, at its discretion, agree to such release provided that (a) Jacobs’ written agreement is obtained prior to such release; and (b) by release of the document to the third party, that third party does not acquire any rights, contractual or otherwise, whatsoever against Jacobs and Jacobs, accordingly, assume no duties, liabilities or obligations to that third party; and (c) Jacobs accepts no responsibility for any loss or damage incurred by the Client or for any conflict of Jacobs’ interests arising out of the Client's release of this document to the third party.

Contents

1 Introduction 1 1.1 Commissioning and Scope 1 1.2 Scheme Description 1 1.3 Progress of Scheme Design 1 1.4 Supplementary Road Safety Audit Stage 1 1

2 Five Points Roundabout 3

Original Issues Raised by Arup 2.1 FP1 – Loss of Parking 3 2.2 FP2 – Existing Sign Next to Footway Too Low 4 2.3 FP3 – Visibility at Pub Access 5 2.4 FP4 – Visibility Lines Crossing Land Outside Highway Boundaries 6 2.5 FP5 – Incorrect Use of Right Turn Arrow 6 2.6 FP6 – Poor Forward Visibility of Signals 7 2.7 FP7 – Existing Bus Stop on Corner 8 2.8 FP8 – Forward Visibility of Signals 9 2.9 FP9 – Forward Visibility of Signals on Slough Road 10 2.10 FP10 – ‘See-through’ of Pedestrian Signals 10 2.11 FP11 – Pedestrians Crossing to the Central Island 11 2.12 FP12 – Access off Wood Lane Appears Closed 12 2.13 FP13 – Visibility Lines Crossing Land Outside Highway Boundaries 13 2.14 FP14 – Service Lay-bys Obstructing Visibility of Signals 13 2.15 FP15 – Location of Crossing of Bus Lane 14 2.16 FP16 – Incorrect Use of Tactile Paving 14 2.17 FP17 – Location of Secondary Signal Heads 15 2.18 FP18 – Corner Visibility Passing Outside Highway Limited and Over Maintenance Lay-bys 15 2.19 FP19 – Clashes Between Swept Paths of Vehicles 16

Additional Issues Raised by Jacobs 2.20 FP20 – Traffic Island in Wood Lane 17 2.21 FP21 – Possible Obstruction of Pedestrian Route 18 2.22 FP22 – ‘See-through’ on Slough Road Approach 19 2.23 FP23 – Slough Road Resident Parking 20 2.24 FP24 – Traffic Signal Stacking Lengths 21 2.25 FP25 – Church Road approach 21 2.26 FP26 – Accesses on Church Road 21 2.27 FP27 – Pedestrian Crossing on Northbound Exit of Church Road 22 2.28 FP28 – Kerb Alignment Protrudes into Circulatory Carriageway 22 2.29 FP29 – No Provision Made for Vehicular Access to Substation 22

2.30 FP30 – Narrowed Central Reservation May Not Be Sufficient to Accommodate the Working Width of Road Restraint System 23 2.31 FP31 – Possibility of ‘See-through’ Between Bus Gate and Stop Line at Circulatory 23 2.32 FP32 – Existing Pedestrian Access Route Severed by Proposed Scheme 24

3 Seven Hills Road Junction 25

Original Issues Raised by Arup 3.1 SHR1 – No Allowance for Access 25 3.2 SHR2 – Poor Visibility of Roundabout from the North 25 3.3 SHR3 – Insufficient Northbound Deflection 26 3.4 SHR4 – Too Sharp an Entry Angle from the South 27 3.5 SHR5 – Insufficient Circulatory Width 27 3.6 SHR6 – Poor Visibility to Right from Round Coppice 29

Additional Issues Raised by Jacobs 3.7 SHR7 – Confusing Signals for Vehicles Emerging from Round Coppice 30 3.8 SHR8 – Confusing Signals for Vehicles Exiting the Roundabout Southbound 30

4 Audit Team Statement 31

5 Supplementary Road Safety Audit Exception Response 32

6 Other Issues 35 6.1 Non-Motorised Users 35 6.2 Predicted Traffic Flows 35 6.3 Street Lighting 35

7 Summary 36 7.1 General 36 7.2 Five Points Roundabout 36 7.3 Seven Hills Road Junction 36

Appendix A Documents Used Appendix B Items Considered Appendix C Problem Location Plans

1 Introduction

1.1 Commissioning and Scope

This report results from a Stage 1 Road Safety Audit carried out on the proposed works at Five Points Roundabout and at the A412 Denham Road/ Seven Hills Road junction at the request of Dave Green of Jacobs.

1.2 Scheme Description

1.2.1 Pinewood Development

Pinewood Studios Limited are planning to extend their existing site, adjacent to Iver Heath, with around 1400 residential units. As part of these plans upgrades to the existing local highway network are required and are being designed by Arup. The overall highway improvements comprise the redevelopment of the Five Points roundabout into an elongated signal-controlled junction, along with four roundabout junctions and road widening.

This report only covers the proposals for Five Points Roundabout and the A412 Denham Road/Seven Hills Road junction.

1.2.2 Five Points Roundabout

Five Points is a large, 5-leg roundabout forming the junction of the A412, A4007, Wood Lane and Pinewood Road. The proposed design expands the current junction into a multi-lane, signal-controlled, elongated roundabout, with new pedestrian crossing facilities and a bus link through the central island.

1.2.3 Seven Hills Road Junction

The existing junction is a single-carriageway T-junction between Seven Hills Road and A412 Denham Road. The proposed design changes involve altering the junction into a roundabout with two-lane entries on Denham Road.

1.3 Progress of Scheme Design

At this time, preliminary designs of the Five Points and Seven Hills Road junctions have been produced by Arup. These proposals have been audited by Arup and the recommendations made have been responded to by the design team. The designs have not yet been modified to reflect these responses.

1.4 Supplementary Road Safety Audit Stage 1

1.4.1 Terms of Reference

The terms of reference of this Supplementary Road Safety Audit are as described in HD 19/03. The team has examined and reported only on the road safety implications of the scheme as presented and has not examined or verified the compliance of the designs to any other criteria.

1.4.2 Audit Team and Programme

The audit team Kate Carpenter BEng CEng MICE FCIHT, Technical Director Caroline Nash BEng CEng MICE, Principal Road Safety Engineer Jacobs, Tower Bridge Office Audit Observers None Documents Used: References in this report to the proposal drawings refer to these drawings:
FP-7000 (Arup, revision 02)
SRA-7000 (Arup, revision 02) The following documents were also used:
A412 Denham Road/Seven Hills Road Roundabout Stage 1 Road Safety Audit (Arup, doc ref.: 09/7492)
Five Points Roundabout Stage 1 Road Safety Audit (Arup, doc ref.: 09/7491)
Pinewood Stage 1 Road Safety Audit – Designer’s Response (Arup, doc ref. n/a)
Transportation Statement to the Planning Inspectorate at Buckinghamshire County Council in respect of the future appeals regarding Planning Applications 09/00706, 07&08 for proposed development at Pinewood Studios (Buckinghamshire County Council, doc ref. n/a) Desktop evaluation Location: Jacobs Tower Bridge Office Date: 01/11/2010 & 02/11/2010 Daylight site visit. Site visited by: Kate Carpenter and Date: 03/11/2010 Caroline Nash Time: Five Points Weather: Cloudy but dry Roundabout - 10:00 – 12:00, Seven Hills Traffic: Five Points Roundabout – junction - 12:00 – moderate, Seven Hills junction – 13:00 moderate Site visit during the A site visit during the hours of darkness is not required at this hours of darkness. stage.

Each of the auditors’ responses is classified as a 'Problem' that is likely to result in a significant road safety hazard.

Where recommendations are made these do not comprise design decisions, and it remains the responsibility of the design team to incorporate any changes into the scheme, and consider any interactions between design elements.

2 Five Points Roundabout

Original Issues Raised by Arup

The proposals were subject to a Stage 1 Road Safety Audit carried out in February 2009 by Mr R Thomas and Mr C van Lottum. The following items were raised in that report. The designer’s response and the Jacobs audit team comments are also shown.

2.1 FP1 – Loss of Parking

2.1.1 Problem

A bus lane is provided along the eastbound lane of the A412. No indication is given as to where this starts. There is residential access required along the side of the bus lane, and resident parking occurs on the existing footway and verge in this area. This could result in local access being obtained by driving along the bus lane, which could indicate to other drivers that the bus lane is not full-time, leading to its use to jump queues. There is also a risk that local inhabitants could park within the bus lane causing buses to pull back out into traffic leading to collisions.

2.1.2 Recommendation

Ensure the bus lane is adequately signed to make its function clear to drivers.

2.1.3 Designer’s Response

Design Team agrees with recommendation. Appropriate signage for the bus lane will be developed, in discussion with the highway authority, during the detailed design stage.

2.1.4 Supplementary Stage 1 RSA Comments

We agree with the issue raised and the recommendation and also recommend that the Police are requested to provide relevant enforcement.

2.2 FP2 – Existing Sign Next to Footway Too Low

2.2.1 Problem

There is an existing direction sign on the A412 to the east of the existing roundabout which is located close to the eastbound [northern] footway. The sign face is less than 1.6m high [it is assumed that this refers to the mounting height] and could be collided with by a pedestrian walking near the back of the footway.

2.2.2 Recommendation

Raise the level of the sign to where it is no longer a risk to pedestrians.

2.2.3 Designer’s Response

Design Team agrees with recommendation. The positioning of the sign will be assessed as part of the overall signage strategy, in discussion with the highway authority, during the detailed design stage.

2.2.4 Supplementary Stage 1 RSA Comments

The audit team did not have a plan showing the location of this sign and could not identify it while on site.

2.3 FP3 – Visibility at Pub Access

2.3.1 Problem

The A412 Uxbridge Road leading to the west from the Five Points Roundabout is currently hatched out on the inside to direct drivers to the outer lane (see Figure 1, below). The reason for this is not known but the audit team speculates that this is to serve a visibility problem on for drivers entering and emerging from the access at the Crooked Billet public house and the houses and garage beyond. The westbound lane of Uxbridge Road is narrowed by setting the central reserve to the south to enable the provision of an eastbound bus lane. This will push traffic emerging from the roundabout to the left and will reduce visibility of these vehicles from the public house access, increasing the risk of collisions.

2.3.2 Recommendation

Increase visibility to the right for vehicles emerging from the public house.

2.3.3 Designer’s Response

Design Team agrees with recommendation. However, following discussions with the highway authority it is expected that two full westbound lanes on the Uxbridge Road exit will be necessary to accommodate the forecast flows for the design year of 2022. Therefore, the detailed design will need to address this, together with visibility for the accesses to the public house, properties and garage.

2.3.4 Supplementary Stage 1 RSA Comments

We agree with the issue raised and note that the Design Team suggest two west- bound lanes are needed, whilst the current proposal only shows a single lane.

Figure 1 – Crooked Billet public house access on A412 Uxbridge Road

2.4 FP4 – Visibility Lines Crossing Land Outside Highway Boundaries

2.4.1 Problem

The stopping sight distance line for the turn to Pinewood Road off A412 Uxbridge Road is shown for 60kph at 90m. This crosses outside the highway boundary. The distance shown for 60kph may not reflect the actual 85%ile vehicle speeds on the dual carriageway approach to the roundabout. As there is no control of what happens outside the highway boundary, it would appear that the distance shown does not reflect the actual distance available. There is a risk of heavy braking and loss of control.

2.4.2 Recommendation

Ensure the forward visibility is not obstructed.

2.4.3 Designer’s Response

Design Team agrees with the recommendation. However, as the applicant has no control over the land beyond the highway boundary in this location, the available SSD is limited. A further review of the SSD shown on Drawing FP-7901 indicates that without encroaching outside the highway boundary the available SSD for the turn in question is approximately 70m. This equates to “one step below the desirable minimum” for 60kph as set out in TD 9/93. The Design Team proposed that the issue of design speeds and relaxations are reviewed with the highway authority. In addition, appropriate signage and road markings will be developed in discussion with the highway authority, during the detailed design stage.

2.4.4 Supplementary Stage 1 RSA Comments

The audit team were not supplied with drawing FP-7901 or any other documents showing evidence for the selection of the design speed.

The audit team agrees with the issue raised. The speed limit on the Uxbridge Road approach to the existing roundabout is 40mph which equates to a design speed of 70kph. The desirable minimum SSD for a 70kph design speed is 120m, with ‘one step below’ coming to 90m. 70m is equivalent to two steps below the desirable minimum.

2.5 FP5 – Incorrect Use of Right Turn Arrow

2.5.1 Problem

Right-turn arrow markings are indicated on the north side of the gyratory, opposite Pinewood Road. This could lead to confusion and a driver entering the proposed bus link.

2.5.2 Recommendation

Provide straight-ahead road markings in this location.

2.5.3 Designer’s Response

Design Team agrees with recommendation. Straight ahead road markings will be incorporated.

2.5.4 Supplementary Stage 1 RSA Comments

We agree with the problem and Design Team’s revised proposal. The use of lettering for destinations (referred to in item FP24) will be beneficial given that all 3 lanes will now indicate ‘AHEAD ONLY’.

2.6 FP6 – Poor Forward Visibility of Signals

2.6.1 Problem

Traffic signals on the southbound approach to the proposed gyratory are located around a bend. Drawing FP-7901 indicates that the off-side signal can just be seen by an approaching driver, but this may be obstructed by other vehicles and the heavily wooded area behind the verge. There is a risk that approaching drivers would not appreciate the layout ahead, leading to rear-end shunts and over-running of the stop line.

