A21 Tonbridge to Pembury Dualling

Project status:   Current

Start date:   Spring 2015
End date:  Spring 2017

Type:   Major Scheme
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Major Scheme

Part of our programme of improvements (value >10m)

Cost:  £69.7m (most likely)


Site working hours have now been amended to 7am to 5pm to take into account the changes in daylight hours.

During November the use of the plant crossing of both the A21 and Longfield Road are likely to be significantly reduced.

Construction Work Undertaken in October

Main Construction Activities

Utility Diversions – works along the scheme to facilitate the various utility company pipes and wires is on-going, with the most significant activities being;

Gas - Work to install a new gas main crossing near to Vauxhall Lane was on-going.

Water – Work to provide a new connection in the Vauxhall Lane section of the scheme commenced.

In the central and southern sections of the scheme various utility company services (including BT, UK Power Networks, and Virgin Media) are in the process of being diverted.

Southern section (Pembury to Blackhurst Lane) – Other than the utility works the principal operations in this area during the month were the forming of the northbound sliproads and the western roundabout. Drainage installation also started, along with excavation to create the highway balancing pond.

Central section (Castle Hill to Pembury) – The excavation to form both sides of the new Fairthorne junction continued in October and is now around 90% complete. We also began to create the two highway balancing ponds in this section.

Northern section (Castle Hill to Vauxhall) – The principal activity within this area is the gas main and water main works.

Construction Planned for November

Southern Section (Pembury Walks to south of Longfield Road) – Drainage and preparatory work to create the new western roundabout and both the north and southbound slip roads will continue. Sections of new highway fencing will also be installed.

Central Section (Castle Hill to Pembury Walks) – The drainage along this section and around the new Fairthorne junction will start in the month and the base layer for the actual road construction will begin to be laid.

Excavation works for a temporary road diversion & preparation for the bridge works will recommence when the utility diversions are completed.

Northern Section (Vauxhall to Castle Hill) – As in the previous month the gas main work will continue and will be the principal activity in this location.

Utility diversions

Gas – Work to realign the gas main near to Vauxhall Lane will continue.

Virgin media / Electricity / BT – Work to install the ducting and chambers to take the new cables will continue, with the main focus for activity other than the gas main being in the Longfield Road area of the scheme.

What is happening?

We are proposing to upgrade the existing single carriageway A21 between Tonbridge and Pembury to 2 lane carriageways.

The new dual carriageway will broadly follow the line of the existing A21 with a new grade separated junctions at Fairthorne (by the petrol station) and at Longfield Road, replacing the existing roundabout at the southern end of the scheme. At the northern end, there will be a minor change to the line of the slip road from the Vauxhall Lane roundabout where it joins the A21.

Parts of the existing A21 will be retained to provide access to houses, businesses, fields and woodland. A new bridleway for pedestrians, cyclists and horse riders will be provided along the whole length of the scheme. A new footbridge will be provided across the Pembury Bypass at Blackhurst Lane, replacing the existing crossing.

When and where is this happening?

The A21 links the Hastings/Bexhill and Tonbridge Wells/Tonbridge areas to the M25 and the trunk road network.

A draft Compulsory Purchase Order, Highways Act Orders and an Environmental Statement were published in December 2009 and a public inquiry was due to take place in July 2010. However, the public inquiry was postponed pending the outcome of the government’s October 2010 spending review. In the October 2010 spending review announcement the scheme was listed as one of those for which design and planning work would continue so that construction could start in the early years of the next spending review period (post 2015).

On 8 May 2012, the Roads Minister Mike Penning, announced that funding would be provided to develop the A21 Tonbridge to Pembury Dualling scheme, to ensure a "pipeline" of future Highways Agency major infrastructure improvements will be maintained, contributing to future economic growth, and supporting government's National Infrastructure Plan.

A public inquiry for the scheme was held between 14 May and 9 July 2013 and the Secretary of State's decision confirming that the scheme will go ahead was announced on 1 May 2014.

The decision letter and the Inspector's report of the public inquiry are on the Department for Transport’s website .

The contract to build the scheme was awarded to Balfour Beatty on 9 July 2014.

Some site clearance and advance environmental mitigation work started in September 2014 with the main construction work starting in spring 2015. Construction will take approximately 2 years.

Why is this happening and what will it cost?

