
ENVIRONMENT AND COMMUNITIES SCRUTINY COMMITTEE 4 March 2015 INFORMATION REPORT: Congestion on the A40 West Of Gloucester 1.0 Background At the Environment and Communities Scrutiny Committee meeting on 12 November 2014, members asked for a discussion regarding the A40 West of Gloucester, aimed at resolving the congestion experienced on this route, particularly during am peak periods. The A40, from Junction 11 of the M5, west towards the County Boundary, is a trunk road, and is part of the Government’s Strategic Road Network. This means that the Highways Agency (HA), on behalf of the Government, looks after the road, including maintenance and improvement. Traffic flows on the A40 are the second highest in the County, (second only to the A40 Golden Valley Bypass), with high congestion levels. Congestion is experienced most morning peak hours, with queues frequently stretching down the A48 towards Minsterworth and west of Highnam roundabout on the A40. The HA are currently constructing a capacity improvement scheme at the Over roundabout, as part of its ‘pinchpoint’ programme of congestion reducing schemes. This will be completed by the end of March 2015 and is designed to make improvements to the capacity of the roundabout. The following plan, taken from the Local Transport Plan consultation document 2015-2013 (Cabinet version) shows the traffic flows on key routes within the Forest of Dean and shows a flow of 38,508 on the A40 at the Over Roundabout. 2.0 Current Strategy for the A40 The following outlines the current strategy for resolving the congestion issues on the A40. 2.1 Gloucestershire Local Transport Board (GLTB) scheme at Over roundabout In addition to the HA’s improvement scheme above, the County Council is developing a more comprehensive improvement to this junction. As part of the devolution of major scheme funding from central Government to Local Highway Authorities the County Council submitted a bid to the GLTB for an improvement to Over roundabout. The bid was for £2.23m of funding to improve the roundabout and also to investigate the removal of the hatching that is currently in place at Highnam Lodge. As a result of ongoing discussions with the Highways Agency, about the removal of the hatching, this has now been dropped from the GLTB scheme. The removal of the hatching will be discussed further later in this report. The table below sets out the details of the schemes, which are currently programmed for construction in 2017/18 Location Description of improvement Over Rbt – A40W Signalise the A40W entry to the roundabout, from Ross-on-Wye and circulatory carriageway Over Rbt – A417S Signalise the A417S entry to the roundabout and circulatory carriageway Over Rbt – A40E Widening of the A40E entry to provide three lanes at the stop line Over Rbt – A417N Widening of the A417N entry to provide three lanes at the stop line Over Rbt Adding a third circulating lane on the roundabout Traffic modelling indicates that, without intervention, delays could increase significantly - by up to 156%, on the A40 eastbound approach, AM peak, in a 2022 forecast year compared to a 2007 base (see Tables below). Increased journey times and congestion would have an adverse impact on achieving the LTP goals – in particular, it would constrain the delivery of sustainable economic growth, with deterioration in the quality of strategic transport connections between the Forest of Dean to Gloucester, and beyond. The lack of capacity would act as a constraint to planned growth, compromise the efficient movement of people and goods and have a detrimental impact on the attractiveness of the area to businesses. Access to jobs, including at Gloucester and major employment sites such as Innsworth, would be compromised. As congestion increases, there are also likely to be greater environmental challenges from increased carbon emissions and deterioration in local air quality. The following tables set out the results of the traffic modelling of Over roundabout at a base year of 2007 and a forecast year of 2022, without any improvements made to the roundabout. The table shows the queue on the approach to Over roundabout increasing from 273 to 695 in the am peak, with delay increasing from 9 minutes to nearly 25 minutes. Modelled traffic results at Over Roundabout (2007 base year) Source: A40 Over and Longford Roundabouts: Improvement Assessment Report (2007) Modelled forecast traffic results at Over Roundabout (2022 base year) Source: A40 Over and Longford Roundabouts: Improvement Assessment Report (2007) 2.1.1 Highnam Lodge Hatching The initial scope of the A40 Over roundabout scheme included the removal of lane restrictions at Highnam Lodge, locally known as ‘Linton Lodge hatchings’. These are located on the eastbound A40 (Highways Agency [HA] maintained) between the A40/A48 roundabout and the B4215 junction. The hatchings run for approximately 300m on the inside lane of the dual carriageway. It was believed that the hatchings were originally installed by the HA to allow the safe entry and exit of vehicles from the Linton Lodge residential