A24 HOP OAST ROUNDABOUT

Transcription

1 A24 HOP OAST ROUNDABOUT SOUTHWATER, WEST SUSSEX COMPLETED S278 HIGHWAY WORKS Road Safety Audit Stage 3 - Completion of Construction November 2018 Report reference 1862

2 CONTENTS page 1. Introduction 3 2. Items raised at Previous Road Safety Audits 5 3. Items raised at this Stage 3 Road Safety Audit 6 4. Audit Team Statement 13 Appendix A List of Drawings & Documents Examined 14 Appendix B Key Plan 15 TED SMITH Traffic Safety Consultant Tele Mob C:/BerkeleyHomes(S)/Glanville/Southwater/A24HopOastRoundaboutImprovements/RSA3Report 05/11/2018 Page 2 of 15

3 1 INTRODUCTION 1.1 This report describes the results of a Stage 3 Completion of Construction Road Safety Audit, carried out on the recently constructed S278 Adoptable Highway Improvement Works at the existing A24 Hop Oast Roundabout, located at the junction of the A24 London to Worthing Road with the B2237 Horsham to Worthing Road, Southwater, West Sussex, in connection with Residential Development of Land at the West Side of Worthing Road, Southwater. The Safety Audit was carried out at the request of the Design Organisation, Glanville Consultants Limited, Cornerstone House, 62 Foxhall Road, Didcot, Oxfordshire, OX11 7AD, on behalf of the Client Organisation, Berkeley Homes (Southern) Limited, Berkeley House, Bay Tree Avenue, Leatherhead, Surrey, KT22 7UE. 1.2 The Adoptable Highway Works consist of widening of the Southern Arm of the B2237 Worthing Road at the northbound approach to the existing roundabout, in order to create space for a dedicated northbound left-turn lane at the junction with the A24 northbound dual carriageway, combined with an increase to three lanes of the existing two lane A24 southbound dual carriageway approaching the roundabout. In addition, modifications were carried out to the existing Northern Arm of the B2237 Worthing Road to widen the carriageway northbound and also to increase southbound capacity approaching the roundabout, whilst some localised widening works at the A24 northbound entry point at the south side of the roundabout are also undertaken. 1.3 The Road Safety Audit Team membership comprised as follows: Ted Smith, CoC Martin Brownsey, BSc, DipEM, MCIHT, CoC Director, MB Projects Ltd Traffic Safety Consultant Highways Consultancy Each member specialises in Highway Safety and Traffic Engineering and have operated independently of the design team responsible for the scheme and have had no involvement with the design of the proposals. 1.4 This Audit was carried out in the offices of the Team Members during September and November 2018, comprising of an examination of the drawings and documents listed in Appendix A, in accordance with various s from Berkeley Homes (Southern) and Glanville Consultants. An inspection of the substantially completed site works was undertaken together during daylight conditions on the early afternoon of Thursday 13 th September 2018, during which time it was clear and dry. Whereas traffic flows were light to moderate, no pedestrians or cyclists were seen in the nearby vicinity. C:/BerkeleyHomes(S)/Glanville/Southwater/A24HopOastRoundaboutImprovements/RSA3Report 05/11/2018 Page 3 of 15

4 1.5 During that daylight site inspection the Audit Team were also accompanied by Ian Jeffery, representing Sussex Police as an Accredited Senior Investigating Officer for Investigating Road Deaths, together with David Lambert and Sean Banaghan, representing West Sussex County Council Highways and Graeme Turner and Alan Bowman representing Granville Consultants. 1.6 A further site inspection of previously outstanding works and conditions was undertaken during darkness on the late evening of Thursday 1 st November 2018, during which time it was cold, damp and misty, whilst traffic was light no pedestrians or cyclists were seen in the near vicinity. Various road safety related identified items identified at that later inspection are included in Section 3 below. 1.7 The terms of reference of the Road Safety Audit are as described in HD 19/15 (DMRB Volume 5: Section 2, Part 2) and the incorporated categories of checklists, as appropriate. The Road Safety Audit Team has examined and reported only on the road safety implications of the scheme as constructed and presented in the drawings listed in the Appendix to this report, and has not examined or verified compliance of the design with any other criteria or standard. 1.8 The object of this Audit is to identify any road existing safety related problems that may be exacerbated or any new problems that may be introduced by the proposed highway works. A previous Combined Stage 1 and Stage 1 Road Safety Audit Report and Designer s Response Report, together with subsequent Interim Stage 3 Inspection Report of substantially completed works were available for reference as part of this current Stage 3 Audit. 1.9 The Designer for this scheme reported at the previous Combined Stage 1 and Stage 2 Detailed Design that five Departures from Standard that primarily appear related to the existing roundabout design and described as such conditions will not be worsened due to the works and those have apparently been approved by West Sussex County Council Highways Authority, with associated comments relating to provision of visibility screening at specific locations as currently indicated on the design drawings All problems and recommendations identified in this report are considered to be of sufficient importance to warrant attention and each are individually referenced and indicated on the Key Plan at Appendix B. ** ** ** ** ** ** ** C:/BerkeleyHomes(S)/Glanville/Southwater/A24HopOastRoundaboutImprovements/RSA3Report 05/11/2018 Page 4 of 15