2.6.2 Recommendation

Set back the verge to increase visibility of both signals.

2.6.3 Designer’s Response

Design Team disagrees with recommendation as the applicant has no control over the land beyond the highway boundary in this location and therefore the verge cannot be set back.

However, the Design Team proposes that the issues of design speeds and relaxations are reviewed with the highway authority. In addition, appropriate signage, road markings and landscaping, together with the possibility of using high level signal heads, will be developed in discussion with the highway authority during the detailed design stage.

2.6.4 Supplementary Stage 1 RSA Comments

This audit team were not supplied with drawing FP-7901.

We agree with the problem raised and recognise the constraints. We recommend that the stop line is set back towards the northern corner of the splitter island to improve forward visibility. This would provide good forward visibility of the off-side signal and, provided the near-side verge is managed, good forward visibility of the near-side signal can also be achieved.

2.7 FP7 – Existing Bus Stop on Corner

2.7.1 Problem

There is an existing bus stop on the corner where the westbound traffic on Church Road will be turned to the south-west (see Figure 2, below). There is a risk that drivers may try to overtake the bus and not realise that their route turns to the left, leading to them travelling along the eastbound leg of the road in the wrong direction.

2.7.2 Recommendation

Relocate the bus stop away from the diverge.

2.7.3 Designer’s Response

Design Team agrees with the recommendation. The positioning of the bus stop will be assessed, in discussion with the highway authority, during the detailed design stage.

2.7.4 Supplementary Stage 1 RSA Comments

This bus stop adjacent to the British Legion Club is likely to be used by a significant number of people at certain times. No provision for relocation is shown. Hazards at this location are increased as there are several vehicular accesses in the area which may conflict with potential bus stop locations. It is recommended that all hazards are considered in the design to ensure provision for a safe bus stop location is made.

Figure 2 – Existing bus stop on Church Road

2.8 FP8 – Forward Visibility of Signals

2.8.1 Problem

Traffic signals on the southbound approach to the proposed gyratory are located around a bend. Drawing FP-7902 indicates that the off-side signal can just be seen by an approaching driver, but this may be obstructed by other vehicles and the heavily wooded area behind the verge. There is a risk that approaching drivers would not appreciate the layout ahead, leading to rear end shunts and over-running of the stop line.

2.8.2 Recommendation

Set back the verge to increase visibility of both signal heads.

2.8.3 Designer’s Response

Design Team disagrees with the recommendation as the applicant has no control over the land beyond the highway boundary on the south east side of Church Road until approximately the point at which the nearside kerb diverges from its present alignment and therefore the verge cannot be set back.

However, a further review of the achievable SSD shown on Drawing FP7902 indicates that an SSD of approximately 75m to the nearside is achievable within the highway boundary or land controlled by the applicant. This is greater than the value of 70m specified as “one step below the desirable minimum” for a 60kph design speed in TD 9/93.

The Design Team proposed that the issues of design speeds and relaxations are reviewed with the highway authority. In addition, appropriate signage, road markings and landscaping together with the possibility of using high-level signal heads, will be developed in discussion with the highway authority during the detailed design stage.

2.8.4 Supplementary Stage 1 RSA Comments

This audit team were not supplied with drawing FP-7901 or other documents showing evidence for the selection of the design speed.

The audit team agrees with the issue raised. The speed limit on the Church Road approach to the existing roundabout is 40mph which equates to a design speed of 70kph. The desirable minimum SSD for a 70kph design speed is 120m, with ‘one step below’ coming to 90m.

See also item FP25.

2.9 FP9 – Forward Visibility of Signals on Slough Road

2.9.1 Problem

Traffic signals on the westbound approach to the proposed gyratory are located around a bend. Drawing FP-7902 indicates that the off-side signal can just be seen by an approaching driver, but this may be obstructed by other vehicles and the heavily wooded area behind the verge. There is a risk that approaching drivers would not appreciate the layout ahead, leading to rear end shunts and over-running of the stop line.

2.9.2 Recommendation

Set back the verge to increase visibility of both signal heads.

2.9.3 Designer’s Response

Design Team agrees with recommendation as the verge can be set back within the existing highway boundary or land within the applicant’s control.

2.9.4 Supplementary Stage 1 RSA Comments

The audit team agree with the issue and the recommendation made.

See also item FP22 related to the issue of potential ‘see-through’ over the build out.

2.10 FP10 – ‘See-through’ of Pedestrian Signals

2.10.1 Problem

A pedestrian crossing route is provided between the central gyratory island, across a triangular splitter island, to the south side of the A4007. There is no indication at this stage as to what method of control of pedestrian movements is proposed, but it is noted that this movement is in an almost straight line across two separate carriageways. Depending which type of pedestrian signal is proposed, there is a risk that a pedestrian crossing on road may confuse opposing signal and continue to cross both carriageways.

2.10.2 Recommendation

Provide nearside pedestrian heads only.

2.10.3 Designer’s Response

Design Team agrees with recommendation. The traffic signal equipment/arrangements will be assessed, in discussion with the highway authority, during the detailed design stage.

2.10.4 Supplementary Stage 1 RSA Comments

If these facilities provide for cyclists in the form of Toucan crossings far side indicators would be used and ‘see-through’ would remain a problem.

2.11 FP11 – Pedestrians Crossing to the Central Island

2.11.1 Problem

Pedestrian movements are provided for around the gyratory and between the central gyratory island and Pinewood Road. There is also a link across the central island between Pinewood Road in the north and the A4007. There is a risk that pedestrians travelling between Pinewood Road and Wood Lane to the south would cross directly over the central island and make use of the traffic signal phases to cross the southern side of the gyratory and bus lane, where they could be vulnerable should the signals change.

2.11.2 Recommendation

Provide deterrents to dissuade pedestrians from crossing the central island in this manner. Direction arrows to assist pedestrians in way-finding could also be provided.

2.11.3 Designer’s Response

Design Team agrees with recommendation. The signage and landscaping will be assessed, in discussion with the highway authority, during the detailed design stage.

2.11.4 Supplementary Stage 1 RSA Comments

In addition to the issue raised, a Non-Motorised User appraisal including both pedestrian and cyclist activity should be undertaken in accordance with DMRB HD 42/05. This would help to identify existing and likely future NMU desire lines and appropriate provision in the scheme.

2.12 FP12 – Access off Wood Lane Appears Closed

2.12.1 Problem

A solid edge line is shown across the existing access to the Crooked Billet public House off Wood Road. This is interpreted as indicating that this access is to be closed. As a result, the only access would be left-in/left-out on the A412 Uxbridge Road. The A412 Uxbridge Road is a dual carriageway, and such a closure would lead to long diversions as there are no near-by U-turn facilities. There is a chance that drivers could try to cross the widened grass central reserve beyond the western limit of the central island safety fence, leading to collisions.

2.12.2 Recommendation

Do not close the access to the Crooked Billet of Wood Road.

2.12.3 Designer’s Response

Design Team agrees with recommendation. This is acknowledged to be an error on Drawing FP-7000 as it is not the intention to close this access to the Crooked Billet public house and will be rectified in the next revision of the drawings.

2.12.4 Supplementary Stage 1 RSA Comments

At present the access is at a point where there is one lane in each direction on Wood Lane (see Figure 3, below). The proposals will add one extra northbound lane on the approach to the traffic signals and adjacent to this access. This poses an additional hazard of a driver leaving the car park turning right and failing to register a vehicle in the offside lane possibly concealed by a vehicle in the nearside lane, resulting in collisions. It is recommended that the location of this car park access is reviewed in order to address this problem.

Figure 3 – Existing traffic island on Wood Lane with Crooked Billet PH access in background, on the left

2.13 FP13 – Visibility Lines Crossing Land Outside Highway Boundaries

2.13.1 Problem

An available sight distance from Wood Lane into the A412 Uxbridge Road appears to be 56m. This crosses behind the highway boundary. A vehicle passing through an uninterrupted green phase could be travelling at too rapid a speed to stop at the pedestrian signals on the A412 Uxbridge Road and could collide with a pedestrian.

2.13.2 Recommendation

Link the second phase on the westbound A412 Uxbridge Road to operate only when the phase from Wood Road is on red.

2.13.3 Designer’s Response

Design Team agrees with recommendation. The traffic signal equipment/arrangements will be assessed, in discussion with the highway authority, during the detailed design stage.

2.13.4 Supplementary Stage 1 RSA Comments

We agree with the issue raised and recommendations. In addition we note that the proposed single lane width at the pedestrian crossing appears to be almost 7 metres. This may cause drivers to travel in 2 lanes of traffic resulting in ‘side-swipe’ collisions and may increase the likelihood of drivers failing to see pedestrians at signals.

We would therefore recommend a maximum lane width of 4 metres between the exit of the roundabout to the start of the 2-lane section beyond the petrol filling station.

See item FP32.

2.14 FP14 – Service Lay-bys Obstructing Visibility of Signals

2.14.1 Problem

Two service lay-bys are proposed on the gyratory. They are both located in areas where traffic will be turning, and vehicles parked in the lay-bys will obstruct visibility of signal heads. This could lead to over-running, heavy braking and rear-end shunts, and loss of control.

2.14.2 Recommendation

Relocate the service lay-bys to where visibility of signal heads is not obstructed.

2.14.3 Designer’s Response

Design Team agrees with recommendation. The positioning of these lay-bys will be assessed, in discussion with the highway authority, during the detailed design stage.

2.14.4 Supplementary Stage 1 RSA Comments

In addition to legitimate use by maintenance vehicles, these lay-bys may be used by drivers unsure of their destination as a result of the complex layout of the junction. In

both locations a stationary vehicle will not be aligned parallel to the approaching streams of traffic and the merging manoeuvre necessary on leaving the lay-bys will require drivers to look back to their near-side where visibility is often compromised.

2.15 FP15 – Location of Crossing of Bus Lane

2.15.1 Problem

A dedicated bus lane is proposed in the central island of the gyratory. A pedestrian route crosses this, for which no tactile paving is proposed. Visually impaired pedestrians may not realise they are crossing a length of carriageway and step into the path of a bus. In addition, although it is assumed that the bus would have priority, if a driver needed to stop, it appears the rear of the bus would protrude into the gyratory carriageway where it could be struck by a passing vehicle.

2.15.2 Recommendation

Provide tactile paving at the crossing and locate it further to the south in order that a bus could stop without intruding into the gyratory carriageway.

2.15.3 Designer’s Response

Design Team agrees with recommendation. The position/layout of the tactile paving will be assessed, in discussion with the highway authority, during the detailed design stage.

2.15.4 Supplementary Stage 1 RSA Comments

The audit team agrees with the issue raised and the recommendation. The drawing for this audit does show tactile paving but in an inconsistent way. As stated in the supplementary comments for FP11, the audit team recommends that a Non- Motorised User audit is carried out to assist with the positioning of proposed crossing points and footpath links.

2.16 FP16 – Incorrect Use of Tactile Paving

2.16.1 Problem

Tactile paving has been installed on the traffic islands in accordance with the layout in paragraph 1.5.3.3 of the Guidance on the use of Tactile Paving Surfaces published by the DETR. This refers to triangular islands. The traffic islands are not the small islands shown in the guidance, and pedestrians must walk some considerable distances in place between crossings. They may interpret the crossings as uncontrolled rather than controlled.

2.16.2 Recommendation

Provide L-shaped tactile paving at the crossings.

2.16.3 Designer’s Response

Design Team agrees with recommendation. The position/layout of the tactile paving will be assessed, in discussion with the highway authority, during the detailed design stage.

2.16.4 Supplementary Stage 1 RSA Comments

Consult with local access groups and/or representative bodies for visually impaired users to establish what form of provision, if any, is required at each location.

2.17 FP17 – Location of Secondary Signal Heads

2.17.1 Problem

Many of the secondary crossing heads are located in close proximity to the pedestrian crossings. Where there are multiple lanes, the secondary head may be difficult for some drivers to observe. This could lead to delay in moving off, resulting in rear-end shunt collisions.

2.17.2 Recommendation

Provide additional clearance between the signal heads and the give way lines where possible.

2.17.3 Designer’s Response

Design Team agrees with recommendation. The traffic signal equipment/arrangements will be assessed, in discussion with the highway authority, during the detailed design stage.

2.17.4 Supplementary Stage 1 RSA Comments

It may be appropriate in some locations to install gantry mounted signals if a secondary signal head is difficult to position where it can be seen by drivers in all lanes.

2.18 FP18 – Corner Visibility Passing Outside Highway Limited and Over Maintenance Lay-bys

2.18.1 Problem

Corner visibility is indicated covering areas which are to be kept clear of planting and obstacles. Several sight lines as shown cross either into woodland behind the existing highway limit or across maintenance lay-bys. This could cause forward stopping sight distance to be compromised, leading to rear-end shunt collisions.

2.18.2 Recommendation

Ensure visibility lines are kept clear at all times.

2.18.3 Designer’s Response

Design Team agrees with recommendation. The visibility splays within the highway boundary or land in the applicant’s control will be designed such that they are kept clear of the obstruction, in discussion with the highway authority, during the detailed design stage.

