Case Study

Warren Farm Sustainable Urban Extension – Chelmsford City Council

Purpose of the project:

The purpose of this project is to obtain an outline planning permission for a residential-led mixed-use development at Warren Farm, which is located on the western edge of Chelmsford.

The proposed development consists of up to 880 new homes, primary school with co-located early years and childcare nursery, travelling showpeople site, sports facilities including a pavilion/community centre, and neighbourhood centre (including retail, community, office and residential uses).

The site, which was brought forward by Crest Nicholson, was promoted through the ‘call for sites’ and emerging review of the Chelmsford Local Plan. The site was subsequently allocated as an urban extension to the City. The site now forms a major allocation in the adopted Chelmsford Local Plan (2020) in order to address identified local housing, employment and education needs.

Andrew Martin – Planning (AM-P) coordinated the EIA process, while another consultant prepared and submitted of the planning application package.

Description of the project:

AM-P was appointed as Environmental Impact Assessment (EIA) co-ordinator on this project.  As part of this role, AM-P led, managed and co-ordinated the preparation of an Environmental Statement (ES) which accompanied the outline planning application. AM-P also contributed to the ES, by assessing the socio-economic effects of the proposed development.

An indicative construction period of 10 years is estimated for the Proposed Development. An indicative start date of October 2022 has been estimated, with full completion by 2032.

The form of development has been informed through an iterative design process including the preparation of a Masterplan document. AM-P worked in collaboration with the Council, stakeholders and public to agree an indicative layout through the Masterplanning process.  The Masterplan was formally adopted by the Council. The Masterplan has informed and is reflected in the proposed Parameter Plans.

Key Issue:

The development of the Masterplan, planning application and compilation of the ES was undertaken during the pandemic. Inevitably, given this context, the process experienced a number of delays, with the Council unable to progress matters and the client ‘pausing’ work until clear timelines had been established towards submission.

Early iterations of the Masterplan included proposals for a bus link to be provided. In order to respond to this, initial proposals in the planning application sought to include this. Accordingly, early iterations of the ES assessed the significant effects of proposals which included this bus link. However, as the Masterplan process progressed (delayed due to the pandemic), it was clear that residents were against this bus link. Given this, it was decided that the bus link should be removed from proposals and replaced by a package of other sustainable travel options. This change came at a late stage in the development of the planning application and compilation of the ES.

The key issues were therefore twofold, in the difficulty of coordinating an ES in the context of the current pandemic and in ensuring that the ES robustly assessed the significant effects of late changes to proposals.

Lessons Learnt:

EIA Scoping

It is important to build in flexibility to the EIA process to ensure that the ES can respond sufficiently to potential changes that may occur during the development of a planning application. For example, the EIA scoping sought to assess proposals for up to 900 new homes. The final proposals were for 880 new homes. It enabled the Scoping Opinion to consider a worst-case scenario in respect of the maximum quantum of development that could come forward. The flexibility provided ensured that the ES could respond to changes (e.g. changing unit numbers and removal of the bus link) made to the final planning application making the process more responsive and robust.


Communication was vitally important during the process. This was doubly important given that a different consultant prepared the final planning application, while AM-P prepared the ES. Any changes to proposals had to be communicated in a timely and clear way. These changes then had to be communicated to the relevant consultants contributing to the ES to ensure that any significant effects that may arise due to these changes were sufficiently assessed. AM-P built a strong relationship with the consultant preparing the planning application and undertook regular update meetings to ensure clear and timely communication.

Limit Late Changes To Development Parameters

It is important to limit late changes to the development parameters. At a late stage in the process, the ES is virtually complete having assessed the significant effects of an earlier form of development. Late changes are not ideal as they need to be reviewed to assess if they result in any additional significant effects. While it is appreciated that EIA is an iterative process, late changes have the potential to delay completion of the ES and result in additional costs to the client to ensure all effects have been sufficiently assessed. Ideally, development parameters should be ‘fixed’ early in the EIA process to avoid late changes and generally should be as broadly defined as possible to allow flexibility in detailed design. Too much information on parameter plans can act as a difficult constraint to overcome in detailed design and inhibit innovation and high quality placemaking.


The measures described above helped AM-P to secure a positive outcome on this project, with ES being completed in a timely manner earlier this year.  The application has now been submitted to the Council and will be determined later next year.

Contact Details:

Mr Ian Butcher BSc (Hons) MSc MRTPI
Associate Director