Agenda item

OS/19/13 Highways England Update on the Orwell Bridge

Minutes:

40.1      Simon Amor, Head of Planning and Development, Highways England, and Roy Doe, Service Delivery Manager, Highways England, gave a presentation regarding the Orwell Bridge. The key points made were:

-       The bridge was an important asset for Ipswich, but was very susceptible to high winds because of its location;

-       Highways England fully appreciated the impact of closures on Ipswich but they had to close it when there was a cross-wind in excess of 50mph, or a wind in any direction of over 60mph to ensure road safety;

-       The time taken to close the bridge had been reduced from 50 minutes to 20 minutes before high winds were forecast to hit;

-       Separating high sided vehicles from other traffic would be difficult to achieve as there was no infrastructure to support this, no resources to enforce it and no welfare facilities for drivers who were not able to cross the bridge;

-       There had been 18 closures, totalling around 5 days, due to wind over the past 7 years;

-       The lower speed limit of 60mph had reduced the number of accidents by 30%.

-       Communications about forecast closures had improved with better co-ordination with the Police, Suffolk County Council and Ipswich Borough Council.

 

40.2      Simon Amor explained that Highways England had commissioned a study by City University, which was a world expert in wind modelling, on the effect of high winds on the Orwell Bridge. The study had shown that there were a number of options available to allow the Orwell Bridge to stay open for longer. These options were:

-       The Orwell Bridge could remain open in higher winds if the speed limit were temporarily reduced, for example, if the speed limit were 40mph the study had shown that the bridge could safely operate in winds of 70mph. The speed limit would however need to be observed and so additional signage would be needed and enforcement would need to be available, likely through the average speed cameras already installed;

-       The nearside lanes on each carriageway could be closed, with the offside lanes benefiting from greater protection from the existing parapets. Closing the lanes would be difficult however as cones may be difficult or impossible to place in high winds and other measures were not easily available;

-       The westbound carriageway could be closed, as this was more severely affected by high winds, with the eastbound carriageway left open.

Further wind tunnel testing would be required to ensure that the options were safe, and various practical arrangements would need to be made, before any of them could be implemented.

 

40.3      Councillor Pope asked whether the existing average speed cameras could be used to enforce a lower speed limit. Simon Amor explained that it was thought that this would be possible but this needed to be confirmed with the Safety Camera Partnership, Suffolk Roadsafe. Superintendent Matthew Rose, Head of Specialist Operations for Norfolk and Suffolk Police explained that he understood that the trigger speed for the cameras could be changed very quickly, although it was also important that drivers were educated about the need to slow down.

 

40.4      Councillor T Lockington noted that separating high sided vehicles appeared to have been discounted as an option owing to a lack of resources. Councillor Lockington asked whether this was right considering the economic impact of closures on the town. Mr Amor replied that whilst resources to separate out high sided vehicles was an issue, the reason this was not a favoured option was that there was no infrastructure available to assist with the separation. In response to a further question from Councillor Lockington Mr Doe explained that width restrictions would not separate out unladen light vans which were as, if not more, vulnerable than HGVs to the effects of high winds.

 

40.5      Councillor Grant asked whether more work could be done on alternative routes avoiding the centre of Ipswich when the Orwell Bridge was closed, either due to wind or an accident. Mr Amor said that further work could be done on advance signage and communications, whilst Graham Mateer, Head of Transport Strategy, Suffolk County Council, explained that whilst routes avoiding Ipswich town centre were available there were also significant issues with these.

 

40.6      Councillor Gage asked that diversion routes be considered in more detail, including Suffolk County Council doing works to potential alternative routes to make them suitable. Mr Amor noted that 55,000 vehicles used the Orwell Bridge each day and that no diversion routes would be able to cope with that volume of traffic. Councillor Gage commented that if a proportion of those 55,000 vehicles were prevented from coming through Ipswich by improving other diversion routes then those improvements would be justified. Mr Amor and Mr Mateer explained that making any significant difference to the alternative routes available would be very expensive and such works could potentially be national schemes.

 

40.7      Paul Simon, Head of Communications and Campaigns, Suffolk Chamber of Commerce, asked whether the Orwell Bridge remained the number one priority for Highways England East, whether it was a priority nationally and what the timescale for implementing a reduced speed limit in high winds was. Simon Amor confirmed that the Orwell Bridge remained the top priority for Highways England East and that it was important to Highways England nationally. Mr Amor explained that he expected that, subject to there being no issues around enforceability, temporary reduced speed limits could be introduced before the Winter of 2020/21.