property owing to the high A40 eastbound approach speeds and poor forward visibility (or stopping sight distance) offered by the left lane. By hatching out a section of this nearside lane and forcing all traffic into the adjacent offside (right) lane, a greater forward visibility distance is attained which is more suited to the speed of road. However, more recent research, including a meeting with the owner of Linton Lodge (22/10/14) and further conversation with the HA, has revealed that this A40 nearside lane hatching was in existence prior to Linton Lodge being developed, and continued eastwards past the site access towards the A40/B4215 traffic signals junction. It is now evident that the hatching was originally introduced by the HA for safety reasons, to protect vehicles queuing back from the traffic lights owing to the substandard visibility on the approaching bend in the vicinity of Linton Lodge. Whilst the Linton Lodge access benefits from the hatching, it is not and was never the primary reason for their installation. Removal of the hatching, to allow vehicles to utilise both eastbound carriageway lanes, would require resolution of the afore mentioned forward visibility issues concerning the queue for the B4215 traffic lights as well as access to Linton Lodge. Simply moving the Lodge access to another location along this road section, or providing an additional set of traffic lights at the access (originally promoted as part of the GLTB scheme) is therefore no longer considered a safe or satisfactory solution. Options appraisal Based on current ordinance survey plans, the following options for removal of the hatching may be considered. 1. Provide a forward visibility splay sufficient for the current speed of the road (50mph). This could require the purchase of land. 2. Realign the carriageway by widening into the central reserve, provide a merge lane for the lodge, remove vegetation and reduce speeds to 30mph. 3. Realign the carriageway by widening into the central reserve, provide a merge lane for the lodge, remove vegetation, purchase land, demolish and rebuild Linton Lodge boundary wall, and reduce the speeds to 40mph. All of the above options would have significant budget implications and Options 1 & 3 would require land purchase (and possible CPO should the Lodge owner be unwilling to negotiate on any sale). In addition, an informal discussion with the Police, (as part of the Highways Agency’s A40 Route Congestion Study 2011) suggests that they would be unwillingly to support a TRO to reduce the speed limit to 40mph as it would be difficult to enforce. This is because the existing carriageway is of a high standard and barriers are present. This causes a driver perception that even the existing speed limit of 50mph is unnecessarily low for the road. Furthermore, in recent meetings with GCC Officers, HA representatives have indicated that they are unlikely to support the lowering of the speed limit on the trunk road given its arterial status. On site observations and previous traffic modelling (done by both GCC and the HA) give a high level of confidence that the average eastbound journey time from the Forest of Dean to A40/A417 Over roundabout would not be reduced during the morning peak period by the removal of the hatching at Linton Lodge. This is primarily because vehicle queues currently block back into Highnam roundabout and regularly extend back well beyond the roundabout on both the A40 (towards Birdwood) and A48 (towards Minsterworth) approaches. While the queues would obviously be shorter on the A40 and A48 if the hatching was removed, average journey times would not be reduced as any gaps that occur in this queue for any reason are always filled well before Over roundabout, so the roundabout always operates at full capacity. Previous traffic modelling and observations undertaken both by the GCC and the HA on the A40 corridor from West of Severn towards Gloucester have shown that while delay and congestion occurs at the A40/B4215 traffic signals junction during the AM weekday peak period, the A40/A417 Over Roundabout is the cause of the queues into Gloucester, with traffic regularly blocking back upstream affecting the A40, A48 and B4215. This is due to the insufficient capacity of the existing A40 Over junction, the level of opposing traffic turning movements on key approach arms, the limited junction visibility and poor management of existing traffic movements (lack of road markings, signing etc.). To summarise, at present, contrary to driver perception, the hatching has little to no effect on the vehicle journey times from the Forest of Dean into Gloucester during the morning peak period. However, future capacity improvements to A40/A417 Over Roundabout are planned for early 2015 (HA’s western arm widening scheme) and our proposed scheme for Spring 2017 (GCC’s GLTB Major Improvement Scheme, widening of approaches and possible signalisation), the latter of which should significantly reduce queuing and delays on this route into Gloucester.
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