5 2 ITEMS RAISED AT PREVIOUS ROAD SAFETY AUDITS 2.1 The road safety aspects of the Previous Combined Stage 1 and Stage 2 Detailed Design Road Safety Audit Report number 1629, dated 29 th June 2016 for S278 Highway Works for the Roundabout Improvements and the subsequent Designer s Response Report dated July 2016 were available for reference in this current Stage 3 Audit Report. Whereas most items identified at that time appeared resolved in the subsequent construction, as some features were found to be incomplete during the initial daylight inspection, the required darkness inspection was deferred until those works would be completed. 2.2 Following recent notification of completion of outstanding items consisting of some road markings, installation of road studs and the Lighting Column 19, the subsequent inspection during darkness conditions identified a number of items which combined with items identified at the previous daylight inspection and listed within the previous Interim Stage 3 Inspection Report, now form the basis of this finalised Stage 3 Road Safety Audit Report. ** ** ** ** ** ** ** C:/BerkeleyHomes(S)/Glanville/Southwater/A24HopOastRoundaboutImprovements/RSA3Report 05/11/2018 Page 5 of 15

6 3 ITEMS RAISED AT THIS STAGE 3 ROAD SAFETY AUDIT 3.1 GENERAL PROBLEM (Drawing Ref: /6400 Rev A9) Location: (A) A24 Northbound Left Slip Lane. Summary: Risk of loose gravel entering the carriageway. Immediately behind the recently constructed kerbline the nearside verge area has been surfaced with loose gravel. Consequently, any vehicles attempting to stop partially on the verge area in emergencies, may when subsequently returning drag loose gravel onto the carriageway surface, whereby risk of flying stones may become a serious hazard to other road users. The current area of loose gravel should be removed or sufficiently raked back from the kerbline and the area replaced with soil and grass seeding to form a standard grass verge area PROBLEM (Drawing Ref: /6400 Rev A9) Location: (B) Drainage ditch at west side of A24 Northbound Left Turn Lane Merge Summary: Risk of potential collision with weir structure. At the nearside edge of the lane a lengthy surface water drainage ditch is interrupted by the base of a weir arrangement to restrict flow of water beyond. Since that structure is formed of concrete abutments, concern was raised, especially by the Police representative, that owing to the possibilities of being weather sensitive, any vehicle losing control at the merge, especially during any adverse weather/environmental conditions may errantly enter the ditch and may collide with that structure. Following completion of the feature, it was inspected again during the latest darkness inspection and the resultant formation of mitigating earth works appeared to have suitably modified conditions and thus as situated below the carriageway/verge level, now appeared to be no worse than headwalls within ditches that can be found elsewhere alongside roads in the rural area. The proposed weir arrangement may need to be monitored during the forthcoming maintenance period to determine if any difficulties arise in that period. C:/BerkeleyHomes(S)/Glanville/Southwater/A24HopOastRoundaboutImprovements/RSA3Report 05/11/2018 Page 6 of 15