Between the M25 and Tonbridge the A21 is a 2 lane carriageway standard with grade separated junctions, limited access and no central reserve gaps. Between Tonbridge and Pembury the standard drops to single carriageway with poor horizontal and vertical alignment and many individual accesses to properties, farm fields and woodlands. Approximately half way along the scheme there is a petrol station on the east side and junctions with two minor roads, Dislingbury Road and Pembury Walks, either side of the petrol station. This causes traffic congestion and delays on the A21, particularly due to right turning traffic. There are no footways and verges are either very narrow or non-existent.

This single carriageway section of the A21 experiences severe congestion throughout the day and particularly at peak times and has a poor accident record with an average accident rate (expressed as accidents per million vehicle kilometres) about 20% higher than the default value for a road of this type.

Between Tonbridge and Pembury the A21 passes through a very environmentally sensitive area with landscape, cultural heritage, ecological and settlement issues being key constraints to route improvements. Almost the entire route is within the High Weald Area of Outstanding Natural Beauty (AONB) and being an historic route, largely follows the landform. Further details of the environmental impacts of the scheme and proposed mitigation measures are on the environment page of this website.

The estimated cost of the scheme is in the range between £59.0m and £78.6m with a most likely cost of £69.7m.

How will the scheme be carried out?

Several options were considered before the "Preferred Route" was announced in 2003 which protected the line of the proposed scheme for planning purposes. The proposed scheme broadly follows the line of the existing A21.

At the northern end, there would be a minor change to the line of the slip road from the Vauxhall Lane roundabout. A new two level junction, called a "grade separated" junction, will be provided at Fairthorne roughly half way along the scheme. At the southern end the existing roundabout at separated junction. A new footbridge will be provided across the Pembury Bypass at Blackhurst Lane.

Parts of the existing A21 will be retained to provide access to houses, businesses, fields and woodland. A new bridleway for pedestrians, cyclists and horse riders will be provided along the whole length of the scheme.

To help us understand the impacts on the environment for these improvements, we have undertaken an environmental impact assessment of the proposals - this is recorded in an Environmental Statement (ES) and a Non Technical Summary (NTS) leaflet of the ES. The full environmental statement, explanatory statement and non technical summary leaflet can be viewed on the Publications section of this scheme's website. An updated and revised ES will be published before the public inquiry.

What are the benefits?

The main objectives of the scheme are to:

  • relieve congestion
  • improve safety for all road users
  • improve journey time reliability

The environmental objectives of the scheme are to:

  • mitigate the impact of the scheme on the AONB
  • minimise the adverse impact on the RSPB reserve and the Scheduled Ancient Monument
  • minimise the impact on ancient woodland

How do I find out more information ?

More information will be posted on this project page as it becomes available. You can subscribe to be alerted when updates are made.

If you have any queries about this project you should contact the Highways Agency Information Line by emailing ha_​info@​highways.​gsi.​gov.​uk or calling 0300 123 5000.

Details of scheduled roadworks are provided to help you plan your journey. Please note that works are weather- and resource- dependent and may need to be cancelled at short notice. This information is not updated in real time so please check Traffic England for current traffic conditions. Diversion timings are approximate and act as a guide only.

Will there be roadworks?

For night time lane closures, traffic lights will continue to be used during week nights throughout November.

A 40mph speed limit and metal safety barrier has been put in place throughout the works area to protect the road user and workforce.

Half Moon Lane and Pembury Walks were closed on 20/21 September 2015 due to continual disregard of the no right turn requirement. These will remain closed for a minimum of 6 months. Closure had agreement of Police and Kent County Council. Liaison with local residents on Half Moon Lane resulted in the access/egress at the junction with the A21 being changed to local access only with full closure further away from the A21.

Road Works

DateDurationDetailsAllow an Extra
Tuesday 24 November to Friday 27 November 2015Overnight 20:00 - 06:00A21 northbound closed overnight from A228/A264 Pembury junction to Vauxhall Lane exit Tonbridge.30 minutes diversion route in place.
Overnight Friday 27 November, Monday 30 November, Tuesday 1 December 201521:00 - 05:00Half Moon Lane closed from the A21. Restrictions removed from other end.10 minutes
Overnight Monday 30 November, Tuesday 1 December, Wednesday 2 December, Thursday 3 December and Friday 4 December20:00 - 06:00A21 Northbound closed between the A228/A264 Pembury Junction and Vauxhall Lane Tonbridge. Diversion in Place.30 minutes
Overnight Monday 30 November, Tuesday 1 December, Wednesday 2 December, Thursday 3 December and Friday 4 December 201520:00 -06:00Longfield Road closed heading towards the A21 from Knights Park. Longfield Road open heading from the A21 into Knights park.20 Minutes

How will you manage traffic?

