Heritage Impact Assessments
Sweco’s Historic Environment and Archaeology team have a wealth of experience working on various projects including residential development, mixed-use development, infrastructure and renewables. Our specialists can therefore carry out fully integrated Heritage Impact Assessments (HIAs) to the highest professional and ethical standards in line with the standard and guidance set out by the Chartered Institute for Archaeologists (CIfA).
What is a Heritage Impact Assessment?
A Heritage Impact Assessment – usually part of a wider heritage consultancy project – is a document that is submitted in support of a planning application which sets out the impact(s) a development could have on specific heritage assets, like archaeological remains and historic buildings. HIAs can also be called Heritage Statements, but the content and outcome of both documents is the same.
One of the main benefits of an HIA is that it is specifically focused on impacts to a single heritage asset, or a small number of heritage assets. It is carried out when all the design details are known and fixed so there is as much certainty as possible.
Why do I need a HIA?
An HIA may be required if there are already known heritage assets on a site or in the surrounding area which have been identified as sensitive to the development proposed.
Understanding the impact a development can have on heritage assets within the Historic Environment is an important component in the planning process.
These can be complex issues which need careful analysis by a suitably qualified professional who understands how significance is defined in national and local planning policy, how a development could affect that significance and to what degree impacts could be mitigated or offset.
What should be included in a Heritage Impact Assessment?
This depends on the development and what heritage assets might be affected. In most cases, the design work for the development has been completed and fixed so it is possible to be detailed on how much of an archaeological feature may be damaged by foundations or how much of a wall of a historic building will need to be removed, for example.
The HIA will set out those impacts and how that will affect the significance of the heritage assets allowing the eventual decision-makers to balance those impacts against the benefits of the overall scheme.
A HIA can include both an assessment of impacts from physical changes as well as from changes in the setting of a heritage asset. Setting refers to the surroundings in which a heritage asset is experienced and can be a component of what makes it important.
HIA differs from a purely Desk-based Assessment which is usually produced to establish the nature, extent and significance of the historic environment within a site and the surrounding area.
What are the steps of a HIA?
An HIA is primarily a desk-based exercise but it is supported by a site visit to allow the heritage consultant to understand the asset in its context and identify any previously unknown elements or components which could be important in the assessment.
An HIA will normally use a wide range of sources including data on designated heritage assets from statutory bodies (Historic England, Historic Environment Scotland, Cadw, Department for Communities), data on non-designated heritage assets from the local Historic Environment Record (HER), historic maps, LiDAR data etc.
To ensure the HIA is appropriate and meets the requirements of the planning authority, the process will normally include communication and consultation with the relevant officers.
The HIA is a report with accompanying illustrations and photographs which can be sent directly to the responsible planning authority.