7 3.2 LOCAL ALIGNMENT PROBLEM (Drawing Ref: /6400 Rev A9) Location: (C) B2237 Worthing Road (Southern Arm). Summary: Risk of errant vehicle passage to rear of safety barrier. Whereas a safety barrier has been erected around the outer radius of the realigned bend, its starting point is located at the far side of an existing low kerb height/hard surfaced crossover to an existing field access, whilst also coinciding with the start of steep down gradient embankment. Since it is so wide open behind the barrier, there appears risk of vehicles passing behind the barrier and down the embankment. The view of the Sussex Police representative, as an Accredited Senior Investigating Officer for Investigating Road Deaths, emphasised his opinion that in the event of icy weather and any subsequent salting works being diluted by following rainfall, any subsequent re-icing may give rise to vehicles possibly skidding, over-correcting and losing control and leaving the carriageway on the nearside. Possible consequences may result in collision with the collapsible end of the safety barrier or a worse scenario of passing to the rear of the terminal point and travelling down the embankment to the fence line below, whereby serious occupant injuries may result. The current arrangements of the low level hard surfaced field access and the wide open approach to the steep embankment behind the current safety barrier should be revisited, possibly in consultation with the Adopting Highway Authority, to investigate/determine a safer manner of preventing vehicles errantly passing to the area behind the safety barrier and subsequently down the embankment PROBLEM (Drawing Ref: /6400 Rev A9) Location: (D) B2237 Worthing Road (Southern Arm). Summary: Risk of serious injuries to motor cycle riders/passengers. The safety barrier as provided around the outer radius kerbline of the bend is currently devoid of any infill panel protection for errant motor cyclists, who may unfortunately lose control on this high risk curvature and in adverse weather conditions may leave the carriageway and collide with the posts supporting the top rail of the barrier. Consequently, concern arises that serious life changing injuries to such users may result. This safety related problem for motorcyclists was previously identified at paragraph of the Combined Stage 1 & Stage 2 RSA Report and recommendation given to infill the space beneath the top rail of the proposed safety barrier, but not carried out. The current situation of exposed posts beneath the safety barrier should be revisited in consultation with Adopting Highway Authority to investigate/determine addition of appropriate protection system to minimise risk of serious injuries to motorcyclists. C:/BerkeleyHomes(S)/Glanville/Southwater/A24HopOastRoundaboutImprovements/RSA3Report 05/11/2018 Page 7 of 15

8 3.3 JUNCTIONS PROBLEM (Drawing Ref: /6409 Rev A8) Location: (E) B2237 Worthing Road (Southern Arm), at the junction with A24 Circulatory Area. Summary: Risk of two-lane entry within wide single lane. The current single lane entry at/approaching the Give Way line is very wide and whilst not marked as two lanes, some drivers were seen forming two separate lanes at the entry to the roundabout, to potential detriment of adjoining driver s visibility of approaching circulatory traffic, whereby collisions with such traffic may result. The current wide lane and driver behaviour at the entry point may need to be monitored during the forthcoming maintenance period to determine whether any mitigation measures may be needed. 3.4 NON MOTOR VEHICLE PROVISIONS PROBLEM (Drawing Ref: /6409 Rev A8) Location: (F) A24 Northbound Exit from the Roundabout. Summary: Risk of Pedal Cyclists failure to perceive access to northbound route. Northbound pedal cyclist s view of the nearside kerbline of the physical splitter island is partially hidden in the low point of crossfall and thus may not give clear guidance to the access gap leading into the left-slip lane for northbound cycle route. Low height delineation posts should be provided on the island to more clearly identify the feature and better guide cyclists to the gap to pass through into the left-slip lane and avoid the northbound A24 traffic merge ahead. 3.5 SIGNS, ROAD MARKINGS AND STREET LIGHTING PROBLEM (Drawing Ref: /6409 Rev A8) Location: (G) A24 Southbound Dual Carriageway, approaching the roundabout. Summary: Risk of inadequate lane information. The advance lane information sign, reference 11 is currently situated to the left of the slip road leading into the Service Station and thus far to the left of southbound driver s forward visibility and partially hidden by the overgrown hedgerow. Consequently, the sign may not be clearly seen by southbound drivers and/or be misunderstood and errantly interpreted to indicate the left turn arrow as directing drivers into the lane leading to those premises, instead of the new left turn lane ahead at the roundabout. C:/BerkeleyHomes(S)/Glanville/Southwater/A24HopOastRoundaboutImprovements/RSA3Report 05/11/2018 Page 8 of 15