2.18.4 Supplementary Stage 1 RSA Comments

This team supports the comments raised and recognises that there are constraints on available land. We would recommend a structured program of landscape management to keep vegetation trimmed and, at some locations, alteration of the layout may be required to provide acceptable visibility of signals.

See item FP4.

2.19 FP19 – Clashes Between Swept Paths of Vehicles

2.19.1 Problem

There are a number of places where the swept path diagrams indicate clashes between large vehicles. There are other places where the plots indicate a possibility that vehicles over-run into adjacent lanes. This can lead to collisions between vehicles, and sudden breaking with rear-end shunt collisions as a result.

2.19.2 Recommendation

Check the swept path plots and provide appropriate widening.

2.19.3 Designer’s Response

Design Team agrees with recommendation. The Design Team confirms that the vehicle swept paths will be reviewed, in discussion with the highway authority, to ensure that widths are appropriate for the expected movements of larger vehicles.

2.19.4 Supplementary Stage 1 RSA Comments

The swept path drawings were not made available to this audit team.

The circulatory carriageway between the exit and entry of Church Road has a tight radius which may result in turning vehicles overhanging an adjacent vehicle. Although hatched areas are provided to assist large vehicles to turn, this passes through the pedestrian crossing. This may lead pedestrians to stand in the hatched areas, believing it is safe to do so during the red pedestrian phase.

It is recommended that the arrangement is adjusted – if possible - to exclude the hatching proposed.

Additional Issues Raised by Jacobs

The following items have been raised as a result of supplementary Stage 1 Road Safety Audit carried out by Jacobs.

2.20 FP20 – Traffic Island in Wood Lane

2.20.1 Problem

An existing traffic island (see Figure 3, in item 2.12 and Figure 4, below) on Wood Lane south of the access to the Crooked Billet public house is not shown as being removed on drawing no. FP-7000. In order to provide 2 northbound lanes here this island would need to be removed.

2.20.2 Recommendation

The island should be included on design drawings and any safety impacts considered.

Figure 4 – Existing traffic island on Wood lane with evidence of vehicles overrunning nearside kerb

2.21 FP21 – Possible Obstruction of Pedestrian Route

2.21.1 Problem

There are a number of items (cabinets and a mast) of statutory undertakers’ apparatus adjacent to the exit of the roundabout onto Wood Lane. It is possible that some of the apparatus may obstruct the proposed pedestrian route in this location.

2.21.2 Recommendation

Establish the location of all items with respect to the proposed footway to ensure that the pedestrian route is unobstructed.

Figure 5 – Existing statutory undertakers’ cabinets and mast in verge adjacent to Wood Lane exit

2.22 FP22 – ‘See-through’ on Slough Road Approach

2.22.1 Problem

Item FP9 identified an issue with the forward visibility of signals possibly being obstructed by the proposed bend in the road on the Slough Road approach to the roundabout. A separate issue has been identified of potential ‘see through’ along the original alignment.

The kerb-line on the south side has been moved north substantially and no measures are shown to block westbound drivers’ view through the former alignment. This is likely to lead to a late realisation of the traffic signals which are offset to the right.

2.22.2 Recommendation

The area of widened verge must incorporate measures to block visibility along the former alignment of the road. This might include earth works, marker posts, fencing or otherwise. The design must address the sight line requirements for all heights of drivers’ sight lines from 1.05 to 2.0m above road level.

2.23 FP23 – Slough Road Resident Parking

2.23.1 Problem

Vehicles were seen to park on the verges adjacent to properties 2 to 8 on Slough Road on the westbound side of the road, east of an existing bus stop (see Figure 6, below). In addition, there is a commercial access to ‘M&M Autos’.

A proposed bus lay-by is shown on the drawing but no proposals are shown for off- road parking or vehicular accesses. There does not appear to be an alternative location for vehicles to park. It is therefore possible that vehicles may then be parked partly on the road obstructing forward visibility on approach to the roundabout and to vehicles leaving ‘M&M Autos’, as well as conflicting with bus manoeuvres.

2.23.2 Recommendation

Make provision for parking.

Figure 6 – Resident and business parking in verge adjacent to Slough Road approach

2.24 FP24 – Traffic Signal Stacking Lengths

2.24.1 Problem

A number of stop lines on the proposed roundabout have short stacking lengths – notably the circulatory northbound approach adjacent to Uxbridge Road and the eastbound approach adjacent to Pinewood Road. Short stacking lengths can lead to obstruction of exits and late lane changing, which can cause collisions particularly involving two-wheeled vehicles.

The complex elongated form of the junction may increase the likelihood of driver confusion and late lane changing due to disorientation.

2.24.2 Recommendation

Include duplicate lane arrows and destination lettering to assist drivers in promptly selecting the correct lane.

2.25 FP25 – Church Road approach

2.25.1 Problem

Problem FP8 refers to the fact that advance traffic signals for southbound traffic on Church Road have restricted visibility on approach. An additional hazard to this is that the proposed forward view for southbound drivers will be along the existing southbound lane which will become the northbound exit from the modified junction. As a result a southbound driver failing to realise the realignment of the route may continue on the old alignment and collide with a northbound vehicle or with a pedestrian using the crossing. Pedestrians will be crossing a one-way link and will not expect vehicles to travel in this direction.

2.25.2 Recommendation

The island between northbound and southbound traffic on Church Road should be modified to obstruct the existing southbound view along Church Road.

2.26 FP26 – Accesses on Church Road

2.26.1 Problem

There are two existing vehicle accesses south of the British Legion Club on Church Road, providing access to the field and yard behind. Both may be used by large vehicles and the realignment of the road will make left turns more difficult. Left turning vehicles may intrude into the opposing northbound lane of Church Road

2.26.2 Recommendation

See items FP7 and FP25. Accesses here to be considered in amended design.

2.27 FP27 – Pedestrian Crossing on Northbound Exit of Church Road

2.27.1 Problem

On the northbound exit of the junction on Church Road there are 2 lanes at the stop line of the pedestrian crossing whereas downstream of the crossing there is a rapid reduction to 1 lane. This co-location of the two features increases the likelihood of conflicts between merging traffic downstream of the crossing point and may result in lane changing as drivers travel through the pedestrian crossing. This could lead to drivers failing to stop.

Pedestrian flows are likely to be low at most times, so the crossing is likely to be used infrequently. This also could lead to drivers failing to anticipate the signal changing to red. A driver in lane 2 downstream of the crossing who is struggling to merge with heavy traffic in lane 1 could continue across the hatching and into the approaching southbound lane resulting in collisions with southbound traffic.

2.27.2 Recommendation

As the pedestrian crossing is unlikely to be used frequently it may not be necessary to include 2 lanes at the stop line of the pedestrian crossing. If traffic was merged into a single lane it would improve the safety of the crossing and downstream area.

2.28 FP28 – Kerb Alignment Protrudes into Circulatory Carriageway

2.28.1 Problem

Adjacent to Wood Lane traffic in lane 3 on the roundabout is guided by hatching before it passes the exit of the bus link. No road markings are shown across the exit of the bus link which means that drivers in lane 3 may clip the dropped kerb at the edge of the maintenance lay-by. This will be more likely to occur as the hatch markings fade.

2.28.2 Recommendation

Provide edge of carriageway markings on off-side of lane 3 to highlight the alignment.

2.29 FP29 – No Provision Made for Vehicular Access to Substation

2.29.1 Problem

No provision is shown for the electricity substation on the south side of Church Road, to the west of the proposed maintenance lay-by. This is likely to need infrequent vehicle access but possibly involving large vehicles.

2.29.2 Recommendation

In conjunction with the lay-by for signal maintenance, make provision for access to the electricity substation.

2.30 FP30 – Narrowed Central Reservation May Not Be Sufficient to Accommodate the Working Width of Road Restraint System

2.30.1 Problem

The central reservation on Uxbridge Road is shown as being narrowed and realigned under the proposals. This may be insufficient to accommodate an appropriate Road Restraint System.

In addition, at the eastern end of this central reservation the island widens to provide deflection and accommodate a pedestrian route. The alignment and terminals of the Road Restraint System in this area must provide vehicle containment without obstructing pedestrians.

2.30.2 Recommendation

Ensure that a Road Restraint System can be provided with a working width within the kerbed island to prevent intrusion into an opposing traffic lane in the event of a collision. Ensure the Road Restraint System does not obstruct or obscure pedestrians

An energy absorbing terminal will be required for westbound traffic.

2.31 FP31 – Possibility of ‘See-through’ Between Bus Gate and Stop Line at Circulatory

2.31.1 Problem

The stop line where the Uxbridge Road entry meets the circulatory carriageway is less than 50m downstream of the bus gate. It is possible that drivers approaching the bus gate in all-purpose lanes looking ahead to green signals may fail to notice the bus gate signals changing to red. This can lead to vehicles overshooting the stop line and colliding with a bus passing through the gate.

2.31.2 Recommendation

In the detailed design, ensure that the signal heads are designed to minimise the risk of ‘see-through’.

2.32 FP32 – Existing Pedestrian Access Route Severed by Proposed Scheme

2.32.1 Problem

The existing pedestrian access route across the central reservation – adjacent to properties number 1 and 1a on Uxbridge Road – includes a stagger in the Road Restraint System (see Figure 7, below). Crossing in this location is difficult and will become more so with the new arrangement.

2.32.2 Recommendation

A Non-Motorised User assessment – as recommended in item FP11 – should include pedestrian manoeuvres between the north and south sides of Uxbridge Road.

Figure 7 – Existing stagger in Road Restraint and pedestrian access route across A412 Uxbridge Road

3 Seven Hills Road Junction

Original Issues Raised by Arup

The proposals were subject to a Stage 1 Road Safety Audit carried out in February 2009 by Arup. The following items were raised in that report. The designer’s response and the Jacobs audit team comments are also shown.

3.1 SHR1 – No Allowance for Access

3.1.1 Problem

There is an access to a large private estate known as Taidswood Mangat’s on the north side of the junction. No allowance has been made for this access, and there is no alternative available. The access will be close to the junction, and there is a risk that, if retained in its current position, that a vehicle requiring to gain access but not able to enter because of eastbound traffic on Seven Hills Road would be struck from the rear by a vehicle leaving the roundabout.

3.1.2 Recommendation

Provide access to Taidswood, preferably further from the proposed roundabout.

3.1.3 Designer’s Response

Design Team disagrees with recommendation. The Design Team considers that it is unlikely to be possible to provide an alternative access to Taidswood Mangat’s and notes that the proposed situation is little different from the existing arrangement, where a vehicle waiting to turn right would be close to the existing give way line. However, appropriate signage and road markings will be developed in discussion with the highway authority during the detailed design stage.

3.1.4 Supplementary Stage 1 RSA Comments

The audit team agrees with the recommendation made. Although the access will be a similar distance from the junction under the proposals, traffic flows on Seven Hills Road are predicted to be significantly higher with the new development.

3.2 SHR2 – Poor Visibility of Roundabout from the North

3.2.1 Problem

The proposed roundabout is heavily offset to the east of the existing A412 Denham Road. Forward visibility into the roundabout is around a left-hand bend and over a crest. The visibility lines shown on SRA-7901 will require the cutting back of thick woodland and lowering of the intervening ground to achieve an acceptable level of visibility into the junction, and even then the visibility will be over a crest resulting in a layout which could be difficult to comprehend. The A412 is a busy highway, and there is concern that this layout will result in over-runs and rear-end shunt collisions.

3.2.2 Recommendation

Relocate the junction further to the east [Auditor subsequently confirmed that this should read WEST].

3.2.3 Designer’s Response

Design Team disagrees with recommendation. The junction arrangement has been defined by land availability and the Design Team considers that this precludes the recommendation as it would become extremely difficult to achieve appropriate approach geometrics on Seven Hills Road and Denham Road (south).

However, the need to cut back existing vegetation to accommodate the forward visibility on the southbound approach to the roundabout is acknowledged and proposals for this are shown on landscape plans accompanying the planning application.

3.2.4 Supplementary Stage 1 RSA Comments

The audit team agree with the problem raised and recommendation made. There is a specific characteristic of the design that fives particular cause for concern, and that is the absence of any intrusion of the new design into the southbound lane. No part of either the splitter island or the central island fall into the existing southbound lane and as a result drivers are likely to look along the old alignment and therefore to drive along it. We have investigated several examples of this form where as a result drivers travel the wrong way around a roundabout resulting in head-on collisions. While the site is heavily constrained, it is the responsibility of the developer to find a solution acceptable to the Highway Authority so that the safety of road users can be ensured. We set out in a separate Technical Note to assist the highway authority, some suggestions on how this design might be improved.

3.3 SHR3 – Insufficient Northbound Deflection

3.3.1 Problem

A check on the northbound deflection indicates that there is insufficient northbound deflection to reduce approach speeds to less than 30mph. This could lead to over- shoots and collisions at the northbound entry onto the roundabout between circulating and northbound vehicles. It should be noted that the deflection has been measured using a line 1m off the nearside kerb at the roundabout entry rather than the painted edge of carriageway, as this is considered the line more likely to be taken by a driver attempting the straighten path through the junction.

3.3.2 Recommendation

Revise the roundabout design to provide adequate deflection.

3.3.3 Designer’s Response

Design Team agrees with recommendation. However, the design team considers that land availability may limit the ability to increase northbound deflection to accord with the DMRB. Consequently, the Design Team proposes that the use of appropriate signage and road markings, together with the possibility of an overrun area around the central island and/or review of local speed limits, will be developed in discussion with the highway authority during the detailed design stage.

