Transport Development Management (TDM)

Why and how we use TDM to ensure highway safety, convenience and amenity are not compromised

The role of Transport Development Management is primarily one of ensuring that highway safety, convenience and amenity are not compromised through developments. We do what we do because we believe unregulated development can lead to:

  • avoidable fatalities
  • environmental degradation
  • unhealthy urban networks where economic activity is not supported.

We believe in working collaboratively, especially with enlightened developers, to influence the approach and the details of this important aspect of development. Our customer is, therefore, everybody who uses the transport infrastructure in Oxfordshire. Manual for Streets encourages just such a collaborative approach. Our pre-application process is a way of ensuring this.

Our direct clients are usually the City and District Councils for whom we provide consultation responses, as well as overseeing County applications in the same impartial fashion.

The recommendations of these reports are interpreted through the democratic process with other considerations, when decisions are made on planning applications. We work to serve this process to optimise conditions for communities, from a transport point of view.

Our work contributes to the fulfilment of our Connecting Oxfordshire: Local Transport and Connectivity Plan (LTCP) and therefore serves Oxfordshire’s constituents.

Our vision is: Development proceeding smoothly in transport terms, recognising the historic nature of Oxford and Oxfordshire building a prosperous, sustainable, secure and safe future with the infrastructure necessary to cater for this.

How we do what we do

We are more than willing to provide input before planning applications are made. This is in the form of pre-application advice from a transport perspective.

The correct level of supporting documentation for an application will ideally be determined at this stage (Transport Assessments, Transport Statements, Travel Plans, Travel Plan Statements, Design & Access Statement).

Our Transport Development Management team is a statutory consultee of the planning process and therefore gives technical advice on the transport and highway implications of each proposal.  We are not the decision-making authority, this is the Planning Authority.

Our main medium of operation is the consultation response to the relevant Planning Authority, at the Districts and the County planners.

There are many aspects of a consultation response, which relate to this, including:

  • assess the transport and highway implications of new development within the framework of government and council guidelines and make recommendations to the Local Planning Authorities as to whether the application should be permitted or refused on transport grounds
  • protect the highway network and existing transport infrastructure from the impacts of new developments
  • secure the upgrading of existing and provision of new transport infrastructure to mitigate against the impact of the development proposals
  • secure contributions to improve transport provision in a wider context to account for the cumulative effects of new developments
  • promote our sustainability objectives by encouraging walking, cycling and public transport
  • consulting widely including taking into account the wishes of parishes and councillors

Impartial advice is given as a consideration of engineering matters. This often involves coordinating responses from many parts of our department. We do this by reference to the standards contained in a series of design guides:

Three basic responses are ultimately possible:

  • no objection
  • no objection, with conditions and/or mitigation and/or developer contributions
  • objection/holding objection

By the judicious use of conditions, outright objection is rarely necessary, unless proposals are totally unacceptable with ‘severe’ implications and / or are likely to be ‘unsustainable’.

The generation of traffic by a development is essentially a form of externality produced as a consequence of its existence. By the principle of polluter pays, developer contributions are required in order to deal with, such negative consequences, as can be mitigated for and additionally under some circumstances what gain can be made to invest in future-proofing development.

What is the context for what we do?

The Department for Communities and Local Government (DCLG) published its National Planning Policy Framework (NPPF) on 20 July 2021.

The NPPF replaces all Planning Policy Guidance (PPG) Notes and Planning Policy Statements (PPS) with a single document of just under 50 pages.

This is in line with the Government’s ‘Localism’ reforms, to reduce the role of central guidance and emphasise the local. This places the onus firmly on local authorities to provide the policy framework for sustainable development – in accordance with the twin priorities of economic growth and management of adverse environmental impact.

National Design Guidance to achieve the above with a ‘sense of place is contained in the two volume Manual for Streets (MfS).

Our local guidance stems from the aims of the Connecting Oxfordshire: Local Transport Plan (LTP4) covering the period 2015-2031.

There are various levels of supporting documentation for a planning application, which should be determined as to which is appropriate in the pre-application process, these include:

Releasing Development Strategy in Didcot and surrounding villages in the vicinity of HIF1 Schemes

Prior to Didcot Garden Town Centre Housing Infrastructure funding (HIF1) being secured in June 2019, it was established that the local and strategic highway network that serves Didcot and the surrounding area has severe congestion and capacity issues during the morning and evening commuter periods.  The areas of concern most affected have been identified as the river crossing between Sutton Courtney and Culham, Clifton Hampden village signal junction, and the A4130 as the main route between Didcot and Milton Interchange (A34).

To manage the highway network a strategy was devised in 2017 to control development within areas (including Didcot) that have the most severe capacity issues in the absence of strategic highway infrastructure to support new growth in the Vale of White Horse and South Oxfordshire districts (as identified in LTP4 and district Local Plans). This strategy involved TDC officers objecting to new developments (including single dwellings) that would generate a new vehicular trip in the morning and evening commuter peak times.

