Cambourne to Cambridge: about

There are plans for thousands of extra homes and employment opportunities, including:

• Cambourne West – 2350 houses,
• Bourn Airfield – 3500 houses and
• West Cambridge site – 383,300 square metres for employment

They would create heavy traffic along the A1303, causing growing pollution, delays and tailbacks at peak times.

The Cambourne to Cambridge busway would offer sustainable alternatives to driving for existing and new communities. It would help address the traffic congestion between Cambourne and Cambridge.

We are faced by an ever-growing climate emergency. It is vital we take action now to:

• cut congestion,
• improve air quality and
• provide better bus journeys.

The busway will serve our existing and growing communities and help people who travel along the busy A428/A1303 every day for work, school and leisure.

The dedicated bus route will create reliable public transport links. These will allow for reliable and regular ‘turn up and go’ services.

Initially, we expect up to eight buses per hour (each way) with direct express services to key employment centres. These include:

• Cambourne to Cambridge city centre, the station and Biomedical Campus at 10-minute interval (six buses per hour)
• Cambourne to Cambridge Biomedical Campus via M11 at 30-minute intervals (two buses per hour)

As with the existing St Ives Busway, the exact frequency and routes through the city centre would be decided by the bus operators. Bus operators would be able to increase the number of buses, if demand requires, as the route has capacity for more.

Yes, as soon as the technology is available to run over required distances and periods. We are currently expanding the city’s electric bus fleet and expect many more buses in operation by the time the bus route opens.

Should this not be the case on opening, as an interim measure, buses using the route will be required to operate to the highest emissions standards. This is currently Euro VI.

All buses would continue via Grange Road to destinations including the city centre, station and biomedical campus. The exact routes through the city would be decided by the bus operators, but are likely to follow the route of the existing U service.

The proposed route includes a West Cambridge campus stop, serving colleges, sports facilities and more.

There has never been any intention that buses would terminate at Grange Road.

We welcome plans for East West Rail (EWR) and improvements to the A428. Both bring more certainty for those travelling west of Cambridge. In comparison with Cambourne to Cambridge, they would serve broader objectives and more communities further afield.

Plans for Cambourne to Cambridge aim specifically to tackle congestion along the A1303. The busway serves the growing and new communities to the west of Cambridge (West Cambourne, Bourn Airfield and West Cambridge sites). These will not be linked by EWR. 

The A428 Black Cat to Caxton Gibbet improvements aim to resolve highway capacity issues west of Cambourne. They don't address poor connectivity and growing congestion between Cambourne and Cambridge.

The government has now published the route for EWR between Cambourne and Cambridge. The proposals include a new railway station at Cambourne and links to the new Cambridge South station.

Cambourne to Cambridge and EWR would complement each other:

• Cambourne to Cambridge would enter Cambridge from the west,
• EWR would link to Cambridge South, the Biomedical Campus and Cambridge station.

Our team can now begin work with EWR to incorporate a travel hub at the Cambourne Station. This travel hub would allow people to easily switch between rail, bus and active travel. It would therefore give greater opportunity for travel to work, education, healthcare and leisure.

The Cambourne to Cambridge scheme has gone through an extensive process of consultation and assessment of alternatives to arrive at a preferred option. The route reflects various demands and constraints. It needs to:

• connect certain destination and stopping points,
• have a relatively straight route between them to ensure the best journey times,
• be a segregated route as much as possible so that buses do not get stuck in existing traffic,
• serve the West Cambridge campus and
• cross the M11 which, in practical terms, needs to happen south of Junction 13 (where the slip-roads diverge) if a route south of the A1303 is selected.

At the same time, the route maintains an alignment which

• takes account of the existing uses of land, including environmental considerations,
• avoids houses on Cambridge Road and
• holds to an agreement with local residents that proposed bus services should run no closer to homes than existing bus services.

We recognise the environmental impacts of an alignment through the orchard and we are instigating numerous measures to limit and mitigate these. But there are no reasonable alternatives that don’t have their own environmental impacts or transport limitations.

We recognise the importance of Coton Orchard to wildlife. Its ecological characteristics stem more from the wider habitat types to which the trees contribute, than from the number of trees themselves. The habitats within the orchard have been thoroughly surveyed and assessed using appropriate guidance. Much of the orchard comprises grassland of low ecological interest and the apple trees are a component part of this. In the east of the site, trees form part of the dense scrub habitat.

We are committed to mitigating, as far as possible, adverse ecological impacts of our scheme generally, and specifically in the orchard. This will include new habitats within the scheme on what is currently intensively farmed land, such as new:

• hedges,
• tress and
• grassland areas.

