Improving ecological input to Construction Environmental Management Plans (CEMPs): Delivering Better Outcomes for Nature

Improving ecological input to Construction Environmental Management Plans (CEMPs): Delivering Better Outcomes for Nature

Ecological mitigation identified in Construction Environmental Management Plans (CEMPs) is often presented in a way that makes it inaccessible to Construction Managers. This reduces the chances of effective implementation, leading to poorer outcomes for nature and undermining the impact assessment process.

In this article BSG Ecology Principal Consultant Tom Flynn explores how ecologists can translate the structure and terminology of an ecological impact assessment into more accessible text that will result in practical, deliverable CEMPs.


The purpose of a CEMP is to set out construction-stage environmental mitigation in sufficient detail to allow it to be incorporated into the construction programme and to be implemented on the ground. A CEMP will often be required by a planning condition, or may simply be produced to ensure that all mitigation committed to will be delivered and the risk of legal infringement reduced.

Ecologists input to both broadly environmental CEMPs (covering disciplines such as air quality, noise and hydrology) and ecology-led CEMPs. The latter, sometimes referred to as Construction Ecological Management Plans, or CEMP-Bs (with the B referring to biodiversity), are typically produced for large and complex projects that require substantial input from an ecological clerk of works (ECoW).


Guidance on the scope, structure and content of ecological input to CEMPs is provided in Section 10 of British Standard BS42020 Biodiversity – Code of practice for planning and development (BSI, 2013). BS42020 also notes the need for proportionality of detail, taking into account the scale of development and the potential risks to biodiversity.

There are some practical issues with the guidance provided in BS42020, however. In particular it has the potential to direct the writer away from producing simple self-contained method statements that a Construction Manager without an ecological background is likely to find straightforward to interpret. In this context, it should be noted that only the largest and most complex developments will typically have an ecologist involved with the construction team.

Improving Accessibility

A well-written CEMP should translate the aspirations of an Ecological Impact Assessment (EcIA) into clear, non-technical, task-specific actions the Construction Manager and wider team are able to understand and implement. I.e. it should identify and replace ‘ecology-speak’ with ‘construction-speak’ primarily through aligning recommendations with stages in / elements of the construction process, but also through the use of construction terms and minimising technical language. Contextual information should also be minimised; the primary aim should not be sign-off by the council ecology officer, but producing a practical working document for project implementation.

So what might this look like in practice? Typically within the ecology section of the CEMP there should be a series of actions or projects that cut across ecology topics as necessary. Vegetation clearance would typically be one such topic, the method for which would integrate mitigation for nesting birds, reptiles, etc. This is a step away from the structure of EcIA where mitigation is typically considered discretely as effects on each species / species group are assessed; and approach likely to be cumbersome for anyone trying to practically implement a CEMP.

An approach to translating mitigation into a series of separate non-technical actions is shown in Table 1.

Table 1: Structuring a CEMP – translating ecology-speak into construction-speak, with some examples.

Taking this logic further, as most CEMPs cover disciplines other than ecology, the ecological mitigation would, ideally, be fully integrated into the document, within a series of multidisciplinary actions arranged by construction stage, avoiding the need for a separate ecology section at all.

CEMP structure

The introduction should only cover essentials such as who the document was prepared by / for, and the planning application reference number. If there have been significant changes in the project programme or design, or significant time has elapsed and update surveys have been necessary, then a summary of the baseline and a risk assessment of potentially damaging activities may be unavoidable. However, this information, which might be primarily relevant to the LPA ecologist, should be appended. Existing publicly available information should be referred to (in links where possible) as opposed to reprised.

The main body of the CEMP should typically comprise a works schedule listing a series of actions, arranged chronologically by construction stage, followed by a series of method statements and a plan showing the locations of actions (e.g., locations of fences, setts for closure, new wildflower meadow, bat and bird boxes, etc.).

The CEMP should provide a method statement for each of the pre-construction and construction phase actions which should be as concise as possible. If measures cannot be captured clearly and simply, there is far greater scope for misinterpretation. The method statements should also be as self-contained as possible, so that they can be individually implemented if necessary. These method statements should describe:

  • the activity itself
  • when it should take place
  • who should carry it out
  • what equipment and materials should be used (e.g., digger size, seed mixes, etc.)
  • the need for direct ecological involvement
  • any checks, monitoring, or sign-off requirements.

Finally, method statements should draw on conversation with the construction team to ensure it will be workable. It may also be useful to provide a sentence on why an action is required (e.g., to avoid damage to active nests, which would be in contravention of wildlife legislation).


CEMPs should be written for the construction manager as the primary audience. The main task in writing one of these documents is presenting clear, non-technical, task-specific actions within short method statements arranged by construction stage as opposed to ecological feature / theme. If this can be done we will see better outcomes for nature and reflect the aspirations of EcIAs more accurately.

Further information on our habitat management planning capability can be found here: Habitat Management Planning

If you would like to discuss how we can help you with habitat management plans for your project please contact one of our offices.


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