9 The current sign ref 11 should be removed and be interchanged with the current position of the temporary sign reference 12, directly in front (north side) of the lighting column numbered 30, (directly in southbound driver s forward visibility). In addition, the existing overgrown hedgerow should be cut back to provide clearer visibility alongside the slip road, whilst the 100 yard countdown sign previously provided on the nearside verge should also be re-erected PROBLEM (Drawing Ref: /6409 Rev A8) Location: (H) A24 Dual carriageway, at the southbound approach to the roundabout. Summary: Risk of insufficient guidance approaching the roundabout. At page 3 of the Designer s Response to Problem (Location G) relating to southbound road markings, a bifurcation arrow to provide better lane guidance was shown to be provided at the separation of the nearside left turn lane and the central ahead lane. That arrow has not been provided as proposed and the current wide open space may be misleading. During the site inspection it was noted that some southbound drivers appeared to be straddling those two lanes and then shifting direction into the central lane, seemingly as if uncertain as to actual position required to travel straight ahead at the roundabout. The proposed bifurcation arrow to TSRGD Diagram 1039 should be implemented in the open carriageway space identified above and possibly the actions of drivers approaching the roundabout may need to be monitored for the forthcoming Maintenance Period PROBLEM (Drawing Ref: /6409 Rev A8) Location: (I) B2237 Worthing Road (North-Eastern Arm) Summary: Risk of unsuitable sign location. The existing Park & Ride sign is in poor position relative to the modified lane layout beyond. In addition, the left turn arrow is missing from the left turn lane adjacent to the right turn bifurcation arrow. One driver was seen to drive straight ahead northbound from within the left turn lane. A left turn arrow to TSRGD Diagram 1038 should be applied adjacent to the northern most bifurcation arrow as shown on the Sign drawing, whilst an additional pair of ahead and left turn arrows to Diagram 1038 should be applied approximately midway between the two current bifurcation arrows to more clearly give guidance approaching the signals ahead. In addition, the existing Park and Ride sign should be relocated further northwards, possibly to the tangent point of the nearside radius kerbline. C:/BerkeleyHomes(S)/Glanville/Southwater/A24HopOastRoundaboutImprovements/RSA3Report 05/11/2018 Page 9 of 15

10 3.5.4 PROBLEM (Drawing Ref: /6409 Rev A8) Location: (J) B2237 Worthing Road (Northern Arm). Summary: Risk of signs not illuminated during darkness. The current two warning signs indicating two-way traffic and traffic signals ahead, (reference number 28W ) includes overhead illumination units that were not working during the darkness inspection, whereby driver information may be missing from the street scene. The illumination of the warning signs should be checked and any defects be rectified PROBLEM (Drawing Ref: /6409 Rev A8) Location: (K) A24 Dual Carriageway, at the northbound approach to the roundabout. Summary: Risk of inadequate driver guidance approaching the junction. The proposed edge line and studs are missing from the offside of resurfaced section of modified carriageway alignment, whilst the existing edge line and studs alongside the nearside lane are badly worn or hidden by detritus. The offside edge line should be provided whilst the existing nearside line should be cleared and refurbished to give clearer driver guidance approaching the roundabout PROBLEM (Drawing Ref: /6409 Rev A8) Location: (L) A24 Dual Carriageway, at the northbound approach to the roundabout. Summary: Risk of inadequate driver guidance approaching the roundabout. The existing chevron sign on the central island facing northbound drivers is damaged and thus suffers loss of clear delineation of the required directional change. The condition of the chevron should be checked and should be replaced or refurbished as found to be required PROBLEM (Drawing Ref: /6409 Rev A8) Location: (M) A24 Dual carriageway and the roundabout circulatory area. Summary: Street lights not illuminated during darkness. The darkness inspection identified several street lights not illuminated, whereby areas of dark shadow resulted. Identified column numbers were 22 and 25 at the east and north sides of the roundabout circulatory area; 28, 30 and 32 at the east side of the A24 Southbound Dual Carriageway alongside the Fuel Filling Station and number 9 on the A24 Northbound dual carriageway just south of the roundabout. C:/BerkeleyHomes(S)/Glanville/Southwater/A24HopOastRoundaboutImprovements/RSA3Report 05/11/2018 Page 10 of 15

11 Each of the identified street lights should be checked and faults rectified as soon as possible PROBLEM (Drawing Ref: /6409 Rev A8) Location: (N) B2237 Worthing Road (Southern Arm). Summary: Risk of inadequate illumination of signs. The current speed limit terminal signs are within the street lit zone, but are currently without illumination units. The current back to back terminal signs should be provided with appropriate illumination PROBLEM (Drawing Ref: /6409 Rev A8) Location: (O) B2237 Worthing Road (Southern Arm). Summary: Risk of large area of carriageway surface without clear markings. Large area of carriageway space is currently devoid of any guidance markings approaching the lane separation on this carriageway curvature, whilst during the darkness inspection no road studs were installed within the marking between lanes approaching the separation. Two additional longitudinal centre line markings between lanes to match existing should be applied in space between the current bifurcation arrow and the start of existing lane markings to give better driver guidance of lane separation PROBLEM (Drawing Ref: /6409 Rev A8) Location: (P) B2237 Worthing Road (Southern Arm). Summary: Risk of inadequate road stud guidance on carriageway curvature. Whereas appropriate coloured road studs have been provided within the central double white line system and also at the hatched area associated with the southbound exit route from the roundabout, whilst studs are also provided within the segregated left turn slip lane starting at the roundabout, suitably coloured studs have not been installed within the lane line separating the northbound ahead lane from the left turn slip lane or the edge of carriageway. Similarly none are provided within the tapered hatched markings approaching the splitter island, whereby overall continuity of suitable guidance is missing. The continuity of guidance by road studs should be revisited and the missing features should be installed to compliment the remainder of the overall junction markings. C:/BerkeleyHomes(S)/Glanville/Southwater/A24HopOastRoundaboutImprovements/RSA3Report 05/11/2018 Page 11 of 15

