Dominic Watkins, from Chris Blandford Associates, highlights some lessons learned on environmental impact assessment (EIA) from the Durham riverside regeneration project
The Durham city centre masterplan identifies the Durham riverside as a priority area for regeneration.
The Durham riverside renewal project aims to create a new mixed-use development of offices, homes, shops and restaurants, which will regenerate an important part of Durham, as well as helping to safeguard and create more than 2,500 jobs.
A significant benefit of the project is the enhancement of public access to Durham’s riverside and its important historic landmarks and amenities.
The site
The redevelopment of the neglected, semi-derelict and prominent site of the city’s former ice rink at Freeman’s Reach forms the first phase of the project.
A planning application for the demolition of the former ice rink and the historic Bishop’s Mill, and the construction of an office development, and associated restaurant and cafes, information kiosk, a hydro-energy generating turbine (an Archimedes’ screw) and public realm works, was submitted in November 2012. Planning permission was granted by Durham County Council in March 2013.
The planning authority’s screening opinion determined that an EIA was necessary due to the site’s sensitive location within the setting of the Durham Castle and Cathedral world heritage site; its current appearance and usage; and the nature of the proposed use and scale of the development.
Scoping
An effective scoping process, undertaken in consultation with the planning authority and statutory consultees, was critical to ensuring that the EIA focused on assessing only significant effects. The primary issues were:
- the potential impacts of the development on the historic environment;
- landscape/townscape character and views;
- biodiversity; and
- hydrology and flood risk.
Other topics/effects that were unlikely to give rise to significant effects were scoped out of the EIA process.
In line with the EIA Directive, and relevant national legislation, the likely significant effects of the proposed development were predicted and impact significance evaluated using transparent criteria. Where significant adverse impacts were anticipated, the EIA identified mitigation measures to avoid, reduce and/or remedy the adverse effects.
The residual significant effects, positive and negative, which must be taken into account in the decision-making process, were then evaluated.
Alternatives
The consideration of alternatives was another important element of the EIA process. In addition to consideration of alternative sites as part of the flood risk assessment, the EIA also considered a range of alternative design solutions.
Throughout the design process, potentially significant adverse impacts were designed out wherever possible through a process of interaction between the EIA and design teams.
This involved, for example, consideration of alternative building layouts and forms, hydro-power options and public-realm design strategies informed by specialist technical studies and consultation with relevant consultees – such as English Heritage and the Environment Agency.
In this way, mitigation measures were embedded into the design of the proposed development from an early stage.
Historic townscape
One of the major challenges for the EIA process involved the assessment of impacts on Durham’s historic townscape.
The preparation of accurate visual representations from key viewpoints (agreed with the planning authority and English Heritage) was key to assessing direct impacts on the Durham city centre conservation area and indirect impacts on the nearby world heritage site.
The EIA demonstrated that the scale, massing and architectural quality of the proposed development would have a significant beneficial impact on the character and appearance of the conservation area without adversely impacting the world heritage site.
Significant positive impacts were also predicted by the proposals to enhance public appreciation of the site’s historic environment context through increased access and onsite interpretation.
The EIA was also key to demonstrating that the demolition of the former ice rink building and the Bishop’s Mill, a heritage asset of local significance, would be far outweighed by the overall and wide-ranging benefits of the development.
The EIA included mitigation measures agreed with the planning authority and statutory consultees to effectively monitor and manage significant adverse effects relating to archaeological, ecological and flood-risk impacts. The mitigation measures include:
- a programme of archaeological monitoring, investigation and recording;
- implementation of a construction environmental management plan;
- implementation of mitigation measures in accordance with the findings of the flood risk assessment (including a flood management plan)
- construction and post-construction monitoring of bats, otters, breeding birds and aquatic macro-invertebrates and fish; and
- provision of bat roosts and otter refuges to compensate for those lost through demolition of the derelict Bishop Mill building and associated structures.
The project’s EIA was successful in providing a robust evidence base for the planning authority, statutory consultees and those affected by the proposed development. It demonstrated that the proposals would have no permanent significant adverse impacts on the site’s prominent and sensitive location within the historic city of Durham.
This article was written as a contribution to the EIA Quality Mark’s commitment to improving EIA practice.
Dominic Watkins is a director at Chris Blandford Associates