3.3.4 Supplementary Stage 1 RSA Comments

The audit team agrees with the recommendation but disagree with the Design Team’s response. It is the responsibility of the developer to find a solution acceptable to the Highway Authority to ensure the safety of all road users. If an over-run area is provided, particular consideration of motorcycle safety will be important.

3.4 SHR4 – Too Sharp an Entry Angle from the South

3.4.1 Problem

The northbound leg on the A412 turns to the right, before turning sharply left, as a consequence of which the entry angle is too sharp. This can lead to sudden braking, overshoots and loss of control.

3.4.2 Recommendation

Reduce the entry angle.

3.4.3 Designer’s Response

This will be reviewed in conjunction with response to SHR3 above.

3.4.4 Supplementary Stage 1 RSA Comments

The audit team agrees with the recommendation but disagree with the Design Team’s response. It is the responsibility of the developer to find a solution acceptable to the Highway Authority to ensure the safety of all road users.

3.5 SHR5 – Insufficient Circulatory Width

3.5.1 Problem

The approaches to the roundabout along the A412 provide for two lane approaches. The proposed circulatory width appears to require larger vehicles to straddle both lanes. This will result in side-to-side collisions within the roundabout gyratory, or sudden braking leading to rear-end-shunt collisions.

3.5.2 Recommendation

Provide adequate gyratory width to allow for two vehicles side-by-side, or reduce entry to one lane from each direction.

3.5.3 Designer’s Response

The will be reviewed in conjunction with response to SHR3 above.

3.5.4 Supplementary Stage 1 RSA Comments

The audit team doubt whether the circulatory carriageway would operate with a two- lane flow and feel it would be more appropriate to design the roundabout with one lane on each entry, as opposed to increasing the gyratory width. This would assist in resolving the issues stated in SHR2, SHR3 and SHR4.

3.6 SHR6 – Poor Visibility to Right from Round Coppice

3.6.1 Problem

Immediately to the south of the proposed roundabout, a private road leads off to the east to a development known as Round Coppice. Visibility to the right into the roundabout will be obstructed by a new fence along the proposed back of footway, and the extensive tree planting at its rear. This could lead to collisions between southbound vehicles off the roundabout and other emerging from Round Coppice.

3.6.2 Recommendation

Improve visibility to the right.

3.6.3 Designer’s Response

Design Team agrees with recommendation. Back of footway treatment and landscaping will be developed, in discussion with the highway authority, during the detailed design stage.

3.6.4 Supplementary Stage 1 RSA Comments

The audit team agrees with the issue raised but believes it would be most appropriate to relocate access to Round Coppice Road so that it forms a 4th arm of the proposed roundabout. This reduces the likelihood of emerging drivers misjudging speed of vehicles leaving the roundabout, who will not be expecting turning vehicles.

Figure 1 – Existing view to the right on exit of Round Coppice Road

Additional Issues Raised by Jacobs

The following items have been raised as a result of supplementary Stage 1 Road Safety Audit carried out by Jacobs.

3.7 SHR7 – Confusing Signals for Vehicles Emerging from Round Coppice

3.7.1 Problem

Due to the proximity of the Round Coppice access to the proposed roundabout there is a danger that vehicles exiting Round Coppice will believe that vehicles signalling left off the roundabout (heading southbound) are intending to turn into Round Coppice. This could cause vehicles waiting to emerge from Round Coppice to exit prematurely, leading to side-impact collisions. This situation is made more likely by the fact that the southbound exit off the roundabout is at a shallow angle and so indicator signals are unlikely to automatically cancel leaving the roundabout.

3.7.2 Recommendation

As recommended in the supplementary response to FP6, relocate the access to Round Coppice to link in with the proposed roundabout.

3.8 SHR8 – Confusing Signals for Vehicles Exiting the Roundabout Southbound

3.8.1 Problem

Due to the proximity of Round Coppice to the proposed roundabout there is a danger that southbound vehicles following another vehicle turning left into Round Coppice may not understand what the driver is intending to do, causing rear-end shunts. This situation is made more likely by the fact that the southbound exit off the roundabout is at a shallow angle and so indicator signals are unlikely to automatically cancel leaving the roundabout. This confusion could be exacerbated by the fact that, on installation of the roundabout, the Round Coppice access will be more difficult to see, for southbound vehicles, as it will be situated off a sweeping nearside bend.

3.8.2 Recommendation

As recommended in the supplementary responses to FP6 and FP7, relocate the access to Round Coppice to link in with the proposed roundabout.

4 Audit Team Statement

I certify that this report complies with HD19/03 except where stated in the text.

AUDIT TEAM LEADER

Kate Carpenter BEng CEng MICE FCIHT

Technical Director Jacobs Tower Bridge Office Date 19/11/2010

AUDIT TEAM MEMBER

Caroline Nash BEng CEng MICE Principal Road Safety Engineer Jacobs Tower Bridge Office

Jacobs Engineering U.K. Limited Registered Office: 1180 Eskdale Road, Winnersh, Wokingham, RG41 5TU, UK Registered in England and Wales No. 2594504

5 Supplementary Road Safety Audit Exception Response

Supplementary Stage 1 Road Safety Audit: Exception Response

Scheme Name: Pinewood Studios – Five Points Roundabout Date:

The issues categorised in the road safety audit as ‘Problem’ matters are those causing serious concern and are summarised below. The purpose of this form is for the scheme Overseeing Organisation to respond to the ‘Problem’ matters in accordance with the procedure set out in HD 19/03. Responses should be sent to the named Audit Team Leader at Jacobs, Tower Bridge Court, 226 Tower Bridge Road, London SE1 2UP Item Summary of Problem Response from Overseeing Organisation ¹ FP1 Loss of parking FP2 Existing Sign Next to Footway Too Low FP3 Visibility at Pub Access FP4 Visibility Lines Crossing Land Outside Highway Boundaries FP5 Incorrect Use of Right Turn Arrow FP6 Poor Forward Visibility of Signals FP7 Existing Bus Stop on Corner FP8 Forward Visibility of Signals FP9 Forward Visibility of Signals FP10 See Through of Pedestrian Signals FP11 Pedestrians Crossing to the Central Island FP12 Access Off Wood Lane Appears Closed FP13 Visibility Lines Crossing land Outside Highway Boundaries FP14 Service Lay-bys Obstructing Visibility of Signals FP15 Location of Crossing of Bus Lane FP16 Incorrect Use of Tactile Paving FP17 Location of Secondary Signal Heads FP18 Corner Visibility Passing Outside Highway Limited and Over Maintenance Lab-bys FP19 Clashes Between Swept Paths of Vehicles FP20 Traffic Island in Wood Lane

FP21 Possible Obstruction of Pedestrian Route FP22 ‘See-through’ on Slough Road Approach FP23 Slough Road Residential Parking FP24 Traffic Signal Stacking Lengths FP25 Church Road Approach FP26 Accesses on Church Road FP27 Pedestrian Crossing on Northbound Exit of Church Road FP28 Kerb Alignment Protrudes into Circulatory Carriageway FP29 Provision Made for Vehicular Access to Substation FP30 Narrowed Central Reservation May Not Be Sufficient to Accommodate the Working Width of Road Restraint System FP31 Possibility of ‘See-through’ Between Bus Gate and Stop Line at Circulatory FP32 Existing Pedestrian Access Route Severed by Proposed Scheme

Supplementary Stage 1 Road Safety Audit: Exception Response

Scheme Name: Pinewood Studios – Seven Hills Road junction Date:

The issues categorised in the road safety audit as ‘Problem’ matters are those causing serious concern and are summarised below. The purpose of this form is for the scheme Overseeing Organisation to respond to the ‘Problem’ matters in accordance with the procedure set out in HD 19/03. Responses should be sent to the named Audit Team Leader at Jacobs, Tower Bridge Court, 226 Tower Bridge Road, London SE1 2UP Item Summary of Problem Response from Overseeing Organisation ¹ SHR1 No Allowance for Access SHR2 Poor Visibility of Roundabout from the North SHR3 Insufficient Northbound Deflection SHR4 Too Sharp an Entry Angle from the South SHR5 Insufficient Circulatory Width SHR6 Poor Visibility to Right from Round Coppice SHR7 Confusing Signals for Vehicles Emerging From Round Coppice SHR8 Confusing Signals for Vehicles Exiting the Roundabout Southbound

¹ For projects not initiated by the Highways Agency, the response should be arranged by the Design Project Manager or the Local Highway Authority as appropriate.

Respondent

Name:

Signed:

On behalf of: (Name of Design / Overseeing Organisation)

Date

6 Other Issues

6.1 Non-Motorised Users

A Non Motorised User Audit does not appear to have been carried out at either site. Buckinghamshire County Council has adopted the Design Manual for Roads and Bridges for all highways under their control and an NMU Audit should be carried out in accordance with section 42/05.

6.2 Predicted Traffic Flows

In the Transportation Statement written by the Highway Authority, concerns over unrealistic traffic generation levels were raised. Due to the rural location of the site and its proximity to the M1, access to the Pinewood site by public transport was predicted to be less than the original Arup estimations. It is critically important that the predicted traffic flows take into account likely actual traffic flows and all known factors and are agreed upon by all parties.

6.3 Street Lighting

The A412 in this area – from the bridge over the M25 to the M40 Denham Roundabout junction – was part of the Buckinghamshire County Council Street Light Switch Off scheme. This involved mitigation measures along with switching off the street lighting for a continuous 3-year period and was implemented on 28/08/07. The lighting requirements of the junction will need to be considered – not just on the junction but on the roads leading into it.

7 Summary

7.1 General

The audit team feels that the design of both junctions in the drawings provided could be improved.

Many of the issues raised by Arup in the Stage 1 audit were dismissed by the Design Team on the basis of land constraints. We recognise the constraints at each of the sites, particularly with regards to land but it is still necessary to ensure safe design.

7.2 Five Points Roundabout

The design of this junction is complicated, particularly in comparison to the existing layout. This is likely to lead to driver and other road user confusion, which in turn will lead to road safety implications. The proposed traffic signal design is likely to cause journey times to be significantly longer through the junction than they currently are.

The number of Road Safety Audit issues raised - at the Stage 1 carried out by Arup and the Supplementary Stage 1 carried out by Jacobs – is also a cause for concern.

We believe that significant alterations and improvements should be made, with the issues raised in this audit taken into consideration.

7.3 Seven Hills Road Junction

It is the opinion of the audit team that the proposed design at this junction is also unsatisfactory in its current form. Off-line roundabouts commonly lead to poor visibility unless totally removed from the existing route and can cause confusion amongst drivers, particularly at night and in adverse weather conditions.

The reason for the roundabout being offset to the east appears to be land ownership constraints. As stated previously, a solution must be found within these constraints which does not lead to unacceptable levels of road user casualties.

Appendix A Documents Used

Drawings:

FP-7000 (Arup, revision 02)
SRA-7000 (Arup, revision 02)

Documents:

A412 Denham Road/Seven Hills Road Roundabout Stage 1 Road Safety Audit (Arup, document reference: 09/7492)
Five Points Roundabout Stage 1 Road Safety Audit (Arup, doc reference:09/7491)
Pinewood Stage 1 Road Safety Audit – Designer’s Response (Arup, document reference n/a)
Transportation Statement to the Planning Inspectorate at Buckinghamshire County Council in respect of the future appeals regarding Planning Applications 09/00706, 07&08 for proposed development at Pinewood Studios (Buckinghamshire County Council, document reference n/a)

Appendix B Items Considered

The table below summarises the categories of hazard evaluated in this Supplementary Stage 1 Road Safety Audit, which are described in detail above. The reference numbers in the table below are based on the annex checklists in HD19/03.

Categories of Hazards Evaluated in this Supplementary Stage 1 Road Safety Audit A1 General Departures from standards Cross-sections & cross-sectional variation Drainage Landscaping Statutory undertakers' apparatus Lay-bys Access Emergency vehicles Future widening Adjacent development Basic Design Principles A2 Local Alignment Visibility New/existing road interface Vertical alignment A3 Junctions Layout Visibility A4 Non Motorised User Provision Adjacent land Pedestrians/cyclists Equestrians A5 Signs, Road Markings & Lighting Signs Lighting Poles/Columns Road Markings

Appendix C Problem Location Plans

FP20 FP3 FP30

FP28 FP13 FP31

FP32

FP4 FP4

FP12

FP24

FP21

FP16

FP5 FP5

FP1 FP1 FP16

FP14

FP11

FP15

FP6 FP6

FP10

FP29

FP17

FP9 FP9

FP22

FP19

FP23

FP27

FP16

FP18

FP25

FP8 FP8 FP26

FP7 FP7

SHR4

SHR1

SHR3

SHR7 & SHR7

SHR6, SHR6, SHR8 SHR8 SHR2

Appendix C Designer’s Response to Five Points Audit only

Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

207042 Issue 2 | January 2011

This report takes into account the particular instructions and requirements of our client. Ove Arup & Partners Ltd It is not intended for and should not be relied 13 Fitzroy Street upon by any third party and no responsibility is London undertaken to any third party. W1T 4BQ United Kingdom arup.com Job number 207042

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

Contents

Page

1 Introduction 1 1.1 Background 1 1.2 Road Safety Audit History 1 1.3 Five Points Junction 1 1.4 Supplementary Designer’s Response 2 1.5 Additional Issues Raised by Jacobs 16

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

1 Introduction

1.1 Background An outline planning application has been made to South Bucks District Council for new development associated with Pinewood Studios in Iver Heath, Buckinghamshire. In parallel, detailed planning applications have been made for off-site highway works at two locations which form part of the overall project and are required to accommodate forecast traffic flows associated with the new development, previously committed development and background traffic growth over time. The detailed applications cover works at the: • Five Points junction (A412 Uxbridge Road / Pinewood Road / A412 Church Road / A4007 Slough Road / Wood Lane) and; • Seven Hills Road / A412 Denham Road junction.