12 PROBLEM (Drawing Ref: /6409 Rev A8) Location: (Q) B2237 Worthing Road (Southern Arm). Summary: Risk of signs not illuminated. The current warning signs indicating two-way traffic and bend ahead, together with Ending of Clearway, (reference numbers 65W and 67W respectively), both include overhead illumination units that were not working during the darkness inspection, whereby driver information may be missing from the street scene. The illumination of the warning signs should be checked and any defects be rectified PROBLEM (Drawing Ref: /6409 Rev A8) Location: (R) A24 Northbound carriageway, prior to the merge arrangements. Summary: Risk of insufficient warning of traffic merge ahead. During the site inspection discussions of potential safety related problems that may arise at the new merge conditions on the existing A24 northbound carriageway. It was noted that currently there is no indication given to warn northbound drivers that traffic will be merging from the left ahead. Consequently, it was felt that warning may need to be provided now instead of waiting to determine results of any future monitoring during the forthcoming maintenance period. Appropriate warning signs to TSRGD Diagram should in consultation with the Adopting Highway Authority be provided to warn drivers of the merge ahead, possibly in similar circumstances to the recently constructed arrangement at Broadbridge Heath, as shown on photograph below. If actual merge difficulties arise over the maintenance period, then appropriate green faced informatory signs may also need to be later incorporated. ** ** No further road safety related items are identified at this Stage 3. ** ** C:/BerkeleyHomes(S)/Glanville/Southwater/A24HopOastRoundaboutImprovements/RSA3Report 05/11/2018 Page 12 of 15

13 4 AUDIT TEAM STATEMENT 4.1 We certify that this Road Safety Audit has been carried out in accordance with HD 19/15. ROAD SAFETY AUDIT TEAM LEADER Ted Smith CoC Traffic Safety Consultant Signed Date 5 th November 2018 Tele Mob ROAD SAFETY AUDIT TEAM MEMBER Martin Brownsey BSc, DipEM, MCIHT, CoC Director MB Projects Ltd Signed Highways Consultancy Date 5 th November 2018 Tele Mob C:/BerkeleyHomes(S)/Glanville/Southwater/A24HopOastRoundaboutImprovements/RSA3Report 05/11/2018 Page 13 of 15

14 APPENDIX A LIST OF DRAWINGS & DOCUMENTS EXAMINED Drawing No/Document Date Scale Description /6200 Rev A3 11/07//2016 A1 Vehicle Swept Paths /6400 Rev A9 09/12/2016 A1 General Arrangement /6404 Rev A8 21/09/2016 A1 Surface Finishes /6407 Rev A2 17/06/2016 As shown Construction Details /6408 Rev A8 02/05/2018 As shown Surface Water Drainage /6409 Rev A8 14/02/2016 A1 Traffic Signs /6410 Rev A7 17/06/2016 A1 Road Markings /6411 Rev A3 17/06/2016 A1 Proposed Levels & Contours /6412 Rev A3 17/06/2016 As shown Long Sections SSE AC-001 Rev A 07/03/ Street Lighting Report SSE AC-002 Rev A 07/03/ Street Lighting Report SSE LD-001 Rev C 07/03/2016 A1-- Street Lighting Layout Drawing Sheet 1 of 2 Report July Report of Surface Treatment Superflex 72 Report /07/ Combined Stage 1 & Stage 2 Road Safety Audit Report (Ted Smith) Report TR /GT/024 July Designer s Response Report to above Combined Stage 1 & Stage Audit Report (Glanville) Report 16/09/ Listing of Initial Problems Identified at the Interim Stage 3 Daylight Site Inspection (Ted Smith) s Various dates -- Audit Brief and Instructions (Berkeley Homes (Southern) & Glanville Consultants APPENDIX B KEY PLAN Copy of drawing numbered /6409 Rev A8 C:/BerkeleyHomes(S)/Glanville/Southwater/A24HopOastRoundaboutImprovements/RSA3Report 05/11/2018 Page 14 of 15

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