Highways Agency

INCIDENT AT LITTLE HECK ON 28 FEBRUARY 2001

PRELIMINARY OPINION REPORT

1. Introduction

1.01 A TRL investigation team arrived on site at approximately 1430hrs on Wednesday 28 February 2001. The team included highly experienced specialists in the fields of highway design and maintenance. In particular, this included safety fence and bridge parapet expertise. Other members of the team specialise in the acquisition of incident data using state-of-the-art 3-Dimensional laser scanning technology and this equipment was used to obtain detailed information concerning the accident scene.

1.02 The investigation team liaised with Highways Agency (HA) regional staff and their Maintaining Agents, WSP Civils Ltd. Schedules of documents were requested to be secured by HA/WSP.

1.03 The site was subject to detailed examination, measurements were taken and specialist surveys of skidding resistance and other road surface characteristics were commissioned and then undertaken during the period up to 5 March 2001.

1.04 This report is intended to provide brief preliminary opinion regarding the role played by the highway in accident causation and outcome, based on the information available to date. A full report will be prepared as soon as our investigations are complete.

1.05 The issues investigated include the winter maintenance of the motorway, road surface condition, and safety fence design and construction.

2. Winter Maintenance

2.01 Some initial press coverage referred to the vehicle leaving the motorway in icy and snowy conditions. Study of available documentation, in addition to anecdotal evidence from maintaining engineers who were present on scene soon after the incident, indicates that the road surface was salty at the material time and that there was no ice or snow present on the motorway.

2.02 Therefore, it currently appears that winter maintenance issues are irrelevant in terms of causation. Notwithstanding this, our initial opinion regarding the adequacy of the winter maintenance operations on the motorway during the relevant period, is that they were both adequate and appropriate.

3. Road Surface Condition

3.01 The surfacing history at this site is currently unknown to us. However, visual inspections indicated that the motorway surface at this location is in generally good condition.

3.02 The preliminary results of the skidding resistance and other road condition surveys suggest that the road surface is adequate in all relevant aspects.

3.03 Therefore, our current opinion is that road surface condition probably did not contribute to either accident causation or the severity of its outcome.

4. Safety Fence And Bridge Parapet Issues

4.01 The material vehicle did not strike the safety fence. Therefore, the main issue relating to safety fence provision concerns its length in advance of the bridge parapet.

4.02 The current safety fence standard is TD19/85, which provides criteria for safety fence provision in advance of obstructions. TD 19/85 requires at least 30 metres of full height safety fence in advance of an obstruction.

4.03 BS6779 is the relevant standard for parapet design and Part 3 relates to the design of this type of parapet. However, this standard does not refer to lengths of safety fencing in advance of the parapet.

4.04 BE5 is the technical memorandum referring to parapet requirements. This document is consistent with TD19/85 in that it also refers to a minimum requirement of a 30 metre length of safety fence in advance of the parapet.

4.05 The relevant M62 bridge over the east coast mainline railway exhibits full height safety fence for 33.5 metres in advance of the parapet, plus an additional 9.2 metres of ramp down to anchor, providing a total length of 42.7 metres.

4.06 Therefore, the material safety fence appears to comply with standards in regard to its length.

4.07 In order for the whole of the front of the Land Rover to have engaged with full height safety fencing, the length of full height safety fencing present at the material location would have needed to have been in excess of twice its current length.

4.08 It should be noted that the material vehicle combination (a Land Rover County towing a double axle trailer unit carrying a Renault Savanna estate car) is outside of the vehicle specification for this type of safety fence. Therefore, we cannot be certain at this point in our investigations that the safety fence would have restrained the vehicle, even if it had fully engaged with it.

4.09 Notwithstanding the above, our preliminary opinion is that any engagement between Land Rover and safety fence would have been likely to prevent the vehicle reaching the railway line.

5. Conclusions

5.01 Having investigated the road surface, both in terms of winter maintenance issues and in terms of alignment, profile and skidding resistance, our preliminary opinion is that the road surface condition was adequate and is not believed to have contributed to either the cause of the accident or the severity of its outcome.

5.02 The safety fence was found to be of a length that meets the requirements of national standards. It would have had to have been twice its length at full height to have engaged the whole front of the errant vehicle.

Adrian M E Runacres, TRL Limited

Malcolm D Macdonald, TRL Limited

6 March 2001