At the Vauxhall Lane / A26 section of the A21, traffic will be separated prior to the southbound slip road into 2 dedicated lanes. Lane one will be used for traffic wishing to enter the A26 and the A2014. Lane 2 will be used for through traffic wishing to remain on the A21.

Will there be diversions?

A number of nights of full closures will still be required. Closures will be in place from A26 Quarry Hill junction Tonbridge through to the A228/A264 junction and will be effective from 8pm to 6am. A fully signed diversion route will be in place.

During most of the construction work, unless there is an emergency situation, there will be no need for the road to be closed during the day. Occasional further night closures may be required and these we will update here when they are confirmed.

A21 northbound closure times & actual closure points

  • Longfield Road roundabout to A26 Quarry Hill junction, 20:00 to 06:00 each night
  • A264/A228 junction with the A21 to Longfield Road, 22:00 to 06:00 each night

Access to North Farm - this is not a formal diversion route, so will not be signed, but is a suggested alternative.

  • Access straight over the roundabout from Tonbridge Road to Longfield Road will be possible during these closures. Vehicles needing access to the business park areas after 10pm should leave the A21 at the closure point (A264/A228 junction), turn left at the traffic lights onto Tonbridge Road, go past the hospital and then across the A21 roundabout onto Longfield Road.

A21 Southbound Closure times & actual closure points

  • A26 London Road / Quarry Hill junction to Longfield Road roundabout, 8pm to 6am daily.

Access to North Farm:

  • via main diversion route below until just before the A228 joins the A21, then see suggested route above

Formal diversion

When heading northbound the route will be to leave the A21 at the A264 / A228 junction; take the A228 towards West Peckham; turn onto the A26 through Hadlow, following the diversion route along the Tonbridge by pass, back to the A26 then re-join the A21. The southbound route will be in reverse.

Diversion route map

The scheme passes through a very sensitive area in environmental terms with landscape, cultural heritage, ecological and property issues being key constraints to route improvements. The scheme is almost entirely within the High Weald Area of Outstanding Natural Beauty ("AONB"). There is a scheduled Ancient Monument (Castle Hill Fort) close to the northern end of the scheme and an RSPB reserve at the south eastern end of the scheme. There are a number of ancient woodland sites to the existing A21.

We have surveyed the local area to assess the effect the scheme will have on the landscape and on plant and animal life. The results of the surveys and the measures we propose for reducing the effect of the scheme are contained in the envrionmental statement and are summarised in the non technical summary of the environmental statement. The link to these documents can be found on the ‘publications’ tab.

During construction we will use best practice to safeguard the local environment and will plan the construction works to minimise adverse effects on the local community and the environment.

Ancient Woodland

The scheme entails the unavoidable loss of 9Ha of ancient woodland for which 18Ha of translocated and planted woodland will be provided in mitigation. These areas will be managed for 25 years. In addition, 27Ha of existing woodland will be managed for 10 years while the new planting becomes established.


Local Communities and Land Use

Parts of the existing A21 will be retained to provide access to houses, businesses, fields and woodland. Earthmounds and planting will be used to screen the A21 from properties, with noise fences included where they will be effective.

The scheme will require additional land, most of which is good quality arable farmland or woodland. Four houses and 1 barn will need to be demolished to build the scheme.

A new route for pedestrians, cyclists and horse riders will be provided along the length of the scheme, and an additional pedestrian and cycle bridge provided at Blackhurst Lane to facilitate access to Pembury Hospital.


Noise and Vibration

Noise fences and earth mounds with planting will be provided to ensure that all residences currently close to the line of the existing A21 experience a reduction in noise level. Other areas further away from the A21 may experience a negligible increase in noise levels.


Air Quality

The majority of affected residential properties may experience improved local air quality as a result of the scheme proposals and because of the reduced traffic congestion. Air pollutant concentrations at properties near to the road will not exceed the levels that are set to protect human health.



Substantial areas of trees, shrubs and grassland will be planted, with the intention of fitting into the existing pattern of hedgerows, woodlands and pasture fields. Native species that are local to the area will be used where possible. The new junctions and road bridges will initially be intrusive features of the scheme but over time the extensive planting will create effective screening.


Wildlife and Nature Conservation

The Tonbridge to Pembury section of the A21 comprises a variety of habitats including woodland, hedgerows, grassland, streams and ponds.

Protected species found during our surveys include bats, dormice, badgers, breeding birds, great crested newts and reptiles. Although areas of woodland will be lost to the scheme, a wide variety of mitigation measures have been included to limit or compensate these impacts. The project team has consulted with statutory bodies to ensure that with mitigation the long-term effects on most species will be neutral, and the character of the landscape preserved.