We will also create new habitats away from the scheme to compensate the habitat loss in the orchard and elsewhere, and to create an overall increase in biodiversity by up to 20%. The approach to this biodiversity net gain (BNG) follows one developed by Natural England and will soon be adopted on all new developments in the UK. We have identified potential areas where this habitat offset and BNG will be sought and will pursue these with landowners over coming months.

At the orchard, approximately 500 trees are in the area in which we are looking to build and operate the busway. If the scheme receives approval, they will likely need to be removed. Most of these are apple trees planted some time after the orchard was created. They are on dwarf rootstock to make fruit picking easier and therefore do not contribute to what is referred to as ‘traditional orchard’ habitat. Of the 11 remaining trees from the original orchard, up to six are located within the scheme footprint, though we plan to preserve as many of these as possible. The total tree loss would depend on the final construction plans.

It is important to recognise how the orchard has declined since its creation in 1922 from around 24ha to around 9ha today. Parts have been given over to the garden centre and car parks, while other areas have been left to regenerate. The Cambourne to Cambridge proposals would impact on less than 20% of the remaining active orchard. Less than half a hectare qualifies as ‘traditional orchard’ and ‘habitat of principal importance’ as defined by the Joint Nature Conservation Committee.

Mitigation proposals are being developed to:

• preserve views,
• screen infrastructure and
• limit the impact on the landscape.

The total tree loss would depend on the final construction plans. But we are committed to planting 1,500 new trees along the route, significantly more than we will remove.

Hedgerows will also largely be maintained.

We are committing to deliver a minimum 10% biodiversity net gain for the scheme overall, with the ambition of achieving 20%.

Approximately 500 trees would be removed from Coton Orchard. The majority of these are relatively young on dwarf rootstock and between 2 and 6 of the older trees. The total area of the remaining active orchard measures 9.02ha; of this 1.52ha will be lost to the scheme. This would leave roughly 80% of the remaining active orchard untouched and unaffected by development.

The GCP has drafted a planning condition which will form part of a wider planning commitment with the Greater Cambridge Shared Planning Service. We will be bringing this to the attention of the Planning Inspector and expect it to be a firm obligation placed upon us as part of the TWAO process.

In terms of delivery, this will be an obligation included within the terms and conditions of the contract to deliver the Cambourne to Cambridge works. There will be a warranty period. During this, the contractor will be required to replace any failed trees and/or maintain an agreed plant density. This period is still to be determined but likely to be of the order of five years.

The A14 provides lessons to inform future planting. We have already requested feedback from National Highways.

Many of the A14 trees were planted in isolated locations on new earthworks. Most of the Cambourne to Cambridge trees will be planted in locations where watering and other maintenance is relatively straight forward.

We would also seek better viability of planted trees; for example through mulching.

Ultimately, the planning commitment is answerable to elected members. They have oversight and can require any remedial works to be enacted.

It is 8.7 miles (14km).

The scheme is currently proposed to cost £160m.

Our proposed scheme would be a mainly off-road, segregated busway with a service track providing an active travel path, as well as a new travel hub. The do-minimum option would have been along the existing A428 and A1303.

A number of on-road options, including proposals from local stakeholders, were assessed in detail as part of the process required by the Department for Transport and could not provide end-to-end bus lanes, even in-bound only, due to constraints such as the Madingley Wood Site of Special Scientific Interest and the American Cemetery.

Yes, we considered different route options including:

• bus lanes along the existing roads,
• junction improvements along the A1303,
• routes north of the A428/A1303 and
• routes south of the A428/A1303.

All route options have been through a rigorous assessment process, which is explained here in more detail. Background documents on these options and their assessments are linked throughout the text.

Option assessments

We fully assessed alternative options as part of preparing the Outline Business Case for the scheme. These assessments conform with Department for Transport (DfT) Transport Analysis Guidance (TAG). A number of on-road options were assessed in detail but did not perform as well as the proposed scheme.

We considered both on and off-road routes as part of the option development. These options were compared in the Phase 1 Consultation undertaken in 2017/18.

As the scheme was developed towards the Outline Business Case stage, options were refined to an off-road option south of the existing A428/A1303. These options were substantially amended to reflect issues emerging from consultation. They now form the basis for the current preferred option.