While this approach enabled both district councils and the County Council to manage the impact of new development on the highway network and support the HIF1 bid, it has placed the council’s position under scrutiny and frustration from developers who have been unable to progress their development sites since the HIF1 funding was secured.

Securing HIF1 funding and the adoption of the district councils Local Plans has provided more confidence in the delivery of HIF1.  Although it continues to be recognised by OCC that in the absence of the HIF1 infrastructure, much of the highway network is at design capacity during the morning and evening commute times. It remains the fact that all applications are assessed on their merits and TDC officers are mindful that there is an overall national planning gain in delivering houses and economic growth in Oxfordshire and should not be seen to be obstructing this, whilst also maintaining a working highway network. 

With that in mind and to assist with the delivery of much-needed housing in the Vale of White Horse and South Oxfordshire districts a strategy to release development was adopted by Oxfordshire County Council's Cabinet on 22 June 2021 to allow some development to come forward prior to the new HIF1 funded infrastructure being open for public use based on the following requirements:

  • Development site housing build programmes/trajectories/occupations being aligned with (or after) the delivery of HIF 1 which will require occupation thresholds/controls on development sites.
  • Development sites to provide agreed sustainable/active travel infrastructure at the beginning (early occupations) of development sites to reduce traffic impact on the highway network prior to HIF1 delivery.
  • New services or enhancements to existing bus service arrangements being implemented at the beginning (early occupations) of development sites.
  • Local off-site and on-site highway works to be delivered at the early stages of development to lessen the direct impact of a development site on the highway network.
  • Travel Plans prepared and approved by the council’s Travel Plan team with deliverable and monitored targets.
  • Strategic transport/highway contributions will be sought in accordance with Regulation 122 and the three Section 106 tests.

Due to the diverse nature of development that is promoted in the Vale of White Horse and South Oxfordshire districts a four-tiered approach is to be used:

Tier 1: Single house (and extension) proposals that will generate new vehicular movements in the morning and evening commuter peak hours are no longer to be objected to by TDC officers on traffic impact (HIF1) grounds.  This is on the basis HIF1 funding has been secured and OCC is confident in delivering HIF1.  Each Tier 1 planning application will be assessed on its merits.

Tier 2: Developments of less than 10 houses that will generate new vehicular movements in the morning and evening commuter peak periods are no longer to be objected to by TDC officers on traffic impact (HIF1) grounds. This is on the basis HIF1 funding has been secured and OCC is confident in delivering HIF1. Tier 2 development proposals will be assessed on their merits and strategic highway and public transport contributions will be sought as well as any appropriate mitigation works.

Tier 3: Development sites of 10+ houses that will generate new vehicular movements in the morning and evening commuter peak periods are no longer to be objected to by TDC officers on traffic impact (HIF1) grounds.  This is on the basis HIF1 funding has been secured and OCC is confident in delivering HIF1. Tier 3 development proposals will be assessed on their merits and strategic highway and public transport contributions will be sought.  Off-site and on-site highway infrastructure will be expected to be delivered early on for these development sites to encourage sustainable and active travel patterns.  Occupation controls will be applied to development sites to lessen the cumulative impact on the highway network.

Tier 4: Commercial developments.  It is recognised by OCC that there are significant existing and proposed commercial sites in the area that help support the local and national economy such as Culham Science Centre, Milton Park, Harwell Campus (and others).   While these sites are not directly linked to releasing housing via the delivery of HIF1 they are to play an essential role in its delivery, such as providing land or delivering some elements of the highway works.  While HIF1 funding has been secured and OCC is confident is delivering HIF1, Tier 4 development proposals will be assessed on their merits but will be expected to mitigate their own impact through local and site wide measures which may include providing excellent pedestrian, and/or cyclist provisions and enhanced frequent public transport service provisions to help reduce their impact in the local area before HIF1 is delivered and in the long term.  Restrictions on gross floor area usage or occupation thresholds may be applied to development sites to lessen the cumulative impact on the highway network.

While this tiered approach will enable some development to come forward prior to the delivery of HIF1;  County Council officers will continue to monitor the operation of the highway network in consultation with the Vale of White Horse and South Oxfordshire district councils and will review this tiered approach until the delivery of HIF1. 

For pre-application advice in relation to the tiered approach please use OCC’s chargeable pre-application advice please approach pre-application service or contact transport.development.control.majors@oxfordshire.gov.uk.

The full Cabinet report.

New public highways

Often as a result of a planning application getting consent, the highway either needs to be altered or new highway is constructed.  When this happens a S38 and/or S278 application for the relevant legal agreement is required. 

We have a set of standard details to assist with the design of the highway works.