1.2 Road Safety Audit History Stage 1 Road Safety Audits were undertaken on the Five Points and Seven Hills Road junction proposals in February 2009 by an independent team based in Arup’s Cardiff office (Richard Thomas and Chris van Lottum). The Design Team subsequently prepared Designer’s Responses to these audits in July 2009 and submitted them to the highway authority, Buckinghamshire County Council (BCC). At the request of BCC, supplementary Stage 1 Road Safety Audits were carried out in November 2010 by Jacobs (Kate Carpenter and Caroline Nash).

1.3 Five Points Junction This report represents the Designer’s Response to the issues raised in the Supplementary Stage 1 Road Safety Audit report. It should be noted that this report only considers the audit comments/recommendations for the Five Points Junction and not the Seven Hills Rd/Denham Rd roundabout proposals. A signalised T-junction is now proposed for the Seven Hills Rd/Denham Rd junction due to BCC concerns. For completeness and future reference, the original Stage 1 Road Safety Audit Problem, Recommendation and Designer’s Response are included, together with the Supplementary Stage 1 RSA Comments by Jacobs. In addition, where a new Problem and Recommendation were made by Jacobs, these too have been included. The issues and recommendations are presented in the order in which they appear in the Stage 1 Road Safety Audit report. The Preliminary scheme design drawings have been updated to incorporate, where applicable, the recommendations made by both the Arup Cardiff and Jacobs audit teams.

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

1.4 Supplementary Designer’s Response

1.4.1 FP1 – Loss of Parking Problem A bus lane is provided along the eastbound lane of the A412. No indication is given as to where this starts. There is residential access required along the side of the bus lane, and resident parking occurs on the existing footway and verge in this area. This could result in local access being obtained by driving along the bus lane, which could indicate to other drivers that the bus lane is not full-time, leading to its use to jump queues. There is also a risk that local inhabitants could park within the bus lane causing buses to pull back out into traffic leading to collisions. Recommendation Ensure the bus lane is adequately signed to make its function clear to drivers. Designer’s Response Design Team agrees with recommendation. Appropriate signage for the bus lane will be developed, in discussion with the highway authority, during the detailed design stage. Supplementary Stage 1 RSA Comments We agree with the issue raised and the recommendation and also recommend that the Police are requested to provide relevant enforcement. Supplementary Designer’s Response Appropriate signage for the bus lane will be developed, in discussion with the highway authority and the Police, during the detailed design stage.

1.4.2 FP2 – Existing Sign Next to Footway Too Low Problem There is an existing direction sign on the A412 to the east of the existing roundabout which is located close to the eastbound [northern] footway. The sign face is less than 1.6m high [it is assumed that this refers to the mounting height] and could be collided with by a pedestrian walking near the back of the footway. Recommendation Raise the level of the sign to where it is no longer a risk to pedestrians. Designer’s Response Design Team agrees with recommendation. The positioning of the sign will be assessed as part of the overall signage strategy, in discussion with the highway authority, during the detailed design stage. Supplementary Stage 1 RSA Comments

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

The audit team did not have a plan showing the location of this sign and could not identify it while on site. Supplementary Designer’s Response The height/positioning of the sign will be assessed as part of the overall signage strategy, in discussion with the highway authority, during the detailed design stage.

Figure 0 – Sign adjacent to northern footway, A412 Uxbridge Road

1.4.3 FP3 – Visibility at Pub Access Problem The A412 Uxbridge Road leading to the west from the Five Points Roundabout is currently hatched out on the inside to direct drivers to the outer lane (see Figure 1, below). The reason for this is not known but the audit team speculates that this is to serve a visibility problem on for drivers entering and emerging from the access at the Crooked Billet public house and the houses and garage beyond. The westbound lane of Uxbridge Road is narrowed by setting the central reserve to the south to enable the provision of an eastbound bus lane. This will push traffic emerging from the roundabout to the left and will reduce visibility of these vehicles from the public house access, increasing the risk of collisions. Recommendation Increase visibility to the right for vehicles emerging from the public house. Designer’s Response Design Team agrees with recommendation. However, following discussions with the highway authority it is expected that two full westbound lanes on the Uxbridge Road exit will be necessary to accommodate the forecast flows for the design year of 2022. Therefore, the detailed design will need to address this, together with visibility for the accesses to the public house, properties and garage. Supplementary Stage 1 RSA Comments We agree with the issue raised and note that the Design Team suggest two west- bound lanes are needed, whilst the current proposal only shows a single lane.

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

Supplementary Designer’s Response Bus gate has been removed from proposals and central reservation realigned further north, so that southern kerbline can also be realigned further north to increase visibility to the right for vehicles emerging from the public house. In addition a left-turn lane into the public house and two westbound lanes also incorporated – refer to Arup drwg. no. FP-7000-05.

Figure 1 – Crooked Billet public house access on A412 Uxbridge Road

1.4.4 FP4 – Visibility Lines Crossing Land Outside Highway Boundaries Problem The stopping sight distance line for the turn to Pinewood Road off A412 Uxbridge Road is shown for 60kph at 90m. This crosses outside the highway boundary. The distance shown for 60kph may not reflect the actual 85%ile vehicle speeds on the dual carriageway approach to the roundabout. As there is no control of what happens outside the highway boundary, it would appear that the distance shown does not reflect the actual distance available. There is a risk of heavy braking and loss of control. Recommendation Ensure the forward visibility is not obstructed. Designer’s Response Design Team agrees with the recommendation. However, as the applicant has no control over the land beyond the highway boundary in this location, the available SSD is limited. A further review of the SSD shown on Drawing FP-7901 indicates that without encroaching outside the highway boundary the available SSD for the turn in question is approximately 70m. This equates to “one step below the

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

desirable minimum” for 60kph as set out in TD 9/93. The Design Team proposed that the issue of design speeds and relaxations are reviewed with the highway authority. In addition, appropriate signage and road markings will be developed in discussion with the highway authority, during the detailed design stage. Supplementary Stage 1 RSA Comments The audit team were not supplied with drawing FP-7901 or any other documents showing evidence for the selection of the design speed. The audit team agrees with the issue raised. The speed limit on the Uxbridge Road approach to the existing roundabout is 40mph which equates to a design speed of 70kph. The desirable minimum SSD for a 70kph design speed is 120m, with ‘one step below’ coming to 90m. 70m is equivalent to two steps below the desirable minimum. Supplementary Designer’s Response Revised scheme proposals achieve 120m forward visibility (40mph DMSSD) to both primary signals. Inter-visibility in accordance with TD50/04 – refer to Arup drwg. no. FP-7900-05 and 7901-05).

1.4.5 FP5 – Incorrect Use of Right Turn Arrow Problem Right-turn arrow markings are indicated on the north side of the gyratory, opposite Pinewood Road. This could lead to confusion and a driver entering the proposed bus link. Recommendation Provide straight-ahead road markings in this location. Designer’s Response Design Team agrees with recommendation. Straight ahead road markings will be incorporated. Supplementary Stage 1 RSA Comments We agree with the problem and Design Team’s revised proposal. The use of lettering for destinations (referred to in item FP24) will be beneficial given that all 3 lanes will now indicate ‘AHEAD ONLY’. Supplementary Designer’s Response Straight ahead arrows and “indicative” destinations incorporated – refer to Arup drwg. no. FP-7000-05.

1.4.6 FP6 – Poor Forward Visibility of Signals Problem Traffic signals on the southbound approach to the proposed gyratory are located around a bend. Drawing FP-7901 indicates that the off-side signal can just be seen by an approaching driver, but this may be obstructed by other vehicles and the

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

heavily wooded area behind the verge. There is a risk that approaching drivers would not appreciate the layout ahead, leading to rear-end shunts and over- running of the stop line. Recommendation Set back the verge to increase visibility of both signals. Designer’s Response Design Team disagrees with recommendation as the applicant has no control over the land beyond the highway boundary in this location and therefore the verge cannot be set back. However, the Design Team proposes that the issues of design speeds and relaxations are reviewed with the highway authority. In addition, appropriate signage, road markings and landscaping, together with the possibility of using high level signal heads, will be developed in discussion with the highway authority during the detailed design stage. Supplementary Stage 1 RSA Comments This audit team were not supplied with drawing FP-7901. We agree with the problem raised and recognise the constraints. We recommend that the stop line is set back towards the northern corner of the splitter island to improve forward visibility. This would provide good forward visibility of the off- side signal and, provided the near-side verge is managed, good forward visibility of the near-side signal can also be achieved. Supplementary Designer’s Response Stop line has been repositioned further north, so that forward visibility to nearside primary is achievable – refer to Arup drwg. no. FP-7000-05.

1.4.7 FP7 – Existing Bus Stop on Corner Problem There is an existing bus stop on the corner where the westbound traffic on Church Road will be turned to the south-west (see Figure 2, below). There is a risk that drivers may try to overtake the bus and not realise that their route turns to the left, leading to them travelling along the eastbound leg of the road in the wrong direction. Recommendation Relocate the bus stop away from the diverge. Designer’s Response Design Team agrees with the recommendation. The positioning of the bus stop will be assessed, in discussion with the highway authority, during the detailed design stage. Supplementary Stage 1 RSA Comments

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

This bus stop adjacent to the British Legion Club is likely to be used by a significant number of people at certain times. No provision for relocation is shown. Hazards at this location are increased as there are several vehicular accesses in the area which may conflict with potential bus stop locations. It is recommended that all hazards are considered in the design to ensure provision for a safe bus stop location is made. Supplementary Designer’s Response Note added to drawing accordingly – refer to Arup drwg. no. FP-7000-05. The precise positioning of the bus stop will be assessed, in discussion with the bus operator and highway authority, during the detailed design stage.

Figure 2 – Existing bus stop on Church Road

1.4.8 FP8 – Forward Visibility of Signals Problem Traffic signals on the southbound approach to the proposed gyratory are located around a bend. Drawing FP-7902 indicates that the off-side signal can just be seen by an approaching driver, but this may be obstructed by other vehicles and the heavily wooded area behind the verge. There is a risk that approaching drivers would not appreciate the layout ahead, leading to rear end shunts and over- running of the stop line. Recommendation Set back the verge to increase visibility of both signal heads. Designer’s Response Design Team disagrees with the recommendation as the applicant has no control over the land beyond the highway boundary on the south east side of Church Road

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

until approximately the point at which the nearside kerb diverges from its present alignment and therefore the verge cannot be set back. However, a further review of the achievable SSD shown on Drawing FP7902 indicates that an SSD of approximately 75m to the nearside is achievable within the highway boundary or land controlled by the applicant. This is greater than the value of 70m specified as “one step below the desirable minimum” for a 60kph design speed in TD 9/93. The Design Team proposed that the issues of design speeds and relaxations are reviewed with the highway authority. In addition, appropriate signage, road markings and landscaping together with the possibility of using high-level signal heads, will be developed in discussion with the highway authority during the detailed design stage. Supplementary Stage 1 RSA Comments This audit team were not supplied with drawing FP-7901 or other documents showing evidence for the selection of the design speed. The audit team agrees with the issue raised. The speed limit on the Church Road approach to the existing roundabout is 40mph which equates to a design speed of 70kph. The desirable minimum SSD for a 70kph design speed is 120m, with ‘one step below’ coming to 90m. See also item FP25. Supplementary Designer’s Response The Design Team proposes that the existing 30mph speed restriction through Iver Heath, be extended further southwest along Church Rd to encompass the approach to the proposed signalised roundabout. On this basis, the scheme proposals achieve 90m forward visibility (30mph DMSSD) to primary signal in accordance with TD50/04 – refer to Arup drwg. no. FP-7902-05 and 7900-05.

1.4.9 FP9 – Forward Visibility of Signals on Slough Road Problem Traffic signals on the westbound approach to the proposed gyratory are located around a bend. Drawing FP-7902 indicates that the off-side signal can just be seen by an approaching driver, but this may be obstructed by other vehicles and the heavily wooded area behind the verge. There is a risk that approaching drivers would not appreciate the layout ahead, leading to rear end shunts and over- running of the stop line. Recommendation Set back the verge to increase visibility of both signal heads. Designer’s Response Design Team agrees with recommendation as the verge can be set back within the existing highway boundary or land within the applicant’s control. Supplementary Stage 1 RSA Comments

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

The audit team agree with the issue and the recommendation made. See also item FP22 related to the issue of potential ‘see-through’ over the build out. Supplementary Designer’s Response The Design Team confirms that the verge can be set back within existing highway land to achieve the necessary forward visibility. In addition, earthworks have been incorporated into the scheme proposals accordingly to prevent “see- through” – refer to Arup drwg. no. FP-7000-05.

