Scrutiny Committee



Report of Head of Policy and Programmes

Author: Vicky Aston                                                

Telephone: 01235 422600


Wards affected: Wantage, Charlton


Vale Cabinet member responsible: Cllr Debby Hallett



Date: 17 November 2021



A34 diversion routing

Purpose of Report

  1. This paper has been prepared in response to the motion agreed at Council on 19 October 2019 concerning re-routing arrangements for scheduled closures of the A34 in southern Oxfordshire.  The purpose of this paper is to set out why the A34 is closed during night time hours and what these closures are for.  It will also explain the process for reviewing diversion routes.


  1. Setting diversion routes is not a responsibility of our Council, it is the responsibility of National Highways (previously Highways England) and Oxfordshire County Council.  Representatives for National Highways and Oxfordshire County Council will attend scrutiny on 25 November to provide further information and answer questions from councillors.


Corporate Objectives



  1. Engagement with Oxfordshire County Council and National Highways supports the Corporate Plan 2020-2024 theme ‘Working in Partnership’.





  1. In 2019 the A34 was subject to a series of night closures due to a construction project on the A34 at that time.  These closures, which often operated between 10pm and 6am, re-routed traffic on to the A338 and the A417. As a consequence of the impact of these closures, Council passed a motion. The motion as set out in the minutes of the Council meeting (19 October 2019) states; 


‘Council notes that the re-routing arrangements for scheduled closures of the A34 in southern Oxfordshire are creating a totally intolerable blight on the lives of many of the residents of Wantage, Charlton Ward and further afield. These closures, which typically operate between 10pm and 6am, re-route traffic on to the A338 and the A417. In the 3 months to the end of October 2019 closures will have occurred on 25 occasions. Council further notes that the consequence of these arrangements is to divert very high volumes of traffic, much of it heavy commercial, from a Designated Primary Route to minor roads, occasionally single lane, not considered suitable for heavy traffic in built up residential areas. Residents of impacted houses report that this creates intolerable noise, sleep deprivation and vibration and structural damage to properties, as many of their homes are only a matter of feet away from the highway. Council is also aware that the diversions create significant road safety issues and that damage has occurred to Infrastructure and other vehicles.’


Council is aware that alternatives exist, including re-routing via a designated Primary Route or introducing a contraflow system on the A34 itself. Furthermore, Council is concerned that any future re-routing scheme may be ineffective due to increased use of satellite navigation systems which could risk the use of rat runs.


Therefore, Council requests that the Scrutiny Committee consider including this matter in their work programme, noting that Scrutiny has the power to invite parties such as Highways England, OCC, Thames Valley Police, Kier Group plc and Wantage Traffic Diversion Group to attend any such meeting.’


  1. Diversion routes are agreed by National Highways with Oxfordshire County Council.   A copy of the plan showing the diversion route between Milton Interchange and Botley Interchange (A417 and A338) is attached to this paper (Map 4).  Other maps showing the routes for closures between Chilton and Milton Interchange (Map 5) and for closures between Beedon and Chilton (Map 6) are also attached.



Why are A34 closures required?


  1. There are currently no major works scheduled to take place on the A34 that would require major night time closures.  However, the A34 could still be subject to some night time closures.  A key strategic route like the A34 will usually be resurfaced every 5-7 years.  It should be expected that the route will also be closed for routine maintenance and cleaning, to sweep the road and collect rubbish such as tyres and repair damaged signage.  The agreed diversion routes are also used when there is an accident on the A34 and closure is required. 


  1. The A34 is a key route for HGVs from the Midlands to the ports.  This means that closures for routine maintenance are likely to be more frequent than for some other major routes on the network.   


  1. In addition to being a standard practice, full closure of the route during nightime hours has a number of benefits.  Complete closure allows maintenance workers to undertake their work in safety and complete it more quickly.  Working during nightime hours also reduces disruption during the daytime hours when the majority of traffic uses the route.  Whilst the closure period is usually advertised as 10PM-6AM, if the works can be completed sooner and the route re-opened more quickly, then this will occur. 


  1. National Highways carefully considers the scheduling of any closures for routine maintenance.  For example, bank holidays and any weekends where special events are expected are avoided.  There is a Road Space Booking Team who co-ordinate this at National Highways.  Most works will not be undertaken by a single contractor but rather a contractor with one or more sub-contractors.  For example, one contractor may put out the traffic cones whilst a different contractor will undertake the works.


  1. National Highways are aware that the commonplace use of satellite navigation means that drivers do not always follow the diversion routes and this is a challenge across the network.  Some HGV vehicles use a sat nav that directs them to use the agreed diversion, however, easily available, and often free web based sat nav applications are now widely used and quite understandably, these can lead to drivers ignoring the agreed diversion routes.


  1. The County Council and our Council have no powers to insist that drivers follow the diversions or any set route.  The recent pandemic has increased demand for home shopping and consumer expectation is that goods will be delivered quickly.  Often drivers are incentivised to complete journeys quickly and complete more deliveries, particularly those paid on an hourly basis.  This can lead to increased night time traffic following a wider variety of routes. 


Consultation on alternative diversion routes


  1. Diversion routes are reviewed by National Highways periodically.  A wider nationwide study looking at diversions has recently started a review of diversion routes for the A34 area by area.  This is not starting in Oxfordshire and it is anticipated that this area of the A34 will be looked at in the next 1-3 years.


  1. Oxfordshire County Council has advised that there are few alternatives to the current diversion routes available to support works on the A34.  Diversion routes will usually direct traffic down the next available A road.  National Highways and Oxfordshire County Council advise that shorter diversions are preferable.  The longer the diversion, the more likely it will be ignored and also a longer diversion that encourages significant additional mileage (for example, use of the M4) will increase carbon emissions.


  1. The Council and residents are able to provide suggestions for alternative diversion routes although the decision around the specific route is not ours to make.  A simple annotated route plan can be accepted for consideration by National Highways.




  1. Representatives from National Highways and Oxfordshire County Council are attending scrutiny to answer further questions relating to the process of how diversions are put in place and decided.


Background Papers

Maps showing A34 diversion routes;


·        Map 4 – Area 3 A34 Diversions Milton Interchange and Botley Interchange (A417 and A338)

·        Map 5 – Area 3 A34 Diversions Chilton and Milton Interchange

·        Map 6 – Area 3 A34 Diversions Bi-Directional Beedon and Chilton