Tom Rudd, town planner, and Duncan Mackay, associate town planner at BDP describe how they achieved sustainable development from outline to detailed design on a major mixed-use development.
Wood Wharf is a major mixed-use development within the pre-existing urban area of the Isle of Dogs. Canary Wharf Group’s latest scheme includes a maximum of 728,880 sq m of floor space, comprising approximately 3,600 new homes, 350,000 sq m of business space, 27,500 sq m of retail and 7,000 sq m of community uses.
Outline planning permission was granted in December 2014, consenting the development of a comprehensive masterplan over 12 years, subject to approval of multiple reserved matters applications. The outline permission is flexible as to the type and appearance of development, so that developers can respond to dynamic local and market needs while giving enough information to identify the likely significant environmental effects to inform the determination of the application. This flexibility, and the timescales involved, have presented significant challenges in ensuring all likely significant effects are assessed throughout the process.
Assessing environmental effects from outline to detailed design
The EIA regulations require environmental statements (ES) to include a description of the likely significant effects of the development on the environment. EIA practitioners must decide what information to assess at the outline and reserved matters stages to provide flexibility for future development, while providing an accurate assessment of likely environmental effects to minimise the need for unnecessary testing through the reserved matters applications.
The approach adopted for the Wood Wharf ES and ES addendums demonstrates a pragmatic solution to this question, which is consistent with an approach known as the Rochdale envelope, under which consents are conditional on providing the final details for agreement prior to construction.
However, with a 12-year delivery period for the scheme and many reserved matters applications required, the relationship between outline assessment and detailed design is potentially more complex than the typical outline ES.
Outline ES
As limited detailed design information was available, the outline ES primarily focused on an assessment of the following specified parameters and indicative scheme:
- parameter plans define the extent of the proposed routes, spaces and buildings across the site;
- the development specification sets out the type and quantity of development that could be provided across the site;
- design guidelines set out principles of design which future reserved matters applications are required to comply with; and
- indicative scheme represents a realistic manner in which the maximum floor area could be built out within the above specified parameters.
Many of the technical assessments within the EIA assessments tested the maximum extents of these parameters, as these generally constituted the worst case scenario.
A number of the technical chapters, such as socio-economic and sunlight and daylight, assessed the indicative scheme, where it was necessary to inform a robust assessment, or where it represented a worst-case scenario. It is important that each technical author defines in their methodology whether they have relied on the parameter plans, or any details from the indicative scheme.
This approach assessed all likely significant effects that could reasonably be expected to come forward through the reserved matters applications, without full design details.
Reserved matters
As the reserved matters applications are in line with the specified parameters and largely similar to the indicative scheme, the majority of the assessments contained within the outline ES remain comprehensive and robust, and therefore apply to subsequent stages in the planning process.
The reserved matters ES addendums review the detailed design in the context of the outline ES to assess whether the significance of any of the effects has altered, or whether new effects have arisen as a result of the following considerations:
- changes in the baseline conditions;
- consistency with the specified parameters and indicative scheme;
- effects that were not identified or identifiable at the outline stage;
- incorporation of mitigation identified at the outline stage; or
- any further relevant information.
The reserved matters ES addendums do not require all the assessments of effects to be retested, but rather for the detailed design to be considered in the context of the outline ES. Testing is only needed where the outline ES relied on an assessment of the indicative scheme.