1.4.10 FP10 – ‘See-through’ of Pedestrian Signals Problem A pedestrian crossing route is provided between the central gyratory island, across a triangular splitter island, to the south side of the A4007. There is no indication at this stage as to what method of control of pedestrian movements is proposed, but it is noted that this movement is in an almost straight line across two separate carriageways. Depending which type of pedestrian signal is proposed, there is a risk that a pedestrian crossing on road may confuse opposing signal and continue to cross both carriageways. Recommendation Provide nearside pedestrian heads only. Designer’s Response Design Team agrees with recommendation. The traffic signal equipment/arrangements will be assessed, in discussion with the highway authority, during the detailed design stage. Supplementary Stage 1 RSA Comments If these facilities provide for cyclists in the form of Toucan crossings far side indicators would be used and ‘see-through’ would remain a problem. Supplementary Designer’s Response The traffic signal equipment/arrangements will be assessed, in discussion with the highway authority, during the detailed design stage.

1.4.11 FP11 – Pedestrians Crossing to the Central Island Problem Pedestrian movements are provided for around the gyratory and between the central gyratory island and Pinewood Road. There is also a link across the central island between Pinewood Road in the north and the A4007. There is a risk that pedestrians travelling between Pinewood Road and Wood Lane to the south would cross directly over the central island and make use of the traffic signal phases to cross the southern side of the gyratory and bus lane, where they could be vulnerable should the signals change. Recommendation

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

Provide deterrents to dissuade pedestrians from crossing the central island in this manner. Direction arrows to assist pedestrians in way-finding could also be provided. Designer’s Response Design Team agrees with recommendation. The signage and landscaping will be assessed, in discussion with the highway authority, during the detailed design stage. Supplementary Stage 1 RSA Comments In addition to the issue raised, a Non-Motorised User appraisal including both pedestrian and cyclist activity should be undertaken in accordance with DMRB HD 42/05. This would help to identify existing and likely future NMU desire lines and appropriate provision in the scheme. Supplementary Designer’s Response Design Team agrees that a Non-Motorised User appraisal should be carried out as part of the design process. In advance of this being carried out, an independent review of the pedestrian and cycle facilities has been carried out. One comment made is that the eastern part of the pedestrian route, across the central island, will be underused. It has therefore been removed from the scheme proposals accordingly – refer to Arup drwg. no. FP-7000-05.

1.4.12 FP12 – Access off Wood Lane Appears Closed Problem A solid edge line is shown across the existing access to the Crooked Billet public House off Wood Road. This is interpreted as indicating that this access is to be closed. As a result, the only access would be left-in/left-out on the A412 Uxbridge Road. The A412 Uxbridge Road is a dual carriageway, and such a closure would lead to long diversions as there are no near-by U-turn facilities. There is a chance that drivers could try to cross the widened grass central reserve beyond the western limit of the central island safety fence, leading to collisions. Recommendation Do not close the access to the Crooked Billet of Wood Road. Designer’s Response Design Team agrees with recommendation. This is acknowledged to be an error on Drawing FP-7000 as it is not the intention to close this access to the Crooked Billet public house and will be rectified in the next revision of the drawings. Supplementary Stage 1 RSA Comments At present the access is at a point where there is one lane in each direction on Wood Lane (see Figure 3, below). The proposals will add one extra northbound lane on the approach to the traffic signals and adjacent to this access. This poses an additional hazard of a driver leaving the car park turning right and failing to register a vehicle in the offside lane possibly concealed by a vehicle in the nearside lane, resulting in collisions. It is recommended that the location of this car park access is reviewed in order to address this problem.

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

Supplementary Designer’s Response ”Keep Clear” road markings have been incorporated into the scheme proposals accordingly – refer to Arup drwg. no. FP-7000-05. In addition, it may be prudent to ban the right turn from the public house. This would need to be discussed/agreed with BCC in the future.

Figure 3 – Existing traffic island on Wood Lane with Crooked Billet PH access in background, on the left

1.4.13 FP13 – Visibility Lines Crossing Land Outside Highway Boundaries Problem An available sight distance from Wood Lane into the A412 Uxbridge Road appears to be 56m. This crosses behind the highway boundary. A vehicle passing through an uninterrupted green phase could be travelling at too rapid a speed to stop at the pedestrian signals on the A412 Uxbridge Road and could collide with a pedestrian. Recommendation Link the second phase on the westbound A412 Uxbridge Road to operate only when the phase from Wood Road is on red. Designer’s Response Design Team agrees with recommendation. The traffic signal equipment/arrangements will be assessed, in discussion with the highway authority, during the detailed design stage. Supplementary Stage 1 RSA Comments

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

We agree with the issue raised and recommendations. In addition we note that the proposed single lane width at the pedestrian crossing appears to be almost 7 metres. This may cause drivers to travel in 2 lanes of traffic resulting in ‘side- swipe’ collisions and may increase the likelihood of drivers failing to see pedestrians at signals. We would therefore recommend a maximum lane width of 4 metres between the exit of the roundabout to the start of the 2-lane section beyond the petrol filling station. See item FP32. Supplementary Designer’s Response The traffic signal equipment/arrangements will be assessed, in discussion with the highway authority, during the detailed design stage. Furthermore, inter-visibility is in accordance with TD50/04. Two westbound lanes have also been incorporated into scheme proposals – refer to Arup drwg. no. FP-7000-05.

1.4.14 FP14 – Service Lay-bys Obstructing Visibility of Signals Problem Two service lay-bys are proposed on the gyratory. They are both located in areas where traffic will be turning, and vehicles parked in the lay-bys will obstruct visibility of signal heads. This could lead to over-running, heavy braking and rear- end shunts, and loss of control. Recommendation Relocate the service lay-bys to where visibility of signal heads is not obstructed. Designer’s Response Design Team agrees with recommendation. The positioning of these lay-bys will be assessed, in discussion with the highway authority, during the detailed design stage. Supplementary Stage 1 RSA Comments In addition to legitimate use by maintenance vehicles, these lay-bys may be used by drivers unsure of their destination as a result of the complex layout of the junction. In both locations a stationary vehicle will not be aligned parallel to the approaching streams of traffic and the merging manoeuvre necessary on leaving the lay-bys will require drivers to look back to their near-side where visibility is often compromised. Supplementary Designer’s Response Visibility envelopes and lay-bys have been coordinated – refer to Arup drwg. no. FP-7000-05. Lay-by surface materials and kerb upstand heights will also be considered, during detailed design stage, to reduced conspicuousness of lay-bys to other drivers.

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

1.4.15 FP15 – Location of Crossing of Bus Lane Problem A dedicated bus lane is proposed in the central island of the gyratory. A pedestrian route crosses this, for which no tactile paving is proposed. Visually impaired pedestrians may not realise they are crossing a length of carriageway and step into the path of a bus. In addition, although it is assumed that the bus would have priority, if a driver needed to stop, it appears the rear of the bus would protrude into the gyratory carriageway where it could be struck by a passing vehicle. Recommendation Provide tactile paving at the crossing and locate it further to the south in order that a bus could stop without intruding into the gyratory carriageway. Designer’s Response Design Team agrees with recommendation. The position/layout of the tactile paving will be assessed, in discussion with the highway authority, during the detailed design stage. Supplementary Stage 1 RSA Comments The audit team agrees with the issue raised and the recommendation. The drawing for this audit does show tactile paving but in an inconsistent way. As stated in the supplementary comments for FP11, the audit team recommends that a Non- Motorised User audit is carried out to assist with the positioning of proposed crossing points and footpath links. Supplementary Designer’s Response Design Team agrees that a Non-Motorised User appraisal should be carried out as part of the design process. Tactile paving has been incorporated into scheme proposals accordingly – refer to Arup drwg. no. FP-7000-05.

1.4.16 FP16 – Incorrect Use of Tactile Paving Problem Tactile paving has been installed on the traffic islands in accordance with the layout in paragraph 1.5.3.3 of the Guidance on the use of Tactile Paving Surfaces published by the DETR. This refers to triangular islands. The traffic islands are not the small islands shown in the guidance, and pedestrians must walk some considerable distances in place between crossings. They may interpret the crossings as uncontrolled rather than controlled. Recommendation Provide L-shaped tactile paving at the crossings. Designer’s Response Design Team agrees with recommendation. The position/layout of the tactile paving will be assessed, in discussion with the highway authority, during the detailed design stage.

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

Supplementary Stage 1 RSA Comments Consult with local access groups and/or representative bodies for visually impaired users to establish what form of provision, if any, is required at each location. Supplementary Designer’s Response Local access groups and/or representative bodies for visually impaired users to be consulted during detailed design stage.

1.4.17 FP17 – Location of Secondary Signal Heads Problem Many of the secondary crossing heads are located in close proximity to the pedestrian crossings. Where there are multiple lanes, the secondary head may be difficult for some drivers to observe. This could lead to delay in moving off, resulting in rear-end shunt collisions. Recommendation Provide additional clearance between the signal heads and the give way lines where possible. Designer’s Response Design Team agrees with recommendation. The traffic signal equipment/arrangements will be assessed, in discussion with the highway authority, during the detailed design stage. Supplementary Stage 1 RSA Comments It may be appropriate in some locations to install gantry mounted signals if a secondary signal head is difficult to position where it can be seen by drivers in all lanes. Supplementary Designer’s Response Secondary signals relocated accordingly – refer to Arup drwg. no. FP-7000-05.

1.4.18 FP18 – Corner Visibility Passing Outside Highway Limited and Over Maintenance Lay-bys Problem Corner visibility is indicated covering areas which are to be kept clear of planting and obstacles. Several sight lines as shown cross either into woodland behind the existing highway limit or across maintenance lay-bys. This could cause forward stopping sight distance to be compromised, leading to rear-end shunt collisions. Recommendation Ensure visibility lines are kept clear at all times. Designer’s Response

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

Design Team agrees with recommendation. The visibility splays within the highway boundary or land in the applicant’s control will be designed such that they are kept clear of the obstruction, in discussion with the highway authority, during the detailed design stage. Supplementary Stage 1 RSA Comments This team supports the comments raised and recognises that there are constraints on available land. We would recommend a structured program of landscape management to keep vegetation trimmed and, at some locations, alteration of the layout may be required to provide acceptable visibility of signals. See item FP4. Supplementary Designer’s Response Visibility envelopes and landscape proposals to be closely coordinated during detailed design stage.

1.4.19 FP19 – Clashes Between Swept Paths of Vehicles Problem There are a number of places where the swept path diagrams indicate clashes between large vehicles. There are other places where the plots indicate a possibility that vehicles over-run into adjacent lanes. This can lead to collisions between vehicles, and sudden breaking with rear-end shunt collisions as a result. Recommendation Check the swept path plots and provide appropriate widening. Designer’s Response Design Team agrees with recommendation. The Design Team confirms that the vehicle swept paths will be reviewed, in discussion with the highway authority, to ensure that widths are appropriate for the expected movements of larger vehicles. Supplementary Stage 1 RSA Comments The swept path drawings were not made available to this audit team. The circulatory carriageway between the exit and entry of Church Road has a tight radius which may result in turning vehicles overhanging an adjacent vehicle. Although hatched areas are provided to assist large vehicles to turn, this passes through the pedestrian crossing. This may lead pedestrians to stand in the hatched areas, believing it is safe to do so during the red pedestrian phase. It is recommended that the arrangement is adjusted – if possible - to exclude the hatching proposed. Supplementary Designer’s Response Lane widths/configurations adjusted to accommodate large vehicles. In addition, pedestrian crossing has been removed and hatching adjusted accordingly – refer to Arup drwg. no. FP-7000-05.

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

1.5 Additional Issues Raised by Jacobs The following items have been raised as a result of supplementary Stage 1 Road Safety Audit carried out by Jacobs.

1.5.1 FP20 – Traffic Island in Wood Lane Problem An existing traffic island (see Figure 3, in item 2.12 and Figure 4, below) on Wood Lane south of the access to the Crooked Billet public house is not shown as being removed on drawing no. FP-7000. In order to provide 2 northbound lanes here this island would need to be removed. Recommendation The island should be included on design drawings and any safety impacts considered. Supplementary Designer’s Response Island shown on design drawings and annotated accordingly - refer to Arup drwg. no. FP-7000-05. Tie-in to existing road markings in to be established during detailed design stage.

Figure 4 – Existing traffic island on Wood lane with evidence of vehicles overrunning nearside kerb

1.5.2 FP21 – Possible Obstruction of Pedestrian Route Problem There are a number of items (cabinets and a mast) of statutory undertakers’ apparatus adjacent to the exit of the roundabout onto Wood Lane. It is possible

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

that some of the apparatus may obstruct the proposed pedestrian route in this location. Recommendation Establish the location of all items with respect to the proposed footway to ensure that the pedestrian route is unobstructed. Supplementary Designer’s Response Cabinet shown on design drawings and annotated accordingly - refer to Arup drwg. no. FP-7000-05.

Figure 5 – Existing statutory undertakers’ cabinets and mast in verge adjacent to Wood Lane exit

1.5.3 FP22 – ‘See-through’ on Slough Road Approach Problem Item FP9 identified an issue with the forward visibility of signals possibly being obstructed by the proposed bend in the road on the Slough Road approach to the roundabout. A separate issue has been identified of potential ‘see through’ along the original alignment. The kerb-line on the south side has been moved north substantially and no measures are shown to block westbound drivers’ view through the former alignment. This is likely to lead to a late realisation of the traffic signals which are offset to the right. Recommendation

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

The area of widened verge must incorporate measures to block visibility along the former alignment of the road. This might include earth works, marker posts, fencing or otherwise. The design must address the sight line requirements for all heights of drivers’ sight lines from 1.05 to 2.0m above road level. Supplementary Designer’s Response Earthworks have been incorporated into the scheme proposals accordingly to prevent “see-through” – refer to Arup drwg. no. FP-7000-05.