The existing water environment will be protected by using drainage balancing and treatment ponds and facilities to contain pollutants. These measures will improve the quality of the water draining from the road system and ensure that there will be no increased risk of flooding in the area.


Historic Environment

The scheme runs through the High Weald an area inhabited by man for at least 6000 years. There is evidence of Iron Age, Roman and Medieval activity in the wider landscape. The High Weald landscape is formed of small fields and woodlands dating from Medieval and Saxon periods and the scheme has been designed to retain this historic form of the landscape.

So that the scheme has no effect on the Castle Hill Iron Age hillfort it will be necessary to demolish a Grade II listed farmhouse and barn. As a condition of the planning consent we will photograph and record the buildings before demolition and the barn will be carefully taken down and re-erected at a historic buildings museum.

The farmhouse itself is not unique and has been altered a lot during its lifetime, so does not warrant re-erection.

Environment Update

Work Undertaken In October

Archaeology & Cultural Heritage

The archaeological watching brief, where the archaeologists watch all new ground breaking activities, continued during October and the initial excavation at Castle Hill brick works was completed. Findings from this work are being reviewed and some additional work may be undertaken in November.

Ecology & Tree Clearance

Ecology surveys in advance of tree clearance were undertaken in the month. This is in preparation for the final section of translocation to be carried out. All required tree clearance is now complete.

Work to be undertaken in November

Environmental & Archaeology

The archaeologist will continue to provide a watching brief during the month.

The final woodland translocation (movement of ancient soils) will commence in November.

Business Case

A21 Tonbridge to Pembury - Business Case
Business Case - Information correct as at December 2010


A21 Tonbridge to Pembury Dualling Public Exhibition Information
A21 Tonbridge to Pembury Dualling Public Exhibition Information


A21 Tonbridge to Pembury Dualling - Full Statement of Case in respect of the applications for demolition of listed buildings
The Highways Agency's Full Statement of Case in respect of the applications for demolition of listed buildings issued under Rule 6 of the Town and Country Planning (Inquiries Procedure) (England) Rules 2000.
A21 Tonbridge to Pembury Dualling - Full Statement of Case in respect of the draft Orders
The Highways Agency's Full Statement of Case in respect of the draft Orders under the Highways Act 1980 issued under Rule 6 of the Highways (Inquiries Procedure) Rules 1994 and Rule 7 of the Compulsory Purchase (Inquiries Procedure) Rules 2007.
A21 Tonbridge to Pembury Dualling - Public Inquiry Notice
Public Inquiry Notice for the A21 Tonbridge to Pembury Dualling scheme.
A21 Tonbridge to Pembury Dualling - Pre Inquiry Meeting
A21 Tonbridge to Pembury Dualling Pre Inquiry Meeting Notice - 1 March 2013
A21 Tonbridge to Pembury Dualling - Outline Statement of Case February 2013
Outline Statement of Case in respect of Application for the Demolition of Listed Buildings - February 2013
A21 Tonbridge to Pembury Dualling - Notice February 2013
A21 Tonbridge to Pembury Dualling Department for Transport Highways Act 1980 - Notice February 2013
A21 Tonbridge to Pembury Dualling - Compulsory Purchase Notice February 2013
A21 Tonbridge to Pembury Dualling Compulsory Purchase of Land and Rights between Tonbridge and Pembury in Kent - Notice February 2013
A21 Tonbridge to Pembury - Outline Statement of Case
A21 Tonbridge to Pembury - Outline Statement of Case - January 2013


A21 Tonbridge to Pembury Dualling - Newsletter 1
This document is available on The National Archive website:   


A21 Tonbridge to Pembury Dualling - Revised Environmental Statement
Revised Environmental Statement, Non-Technical Summary of the Environmental Statement and Statement Explaining the Proposals
A21 Tonbridge to Pembury Statement of Case - May 2010
Full Statement of Case, Statement of Case - Listed Buildings, Statement of Case - Listed Buildings Appendix A

These videos shows a computer generated model of the A21 Scheme.

They illustrate how the scheme will look 15 years after opening, with trees between 5-7m in height and realistic traffic volumes.

The video sequence contains the following sections:

movements at the new junctions (Fairthorne Junction and Longfield Road Junction)

Fly-through of the scheme in a southbound direction

Drive-through in both northbound and southbound directions

Please note that these videos are hosted on the Highways England YouTube channel. If you are not able to access videos on YouTube you will be unable to view them.