You Ask, We Answer

We’re technical experts in the complex and ever-changing world of civil and structural engineering design and technical approval.

What are Departures from Standard?

Our answer is based on the Link team’s collective experience, which includes several years of working with National Highways and agreeing on departures where it is deemed necessary to do so.

It is important to note, applying for a Departure from Standard is a last resort and best endeavours should be made to avoid a departure by looking at all potential options. Excessive cost associated with these alternative options is not a sufficient answer to rule them out, although it is a considering factor. There should be no cost restriction to providing a safe design.

GG 101 – Introduction to the Design Manual for Roads and Bridges, highlights the definition of a Departure as ‘Variation of waiving of a requirement carried out in accordance with the Overseeing Organisation’s Procedures.’

Departures from standards in regard to highways refer to the instances where the design, construction or operational practices deviate from established guidelines, regulations or industry standards.

In order to understand if a departure from standard is required it is essential to understand the terminology used within clauses to determine if they must be adhered to. The following verbs can be seen throughout GG 101 and each one provides a different meaning.

  • ‘Must’ – indicates a statutory or legislative requirement.
  • ‘Shall’ – indicates a requirement of the overseeing organisation.
  • ‘Should’ – indicates advice expressed as a recommendation.
  • ‘May’ – indicates advice expressed as a permissible approach.

When applying for the approval of a departure from standard it is important to engage with the overseeing council/organisation to ensure the proposals are reasonable. In regards to National Highways, the DAS system must be used to review existing and apply for new departures.

This process will involve several stages and can be broken down into the below steps:

  1. Identify the need for a change in the proposed highway. A good example of this would be to increase the number of lanes on a slip road to deal with increased traffic volumes.
  2. Highlighting any existing departures from standards that may already be in place as this may impact / restrict the inclusion of a new one.
  3. Providing a detailed justification for the departure from standard. Clearly explaining the reasons for this and exploring several options to limit the need for this – cost is rarely a valid reason.
  4. Submitting the application to National Highways via the DAS (3.0) system. Good practise would be to of already had discussions with National Highways to ensure all of the above.

Departures from Standards can occur, and impact sites, in various ways. Therefore, understanding any implication is vital. The below highlights many factors to consider and understand when reviewing potential departures:

  • Location
  • Departure from Standard – which clause is being effected
  • Extent of Departure from Standard
  • Design Speed
  • Associated Departures
  • Alternative options considered
  • Benefits / adverse impacts / Risk
  • Cost implications
  • Environmental impact
  • Mitigation
  • Overall Justification.  

Understanding what constitutes a departure from standard is a very complicated process and varies between all of the standards whilst specifically linked to a design proposal.

It is the responsibility to of the overseeing organisation to review any proposed departures and to ensure that a high level of safety is maintained at all times.

If you are looking at a site which could potentially require a departure from standards and want to know more about the process, please contact us at and we would be more than happy to provide you with some site specific advice.

Jul 27, 2023