1.5.4 FP23 – Slough Road Resident Parking Problem Vehicles were seen to park on the verges adjacent to properties 2 to 8 on Slough Road on the westbound side of the road, east of an existing bus stop (see Figure 6, below). In addition, there is a commercial access to ‘M&M Autos’. A proposed bus lay-by is shown on the drawing but no proposals are shown for off-road parking or vehicular accesses. There does not appear to be an alternative location for vehicles to park. It is therefore possible that vehicles may then be parked partly on the road obstructing forward visibility on approach to the roundabout and to vehicles leaving ‘M&M Autos’, as well as conflicting with bus manoeuvres. Recommendation Make provision for parking. Supplementary Designer’s Response Lay-by is intended to be for private parking. Drawing annotated accordingly – refer to Arup drwg. no. FP-7000-05.

Figure 6 – Resident / business parking in verge adjacent to Slough Road approach

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

1.5.5 FP24 – Traffic Signal Stacking Lengths Problem A number of stop lines on the proposed roundabout have short stacking lengths – notably the circulatory northbound approach adjacent to Uxbridge Road and the eastbound approach adjacent to Pinewood Road. Short stacking lengths can lead to obstruction of exits and late lane changing, which can cause collisions particularly involving two-wheeled vehicles. The complex elongated form of the junction may increase the likelihood of driver confusion and late lane changing due to disorientation. Recommendation Include duplicate lane arrows and destination lettering to assist drivers in promptly selecting the correct lane. Supplementary Designer’s Response “Indicative” destinations incorporated – refer to Arup drwg. no. FP-7000-05. The actual destinations will be agreed with the highway authority during the detailed design stage.

1.5.6 FP25 – Church Road approach Problem Problem FP8 refers to the fact that advance traffic signals for southbound traffic on Church Road have restricted visibility on approach. An additional hazard to this is that the proposed forward view for southbound drivers will be along the existing southbound lane which will become the northbound exit from the modified junction. As a result a southbound driver failing to realise the realignment of the route may continue on the old alignment and collide with a northbound vehicle or with a pedestrian using the crossing. Pedestrians will be crossing a one-way link and will not expect vehicles to travel in this direction. Recommendation The island between northbound and southbound traffic on Church Road should be modified to obstruct the existing southbound view along Church Road. Supplementary Designer’s Response Island modified accordingly – refer to Arup drwg. no. FP-7000-05.

1.5.7 FP26 – Accesses on Church Road Problem There are two existing vehicle accesses south of the British Legion Club on Church Road, providing access to the field and yard behind. Both may be used by large vehicles and the realignment of the road will make left turns more difficult. Left turning vehicles may intrude into the opposing northbound lane of Church Road

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

Recommendation See items FP7 and FP25. Accesses here to be considered in amended design. Supplementary Designer’s Response Island modified accordingly – refer to Arup drwg. no. FP-7000-05.

1.5.8 FP27 – Pedestrian Crossing on Northbound Exit of Church Road Problem On the northbound exit of the junction on Church Road there are 2 lanes at the stop line of the pedestrian crossing whereas downstream of the crossing there is a rapid reduction to 1 lane. This co-location of the two features increases the likelihood of conflicts between merging traffic downstream of the crossing point and may result in lane changing as drivers travel through the pedestrian crossing. This could lead to drivers failing to stop. Pedestrian flows are likely to be low at most times, so the crossing is likely to be used infrequently. This also could lead to drivers failing to anticipate the signal changing to red. A driver in lane 2 downstream of the crossing who is struggling to merge with heavy traffic in lane 1 could continue across the hatching and into the approaching southbound lane resulting in collisions with southbound traffic. Recommendation As the pedestrian crossing is unlikely to be used frequently it may not be necessary to include 2 lanes at the stop line of the pedestrian crossing. If traffic was merged into a single lane it would improve the safety of the crossing and downstream area. Supplementary Designer’s Response Lane widths / configuration modified accordingly – refer to Arup drwg. no. FP- 7000-05.

1.5.9 FP28 – Kerb Alignment Protrudes into Circulatory Carriageway Problem Adjacent to Wood Lane traffic in lane 3 on the roundabout is guided by hatching before it passes the exit of the bus link. No road markings are shown across the exit of the bus link which means that drivers in lane 3 may clip the dropped kerb at the edge of the maintenance lay-by. This will be more likely to occur as the hatch markings fade. Recommendation Provide edge of carriageway markings on off-side of lane 3 to highlight the alignment. Supplementary Designer’s Response

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

Layout modified accordingly – refer to Arup drwg. no. FP-7000-05.

1.5.10 FP29 – No Provision Made for Vehicular Access to Substation Problem No provision is shown for the electricity substation on the south side of Church Road, to the west of the proposed maintenance lay-by. This is likely to need infrequent vehicle access but possibly involving large vehicles. Recommendation In conjunction with the lay-by for signal maintenance, make provision for access to the electricity substation. Supplementary Designer’s Response Lay-by incorporated accordingly – refer to Arup drwg. no. FP-7000-05.

1.5.11 FP30 – Narrowed Central Reservation May Not Be Sufficient to Accommodate the Working Width of Road Restraint System Problem The central reservation on Uxbridge Road is shown as being narrowed and realigned under the proposals. This may be insufficient to accommodate an appropriate Road Restraint System. In addition, at the eastern end of this central reservation the island widens to provide deflection and accommodate a pedestrian route. The alignment and terminals of the Road Restraint System in this area must provide vehicle containment without obstructing pedestrians. Recommendation Ensure that a Road Restraint System can be provided with a working width within the kerbed island to prevent intrusion into an opposing traffic lane in the event of a collision. Ensure the Road Restraint System does not obstruct or obscure pedestrians An energy absorbing terminal will be required for westbound traffic. Supplementary Designer’s Response Design Team confirms that a median width is 2m. A minimum width of 1.8m is required to accommodate road restraint system – refer to Arup drwg. no. FP- 7000-05.

1.5.12 FP31 – Possibility of ‘See-through’ Between Bus Gate and Stop Line at Circulatory Problem

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Pinewood Studios Ltd Pinewood, Highway Works Supplementary Road Safety Audit Stage 1 Designers Response

The stop line where the Uxbridge Road entry meets the circulatory carriageway is less than 50m downstream of the bus gate. It is possible that drivers approaching the bus gate in all-purpose lanes looking ahead to green signals may fail to notice the bus gate signals changing to red. This can lead to vehicles overshooting the stop line and colliding with a bus passing through the gate. Recommendation In the detailed design, ensure that the signal heads are designed to minimise the risk of ‘see-through’. Supplementary Designer’s Response Bus gate removed from scheme proposals and substituted with typically bus lane “merge” – refer to Arup drwg. no. FP-7000-05.

1.5.13 FP32 – Existing Pedestrian Access Route Severed by Proposed Scheme Problem The existing pedestrian access route across the central reservation – adjacent to properties number 1 and 1a on Uxbridge Road – includes a stagger in the Road Restraint System (see Figure 7, below). Crossing in this location is difficult and will become more so with the new arrangement. Recommendation A Non-Motorised User assessment – as recommended in item FP11 – should include pedestrian manoeuvres between the north and south sides of Uxbridge Road. Supplementary Designer’s Response The existing pedestrian access route, across central reservation, is proposed to be removed and a new controlled pedestrian crossing installed as part of the signalised roundabout proposals – refer to Arup drwg. no. FP-7000-05.

Figure 7 – Existing stagger in Road Restraint and pedestrian access route across A412 Uxbridge Road

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Appendix D Five Points Technical Note

Pinewood Studios Inquiry Appendix D: Five Points Roundabout Application Scheme Modelling Review

Background In January 2009 a proposal from Pinewood Studios Ltd was submitted by their consultants ARUP to change the road layout at Five Points Roundabout, on the Uxbridge Road, Nr Slough. The proposal would dramatically alter the layout and appearance of the current roundabout, however this was considered necessary to improve the capacity and enable a bus corridor through the roundabout.

Jacobs, on behalf of Buckinghamshire County Council, were required to comment and provided a technical assessment of the submission. The comments can be summarised as below;

 The TRANSYT results including pedestrian facilities, show both AM and PM peaks now with greater degrees of oversaturation than the previous results. It is concerning that with very similar traffic flow data link 100 has increased from 97% to 123% saturation, with a new MMQ of 106 pcus. The revB TRANSYT results indicate longer delays, and yet have not made provision for the effect of the bus gate or the bus lane. It is stated that the effect will be minimal, but it should be modelled, just six buses every hour could disrupt node 40 for 10% of all cycles. If during that disruption the delays incurred were passed onto link 400, (a link already at 100% saturation with a MMQ of 65 pcus) then the additional impact may be significant.  A one size fits all value of 1900 for all saturation values, will not give a true picture of capacity and with borderline values for saturation it is difficult to assess if this is an adequate design or not. Traffic lanes should only be grouped together in a Transyt model when queuing and saturation are of similar values. An assumption has been made that this is the case with these multi lane approaches. To clarify this traffic data should be lane defined to test whether the current approach has over estimated capacity.  The TRANSYT models have utilised phase delays to increase performance, but MOVA can not always use these bonus gains. An assumption is made in the TA that MOVA control will give up to 13% improvement in capacity and if this is to be relied upon then this should be tested more robustly.

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In conclusion the revB Transyt results are inconclusive as yet and it would be prudent to take a cautious approach and expect a more robust model to be provided addressing the concerns raised in this report.

Modified Arup Scheme Layout On Thursday 17th February, an amended design for the Five Points Roundabout, with both LINSIG and VISSIM assessments were issued to Jacobs. In the limited time available, the comments below were produced relating to the LINSIG assessment of the junction layout.

Overview  The AM and PM peaks are still in –ve reserve capacity, with optimistic saturation flows, short inter-greens and no allowance for the delays that will be caused by the cut through. The assessment still shows over-saturation of the roundabout, estimated and only when the true values is realised can they look at potential gains of MOVA.

Layout/drawings of Five Points Roundabout  Uxbridge road is two traffic lanes and a bus lane setback not three infinite traffic lanes shown in model  Church road is a single lane feed leading into two flare lanes not three infinite traffic lanes shown in Model  Pinewood road is a single lane feed leading into flare lanes not two infinite traffic lanes shown in Model  There is provision for a bus cut through to exit within from the centre of the Roundabout, how this is to be achieved needs to be explored.

LINSIG Results analysis;  Phase inter-green Matrix - The timings have made no allowance for a longer inter-green in a high speed situation;  Phase delays - MOVA is unable to use benefits gained from phase delays.  Stage diagrams - There is no stage included for a bus/taxi cut through to exit within from the centre of the Roundabout.

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Appendix E Proposed A412 Road Safety Package

Pinewood Studios Inquiry Appendix E: Supplementary Explanation of the Proposed A412 Safety Measures

As has now been agreed in the Statement of Common Ground the A412 has a road safety record which is the third highest for an A class road across Buckinghamshire and is of growing concern to the Authority. In turn collision numbers will tend to reflect traffic growth and patterns unless measures are taken to change this either through physical means on site or through Road Safety Education, Training and Publicity initiatives. Consequently, it is likely that any significant new traffic generation from the proposals at Pinewood will exacerbate the road safety record along this corridor unless action is taken to address these matters positively.

Finance for this work in the Authority is limited and, as a result, there is no complete pool of remedial schemes and safety initiatives specifically aimed at addressing the issues along the A412. Indeed, the impact of a major development at Pinewood may also in some way change the nature and pattern of historic road safety patterns. Consequently, it is difficult to establish a definitive list of interventions to be used in further discussions with Pinewood.

The Authority would however suggest that a figure of £3 to 5M, or even more, may be an appropriate commitment necessary to deal with the likely safety impacts from the major proposals currently under consideration by Pinewood over the initial 10 to 15 year lifetime of the project. By way of illustration of the type of measures that may be needed to address these impacts and their likely costs, we enclose the following examples of work that the Authority may anticipate funding from this source. The list is intended as indicative only rather than as a definitive listing of what may be necessary. In addition some of these examples may represent a need for repeat expenditure over this sort of extended period as patterns change and settle.

A great many of the type of measures discussed below will require local consultation with residents and emergency services to determine final project scope and cost. In addition any works will require careful coordination and timing to avoid extensive disruption. Consequently, it is suggested that an overall S106 contribution is required with an obligation on the Highway Authority to carry out local consultation and

1 implement all works to address road safety needs along the A412 at any time up to three years after completion of Project Pinewood should this be granted consent.

It may be appropriate to report progress on expenditure and benefits achieved through the TRG mechanism now proposed by Pinewood.