 

40.8      Paul Simon asked whether additions to the parapets were still being considered by Highways England. Mr Amor explained that the parapets on the Orwell Bridge were an integral part of its structure and so additions to these might be very difficult owing to the stresses placed on the bridge; wind tunnel testing would be completed within the next 12 months and these would determine the amount of protection provided by the existing parapets.

 

40.9      Suffolk County Councillor West, Cabinet Member for Ipswich, Communities and Waste, noted that there was consensus that the proposal for temporary speed limits should be introduced as soon as possible and that all parties should work together to ensure that this happened. Councillor West commented that other work, for example, considering the parapets, should continue but should not delay the introduction of the temporary speed limit scheme. Simon Amor noted that there were statutory processes to be followed around reducing speed limits but said that Highways England were keen to see the scheme implemented as soon as possible. Roy Doe noted that wind tunnel tests would also have to prove that reducing the speed limit would allow vehicles to run safely in higher winds.

 

40.10   Councillor Allen noted that there were also frequent closures of the Orwell Bridge because of accidents and asked whether more could be done to reduce closure times for other incidents. Superintendent Rose explained that a network of recovery operators, which had to meet high standards in terms of capacity and response times, assisted with keeping the Orwell Bridge clear. Superintendent Rose confirmed that police vehicles would normally tow any broken down vehicles off of the A14 to a place of safety if they were able to do so. Where there were crashes involving serious injury or death there would often be a longer road closure as investigation work needed to take place, and the damage was often also more severe.

 

40.11   Councillor P Smart, Portfolio Holder for Environment and Climate Change, noted that the Orwell Bridge was closing due to high winds more frequently, having closed 10 times since January 2018, whereas it had only closed 8 times in the 5 years before January 2018. Councillor Smart commented that this was likely to be due to climate change and that Highways England needed to plan for extreme weather becoming more common, although he agreed that the proposed temporary speed limit reductions would be a helpful measure in the short to medium term.

 

40.12   Councillor P Smart suggested that closing the more vulnerable Westbound carriageway to high sided vehicles might be easier than closing the Eastbound carriageway as most of the traffic would be coming from Felixstowe port where there were facilities for drivers. Mr Amor noted that there would also be heavy goods vehicles travelling from places other than Felixstowe but agreed to discuss the possibility with the operators of Felixstowe Port.

 

40.13   Councillor P Smart asked whether the service station on the westbound carriageway contributed significantly to accidents on the A14 and also suggested that if a further permanent reduction to the speed limit on the Orwell Bridge would reduce the time the bridge was closed due to accidents this ought to be considered. Mr Amor commented that service station slip-road, whilst short, did not contribute to many accidents. Most accidents on the Orwell Bridge were caused by drivers not paying sufficient attention to the road.

 

40.14   A resident noted that the Orwell Bridge was closed for maintenance at night and that the diversion route, which was used by a large number of HGVs, passed close to many homes and kept residents awake. The resident asked whether single carriageway closures and a contraflow could be used or if HGVs could be stacked rather than diverted. Mr Amor explained that bridge maintenance needed to be carried out and that overnight closures were far less disruptive to traffic. Introducing a contraflow was not practical as a certain width of carriageway was needed and even if it were possible to squeeze one onto the bridge the installation and removal of the barriers necessary to make a contraflow safe generally each required a full overnight closure.

 

40.15   A resident commented that Highways England had agreed to look at whether wind baffles could be introduced and that residents had waited too long for this to be done. Mr Amor explained that the Orwell Bridge was a complicated structure and that installing baffles over 1.2km of bridge would create significant structural loading. Mr Amor repeated his hope that the vast majority of closures would be prevented by the introduction of temporary reduced speed limits by the winter of 2020/21.

 

40.16   Councillor Ellesmere, Leader of Ipswich Borough Council, asked whether a list of what needed to happen to introduce temporary reduced speed limits and give timescales for each piece of work. Mr Amor agreed to supply milestones to partners and explained that a stakeholder event was planned for early March to help ensure that implementation could be as swift as possible.

 

40.17   Councillor Gage suggested that Highways England be invited to attend the 9 July 2020 meeting of the Strategic Overview and Scrutiny Committee to report on alternative diversion routes, their work on understanding and potentially amending the bridge parapets, and progress made on implementing the proposal for temporary reduced speed limits in high winds.

 

It was RESOLVED:

 

that Highways England be invited to attend the Strategic Overview and Scrutiny Committee on 9 July 2020.

 

40.18   The Chair thanked all those who had attended to discuss the Orwell Bridge for their contributions and time.

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