Low-cost, on-road option

A low-cost alternative was also developed, as required by DfT guidance. This was based on on-road improvements and included:

• minimal infrastructure changes west of Madingley Mulch roundabout and
• sections of inbound bus lane between Madingley Mulch Roundabout and Lady Margaret Road to the east of the M11. Due to the constraints at the M11 Junction 13, the bus lane was not continuous and terminated before the bridge. Buses would join general traffic over the bridge, before re-joining a bus lane on the other side.

Option appraisal reports

Following the 2017/18 consultation, the Option Appraisal Report 1 was created, as part of the Outline Business Case. It recommended the best on-road and off-road alternative to be taken forward for further consideration. These alternatives were based on the schemes taken to consultation.

The on-road and off-road options were then assessed further in Option Appraisal Report 2. It concluded that an off-road option for Phase 1 was better performing.

The GCP Executive Board noted in December 2018 that the proposed off-road option best meets the strategic and policy objectives of the Greater Cambridge Partnership.

Independent audit

An Independent Audit was undertaken in 2021. It confirmed there has been proper consideration of alternative options. These include various alternatives and iterations put forward by stakeholders throughout the life of the scheme since 2014.

The independent review acknowledges:

• a robust appraisal process and
• that ‘the process has included extensive consultations with stakeholders and affected parties.
• The preferred option has taken these views into account and
• proposed mitigation measures where negative impacts are identified.’

See more on the independent audit here.

Other options

Alternative stakeholder options have also been extensively considered and discussed to further evidence full consideration of options.

Cambourne to Cambridge Local Liaison Forum group: significant correspondence and evidence of meetings about alternatives proposed by the group has been published online - Cambourne to Cambridge: LLF (greatercambridge.org.uk).

Northern alignments and on-road quick wins: evidence of previous assessment of northern alignments and on-road “quick wins” was presented in two Technical notes published in 2019 - Cambourne to Cambridge: background (greatercambridge.org.uk). These notes highlight limitations in effective and deliverable short-term solutions. This is due to:

• building congestion on the highway,
• the impacts of significant disruption from any works and required boundary land-take, leading to likely objection,
• protracted process and
• longer delivery times.

The planning process has advanced, having discounted workable and viable alternatives to progress with modelling, further assessment and ultimately present the proposed scheme as set out in March 2023, in line with DfT guidance and process. Full assessment detail is reported in the Outline Business Case.

The Cambridge Past, Present and Future (CPPF) 2021 proposal

The CPPF 2021 proposal was submitted to the Independent Audit in March 2021.

The CPPF option comprises some modest sections of inbound bus lanes and junction improvements. It does not provide a Cambourne to Cambridge scheme.

The project team carried out a high-level review of the CPPF report at the time.  The report’s author stated that the report proposed a “package of quick-win interventions to the Greater Cambridge Partnership and Combined Authority as an effective and low-cost interim solution whilst details of longer-term infrastructure schemes, such as East West Rail, the CAM network and the Girton Interchange, are worked out”. The alignment of East West Rail (EWR) is to be confirmed but would not directly serve the growing Bourn Airfield community and West Cambridge site. The CAM network has been cancelled and Girton Interchange upgrade has never been proposed by National Highways. Had the CAM been delivered, as the CPPF report assumed, then it would have provided a fully segregated off-line route for the Cambourne to Cambridge corridor. As such, a quick win package was never intended to, and therefore cannot, assure the future growth of the Cambourne to Cambridge corridor.  The delivery of Cambourne West, Bourn Airfield and West Cambridge developments cannot be achieved with this short-term package of proposals predicated on the assumption that an off-road route for Cambourne to Cambridge (whether or not the GCP proposal) was to be provided. This position was supported by the Independent Audit which concluded that a short-term alternative “does not invalidate the assumptions and constraints for the preferred option as a long-term solution to meet the growth in travel demand along the corridor”.

Cambourne to Cambridge has been developed over many years following Department for Transport processes. We consulted four times, including as part of the development of the Environmental Impact Assessment.

We have also carried out rigorous assessments of off and on-road route options. This included routes along the A1303 as proposed by stakeholders. The business case and documents published on our website show these assessments.

The route has also been subject to an independent audit, which found the GCP’s process to be robust.

The Cambridgeshire & Peterborough Combined Authority under the previous mayor reviewed the route twice (Arup's review, Jacobs' review). They concluded that the preferred alignment was correct.

The need to preserve the American Cemetery and important sites along the A1303 – including Madingley Woods, a Site of Special Scientific Interest – influenced the decision for the off-road route.

Four consultations have been held since 2015, including an Environmental Impact Assessment. More information on these consultations is available in the full consultation report, Appendix 12 on the Latest - Transport & Works Act Order page.

Response details for each consultation are on the scheme's background page.