Hyde House, Pinewoods Road, Longworth, Oxfordshire OX13 5HH

22 September 2004

Dear Mr Clark

Effects of Heavy Lorries Transporting Sand on A420 Traffic & Road Safety

Hanson plc has informed the Oxfordshire County Council (OCC) that it intends to seek planning permission to extract sand from a site in Longworth (see attached map). This proposal will cause serious risks to road safety, and reduce traffic flow. While you cannot assess the case in detail until it is submitted, I would like to learn about the process that you will follow to assess Hanson's proposal when it is made.

Proposal for Sand Extraction

Hanson plans to extract soft sand from a field at the junction of the A420 and Pine Woods Road, Longworth (my neighbour John Phillips wrote to you on 20 July on this subject: he has not yet received a reply, and this letter should broaden your investigation).

Hanson has said that it plans extraction of 125,000 tonnes per annum for ten years, i.e. an average of 2,500 tonnes per week, or 500 tonnes per day. If a lorry or truck can carry say between 20 or more tonnes per trip, this would require an average of 25 arrivals and 25 departures per day, and thus even more at peak periods. Moreover, Hanson intends to sell sand from this site, and so there could be other lorries coming and going, over which little control could be exercised.

Hanson has told local residents that it will propose that all lorries will leave the site by driving south in Pine Woods Road, and then left on the eastbound A420, even if the lorry is destined for Swindon (in this case, it would turn at the A420/A415 roundabout, and return on the westbound A420.

A420 at Longworth

The A420 is at this point a dual carriageway, with two lanes in each direction. For eastbound traffic, this is the first piece of dual carriageway since Swindon (around 14 miles). Any lorry, truck, or other slow moving vehicle therefore collects behind it a string of cars that are eager to overtake it. These faster vehicles use this stretch of the A420 to overtake, frequently travelling far in excess of 70mph.

As a consequence, the mix of traffic is frequently heavy goods vehicles in the inside lane with faster cars overtaking them (and thus preventing the HGVs from moving into the outside lane to allow a slow vehicle from turning out of Pine Woods Road). This can occur throughout the day, because no matter what time of day one lorry coming from Swindon has 14 miles in which to collect drivers behind it.

This junction has no merging or diverging (acceleration/deceleration) lanes to assist exiting or entering Pine Woods Road. Vehicles turning into the A420 thus enter the carriageway by pulling away from stationary, and vehicles leaving the A420 have to slow to a speed to make a right angle turn.

Vehicles trying to join the A420 in either direction are thus faced with a stream of traffic, even heavier at rush hour. Cars can get into the flow of traffic only by waiting and selecting their moment, and then accelerating hard to enter the traffic flow with the minimum danger. John Phillips pointed out in his letter that the slight leftward bend of the eastbound A420 at this point serves to hide some the overtaking vehicles behind the slower HGVs.

Note also that the westbound A420 is the last stretch of dual carriageway before Swindon, and thus many cars are making their final burst of speed to overtake other vehicles. Again they are frequently well in excess of the speed limit.

Effects of Hanson's Proposal on Traffic

Hanson's proposal is therefore for a series of vehicles laden with tens of tonnes of sand to try to turn into this flow of traffic. Such vehicles will accelerate only very slowly - and even more slowly than the average HGV. To avoid causing a collision, they will have to wait for an unusually long gap in traffic flow. For an empty HGV, this could mean a wait of several minutes, but for a lorry laden with 20 or more tonnes of sand this would mean an extensive wait. A sufficient gap might not arise at all during the rush hour for example.

Given the layout of this junction, a lorry waiting would totally prevent any other vehicle, including any car, from getting into the shorter gaps that come more frequently. Also as Pine Woods Road is part of a bus route between Oxford and Swindon, this would hold up the bus for long periods - obviously conflicting with the OCC's Transport Policy.

Lorries arriving at the site from either direction of the A420 would also add to the hazards of the junction. Cars have to slow to below 30mph make the right angle turn into Pine Woods Road; but lorries coming from the west have to slow down to around 15mph (a neighbour who frequently drives a horse lorry can vouch for this figure). And lorries from the east would have to move into the "fast" lane, just at the point where cars are making their final bursts of acceleration on the dual carriageway.

This proposal would therefore cause frequent blockages for traffic wishing to join the A420. It would also increase driver irritation and frustration, which will increase the risk of accidents, at what is already a junction with a record of fatal accidents. The arrival of the lorries into Pine Woods Road will thus increase the hazards of the junction.

Accident Record at this Junction

The junction was created as part of the new Kingston Bagpuize bypass (opened in early 1993). On 8 February 1995, I wrote to the Vale of White Horse District Council warning of the danger of this junction, and suggesting changes to improve safety. The matter was passed to the OCC. The County Engineer's Department reply of 28 April 1995 explained that the records showed only two personal injury accidents at the junction, and that the criteria for improvements were not met. And hence no action was going to be taken to improve the junction.

This was most regrettable as, tragically, there was a fatal accident at the junction later in 1995, and another fatal accident three years after that. The OCC's records show two further personal injury accidents in the past five years, and your colleague informed me that the recorded statistics were probably only half of the real figure.

It is established beyond doubt that the junction already has a bad accident record (two fatal accidents at one spot cannot be described as anything else). Action that would increase the accident rate at this junction would be irresponsible on the part of the OCC or any other relevant authority, as well as being totally unacceptable to residents.

My warning in 1995 of the dangers of this junction did not lead to any change in the junction. I take no satisfaction in observing that my warning came true. And I have no desire to see my second warning of the danger of further fatal accidents come true. But it is abundantly clear to those of us who are familiar with this junction that Hanson's proposal would significantly increase the dangers at this already dangerous junction.

I write on this subject as someone who has more than passing knowledge of the subject: in 1993 and 1994 I conducted a comprehensive review of the Traffic Police of England & Wales, and the Home Office published the ensuing report (Traffic Policing: Activity & Organisation, Police Research Series, 1994).

Conclusion & Way Forward

It is clear that any proposal to route a long series of slow moving vehicles through this junction in the way that has been suggested would be dangerous. I cannot see how Hanson's proposal could be acceptable to the OCC, unless you were willing to ignore a significant increase in the danger to Oxfordshire's road users.

You will probably receive an application from Hanson in the near future. As this subject is important, I would like to learn about the process by which you and your department will apply your professional expertise to judge any proposal. Specifically:

1. Do you have data on the traffic volumes on this stretch of the A420? If so, could you please share them with me? I noted that a traffic survey was being conducted today at this junction: can you confirm whether this was being conducted for the OCC?
2. Do you have data on the length of time and distance that a lorry with a 20 or 30 tonne load would take to accelerate up to the average speed of the A420 traffic? Again, could you share that data with me?
3. What are the criteria that you will use to judge an application from Hanson?

I am very much looking forward to your reply.

Yours sincerely

Adam Ogilvie-Smith