Examples of possible safety measures Safety Fencing provision Slough Boundary to Five Points This measure is required to prevent the incidence of central reserve crossover accidents. This has been a recurrent problem in past years and with the increase in traffic numbers associated with the proposed development there is every likelihood that the problem will become more prevalent. The estimated inclusive cost for 3 km of safety fencing on the central reservation along the majority of this length and to treat the nearside of the carriageway on bends is estimated at £1.2M

A412/ Black Park Road Junction improvement This measure is required to address a current road safety concentration and a preliminary scheme is due to be developed in the 2011/12 financial year although no budget is currently allocated for construction. Initial thoughts are that the junction will be fully signalised with associated general improvement work and high friction surfacing. Final inclusive costs are likely to be of the order of £0.5M

Puffins/Toucans x2 through Iver Heath and infill of missing footway links to ensure adequate footway provision from Five Points to Seven Hills Road. These measures are required to promote a safe environment along this busy route for pedestrians and cyclists very much in keeping with the aims and objectives of the development proposals to encourage mode shift to more sustainable modes. The measures will assist walkers and cyclists generated from the development itself as well as those associated with the existing site uses and others within the local community. In addition the measures will help to ameliorate the impact of the considerable additional traffic generated by the development proposals. The measures fit well with the strategy for cycling agreed and supported by the appellant. The estimated cost is :-  Puffins/Toucans £110,000 inclusive  Missing footway links £(not yet available)

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Speed limit review and changes Slough Boundary to Quarry Roundabout to follow the major proposed changes to Five Points and Seven Hills Junction The Appellant is proposing some rationalisation of speed limits in association with proposed changes to Five Points Roundabout. This provides the opportunity for a complete review along this section to ensure overall consistency with the changes proposed at both Five Points and Seven Hills Road and the forecast increases generally in traffic, pedestrian and cycle activity locally. Any changes proposed will need to be enforceable and likely to have a positive influence on road safety. The review outcomes could also be incorporated with Environmental and Traffic Calming measures discussed elsewhere for Iver Heath, Pinewood Green and Fulmer to provide protection against the anticipated increases in general rat running arising from new traffic generated from the development adding to general congestion levels along the A412. The work may involve :-  Undertake review of speed limits along A412 between Slough boundary and Quarry roundabout (approx 5.9km) in accordance with Circular Roads 1/06 Speed Assessment Framework. Review to include data collection (mean speeds, collisions and site information), data analysis, production of report and recommendations – Approx £5,000 - £7,500.  Drafting of amendment traffic regulation orders and associated consultations and legal procedures – Approx £5,000 - £10,000  Preparation of schedule of works to include changes to signing and other traffic management measures as required – Approx £2,000 - £5,000  Possible Works Costs – Approx £35,000 - £100,000 This would suggest a total cost of £47,000 -£122,500 inclusive

Speed activated warning signs on the two approaches to the two new junctions and along the urban section of road through Iver Heath….6 in total These measures are required to influence driver speeds in these sensitive locations to avoid the general worsening in road safety that would be anticipated in line with significant increases in traffic resulting from the development proposals. The estimated cost is £35,000 inclusive

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Review accidents in the wet and renew surfacing---Five Points to Seven Hills  Undertake analysis of wet surface collisions along section to establish any abnormal patterns suggesting surface friction difficulties and prepare report with recommendations on extent of and priority for resurfacing measures – Approx £4,000 - £9,000  Works Costs – Approx £80,000 - £250,000 This would suggest a total cost of £84,000 - £259,000

Lining/ signing review and action  Undertake review of signing and lining along A412 between Slough boundary and Quarry roundabout (approx 5.9km). Review to include data collection (site information), data analysis, production of report and recommendations – Approx £5,000 - 7,500.  Preparation of schedule of works to include changes to signing, road markings and other traffic management measures as required – Approx £3,000 - £6,000  Works Costs – Approx £50,000 - £150,000 This suggests a total cost of £58,000-£163,500 inclusive of fees

Detailed Corridor safety review and recommendations for further measures once any new highway construction associated with the development is complete but before full occupancy  Appraisal of at least 5years collision records along the corridor from Slough boundary to Denham Roundabout to establish any abnormal patterns, trends and groupings. Approx £9,000  Detailed assessment of causation factors to establish possible remedial measures or interventions Approx £5,000  Develop detailed interventions and establish priorities for action Approx £10,000  Works costs inclusive of fees----up to £5M over a 10-15 year period

Support for cross boundary Education, Training and Publicity initiatives to tackle A412 Safety Measures Potentially £50,000 -£150,000 over a 10 year period.

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Appendix F Proposed ITS Package

Pinewood Studios Inquiry Appendix F: Supplementary Explanation of the Proposed ITS Package

This brief note has been prepared following the meeting with Pinewood advisers held on 2 December 2010 where additional information was requested regarding the following items:-  Reconstruction of Pinewood Road  Reconstruction of Seven Hills Road  ITS package of work The latter is discussed individually below and the remainder will be addressed separately.

ITS package The thrust of this element is to seek to build upon the Highway Authority’ s ongoing investment in Urban Traffic Management and Control technology to provide a general environment where users are provided with the best available and up to date information to permit them to make meaningful travel mode and route choice decisions. Overall we need not only to encourage a sustainable travel mix in Pinewood but also to create some space in a similar manner by encouraging a more sustainable mix from existing local people. In particular, as regards the area local to the Pinewood proposals this element will entail:-  A ring of up to 7 Variable Message Signs (VMS) positioned on the local area network at positions where route choice decisions are possible to advise of travel conditions ahead. Unit price inclusive of erection and linkage to the Aylesbury control room is estimated at £20,000 giving a total price of £140,000 exclusive of Vat and professional fees.  Provision of shelters inclusive of Real Time Passenger Information (RTPI) displays at all bus stops within the new development. This is assumed a pre requisite with the high quality services to be provided by Pinewood Studios and is therefore taken as an integral part of the cost of the on-site infrastructure. A full specification can be provided at detailed design stage.  The complexity and size of the proposed Five Points Gyratory will require CCTV cover linked back to the Aylesbury control room. Two installations will be required in view of tree cover and sight lines at an estimated unit cost of £20,000 giving a total of £40,000 exclusive of Vat and professional fees. Any

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alternative signalised proposals for the junction with Seven Hills Road would incur a minimum of one such camera installation subject to detail. Again it is assumed that this element would be an integral part of a new major signal installation and assume that this, or similar, will have already allowed for.  Whilst the junction operational control strategy is still uncertain, local/strategic control Mova/Scoot and for associated comms links to the controllers, which will be resolved through detailed design, should be allowed for.  We have also discussed the potential need for Pinewood to bring forward some degree of traffic calming along certain junction approaches where you are reliant on achieving a lower design speed. This may involve ITS devices such as speed triggered message signs, speed cameras etc  We have also talked at length about real time monitoring of traffic levels. Quite clearly this would involve additional ITS investment should this option be taken forward

10/12/2010

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Appendix G Proposed Traffic Calming and Environment Enhancement Package

Pinewood Studios Inquiry Appendix G: Supplementary Explanation of the Proposed Traffic Calming and Environmental Improvement package

This element of the suggested mitigation package has been addressed from the perspective of giving further protection against the impacts of additional traffic and traffic rat running which may arise as a direct result of the inevitably increased general network congestion arising from the proposed development. Three areas have been addressed:-  Fulmer Village  Pinewood Green  Iver Heath In all three cases the Authority’s ideas are conceptual only at this stage as these measures will need to be the subject of extensive local consultation as an integral part of developing final schemes. In addition, the nature of any final schemes may require statutory advertisement procedures. The concepts are as described below and very preliminary budget costs have been supplied.

Fulmer Village Gateway treatments combined with a lower speed limit (possibly down to 20mph) supported by speed cushions to reduce vehicle speed and volumes through this sensitive environment. Budget cost is £145,000 inclusive of all professional design, consultation, legal, works and supervision costs.

Pinewood Green Area The area is already extensively trafficked calmed to address long standing “rat running “concerns. The concept is to build upon this past investment by the introduction of additional features such as raised table junctions and some additional speed cushions and to cover the entire area of sensitivity with a 20 mph zone. Budget cost is £150,000 inclusive of all professional design, consultation, legal, works and supervision costs.

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Slough Road and Bangors Road North, Iver Heath The concept is to create a 20 mph zone within the built up heart of Iver Heath supported by speed cushions and raised table junctions. The concept would also incorporate some footway resurfacing to create a local much more pedestrian friendly environment than at present. Budget cost is £470,000 inclusive of all professional design, consultation, legal, works and supervision costs.

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Appendix H Proposed Wider Bus Package

Pinewood Studios Inquiry Appendix H: Supplementary Explanation of the Proposed Wider Passenger Transport package

The BCC suggested mitigation package proposed a series of interlinked measures to improve the wider bus offering across the local area both to make best use of the new services proposed by Pinewood and to create a wider sustainable transport environment. In turn the latter would help to reduce car dependency locally and to create the spare network capacity necessary to absorb the additional transport impacts from the proposed development.

Aside from the additional services being funded by the development there are 6 bus stops in Iver Heath. These would benefit enormously from replacement bus shelters and installation of Ibis real time display units. These would be used by both the new routes to the development and also other existing services. Buses on existing routes are already fitted with real time kit and buses on the new services being funded by Pinewood will need to be fitted in the same way as already agreed in principle. Taken collectively this investment in providing the levels of quality service now required by discerning travellers to encourage mode shift from the car will provide a step change in bus provision locally. It will also provide the basis for the levels of patronage needed to support the development’s sustainable aspirations as well as long term commercial bus services

Costs are approximately £6000 per shelter and £6,000 per Ibis unit. I believe we would want 6 of each for the Iver Heath area, excluding those already being provided for the new development itself suggesting a total of £72,000

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Appendix I Extracts from TA 79/99 Traffic capacity of Urban Roads

Chapter 3 Volume 5 Section 1 Determination of Urban Road Capacity Part 3 TA 79/99 Amendment No 1 3. DETERMINATION OF URBAN ROAD CAPACITY

3.1 Table 1 sets out the types of Urban Roads and the features that distinguish between them and affect their traffic capacity. Tables 2 & 3 give the flow capacity for each road type described in Table 1.

3.2 Table 4 gives the adjustments when the proportion of heavy vehicles in a one way flow exceeds 15%. A heavy vehicle is defined in this context as OGV1, OGV2 or Buses and Coaches as given in the COBA Manual (DMRB 13.1 Part 4, Chapter 8).

3.3 The flows for road type UM in Table 2 apply to urban motorways where junctions are closely spaced giving weaving lengths of less than 1 kilometre. Urban motorways with layout and junction spacing similar to rural motorways can carry higher flows and TA46/97 “Traffic Flow Ranges for Use in the Assessment of New Rural Roads” will be more applicable.

3.4 Flows for single carriageways are based upon a 60/40 directional split in the flow. The one-way flows shown in Table 2 represent the busiest flow 60% figure.

3.5 The capacities shown apply to gradients of up to 5-6%. Special consideration should be made for steeper gradients, which would reduce capacity.

3.6 On-road parking reduces the effective road width and disrupts flow, e.g. where parking restrictions are not applied on road type UAP2 the flows are likely to be similar to UAP3 where unrestricted parking applies, see Table 1, Similarly effective parking restrictions can lead to higher flows.

3/1 May 1999 Volume 5 Section 1 Chapter 3 Part 3 TA 79/99 Amendment No 1 Determination of Urban Road Capacity

Two-way Single Carriageway- Busiest direction flow Dual Carriageway (Assumes a 60/40 directional split)

Total number of Lanes Number of Lanes in each direction

2 2-3 3 3-4 4 4+ 2 3 4

Carriageway 6.1m 6.75m 7.3m 9.0m 10.0m 12.3m 13.5m 14.6m 18.0m 6.75m 7.3m 11.0m 14.6m width

UM Not applicable 4000 5600 7200

UAP1 1020 1320 1590 1860 2010 2550 2800 3050 3300 3350 3600 5200 * Road type UAP2 1020 1260 1470 1550 1650 1700 1900 2100 2700 2950 3200 4800 * UAP3 900 1110 1300 1530 1620 ****2300 2600 3300 *

UAP4 750 900 1140 1320 1410 ********

Table 2 Capacities of Urban Roads One-way hourly flows in each direction

Notes 1. Capacities are in vehicles per hour. 2. HGV ≤ 15% 3. (*) Capacities are excluded where the road width is not appropriate for the road type and where there are too few examples to give reliable figures.

May 1999 3/2 Chapter 3 Volume 5 Section 1 Determination of Urban Road Capacity Part 3 TA 79/99 Amendment No 1

Carriageway width 6.1m 6.75m 7.3m 9.0m 10.0m 11.0m

2 lanes 2-3 lanes 3 lanes

Road type UAP1 2950 3250 3950 4450 4800

UAP2 1800 2000 2200 2850 3250 3550

Table 3 Capacities of Urban One-Way roads, hourly flows

Notes 1. Capacities are in vehicles per hour. 2. Capacities for one way road types UAP1 at 6.1m width, UAP3 and UAP4 are not shown as there are too few examples to give reliable capacities. 3. Capacities for one-way roads (e.g. UAP2 at 7.3m and 11.0m carriageway widths) are generally less than capacities of dual carriageways in one direction shown in Table 2. The reason is that one-way roads are often of short lengths and form part of a gyratory system between junctions, necessitating high proportion of vehicle weaving and stopping, thereby decreasing the capacities.

Total reduction in flow level (vehs/hr)

UM and UAP dual Single carriageway Single carriageway Heavy Vehicle carriageway road UAP road having width UAP road having Content of 10m or wider width less than 10m

per lane per carriageway per carriageway

15 - 20% 100 100 150

20 - 25% 150 150 225

Table 4 Reduction in flow due to Heavy Vehicle Content

3/3 May 1999