top of page

Confirmation Bias and the role of the Environmental Clerk of Works (EnvCoW)

Is confirmation bias inhibiting the effective delivery of the EnvCoW role?

Across the construction industry, despite clear efforts to define the roles and responsibilities of the Environmental Clerk of Works (EnvCoW), the Ecological Clerk of Works (ECoW), and Environmental Advisors/Managers, confusion persists. This article seeks to clarify these roles and explore how confirmation bias might be affecting their application, potentially leading to significant environmental impacts—the very outcomes these roles aim to prevent.

Understanding these distinct roles

Environmental Clerk of Works (EnvCoW): As defined by the Association of Environmental Clerk of Works (AECoW), the EnvCoW is "an environmental professional with responsibility to monitor and report on environmental compliance". This role focuses on ensuring that all construction activities comply with environmental regulations and standards.

Ecological Clerk of Works (ECoW): An ECoW is an ecological specialist responsible for delivering ecological advice, performing surveys, or undertaking mitigation efforts – as outlined by the Chartered Institute of Ecology and Environmental Management.



Case studies: role application in practice

Throughout our workshops, such as the University of West of Scotland's Environmental Clerk of Works Foundation Course, we ask our delegates what they believe are the EnvCoW responsibilities. When we receive several different answers, it becomes evident that the EnvCoW's role is often confused with that of an Environmental Advisor/Manager or an ECoW.

It’s also our own observation that throughout a project impact assessment by environmental consultants, the EnvCoW role is often interchangeably used with an ECoW, leading to varied responsibilities across projects.

Real-world examples

In one impact assessment review Naturally Compliant undertook, we identified 13 inconsistencies relating to the roles of EnvCoW versus ECoW. This confusion is not isolated, as evidenced by frequent mislabelling in assessment chapters, such as:

"The Contractor will employ an Environmental Clerk of Works (ECoW) during the construction phase who will take a key role in the preparation of the CEMP."

The EnvCoW shouldn’t prepare a CEMP as this would be a conflict of interest, and monitoring your own success is tantamount to ‘marking your own homework’.

The most effective CEMPs are developed by the Contractor undertaking the work, as they know what has been costed and programmed for.


"The ECoW appointed to provide advice during construction and installation of water crossings... also ensure that pollution is minimised as far as possible. The ECoW would also advise on the need for any temporary watercourse diversions and the best way for these to be undertaken."

This mitigation commitment sees the ECoW with responsibilities for ensuring that pollution is minimised, whilst advising on the need for and method for temporary watercourse diversions.

This requires an ecologist to advise on pollution prevention and potentially complex hydrological issues. All while the interchangeability of the ECoW/EnvCoW role will likely see the requirement for them to monitor and report on their own work.


Potential direct effects can be effectively mitigated by an agreed programme of archaeological work to be overseen by an Archaeological or Environmental Clerk of Works (ACoW/ECoW).

Archaeology is a technical specialism, and their mitigation measures are something that neither an Environmental nor an Ecological Clerk of Works is qualified to oversee.


For reference, the Heads of Planning Scotland paper on ‘The role of the Environmental Clerk of Works’ provides a model condition which is closely aligned to the Energy Consents Units own model condition which states:

"There shall be no Commencement of Development unless and until the terms of appointment of an independent Environmental Clerk of Works (‘EnvCoW’) by the Company have been submitted to, and approved in writing by, the Planning Authority. The terms of appointment shall:

impose a duty to monitor compliance with the environmental commitments provided in the EIA Report, any micrositing under condition [10], the Construction and Environmental Management Plan approved under condition [13], the Habitat Management Plan approved under condition [18], [any species or habitat management plans identified in the EIA Report],2 [and other plans approved under condition[s] ]3 (“the EnvCoW works”);

For the following reason

To secure effective and transparent monitoring of environmental mitigation and management measures associated with the Development during the construction, decommissioning, restoration and aftercare phases.

Ultimately, Environmental Clerk of Works by definition and model condition should monitor compliance and report on compliance; an Ecological Clerk of Works should provide construction phase ecological support; and an Environmental Advisor / manager should provide construction phase environmental advice and management. These roles have materially different responsibilities that are not interchangeable.

These examples highlight the misuse of roles and the lack of clarity that still exists within the industry.

Inconsistency breeds confusion

The persistence of these inconsistencies necessitates a continued effort to educate and redefine the roles clearly and distinctly. Misuse of the EnvCoW and ECoW acronyms not only perpetuates confusion but also potentially undermines environmental management efforts.

Understanding the roles of the EnvCoW & ECoW & the impact of confirmation bias.


What is confirmation bias, and how does it affect the industry?

Confirmation bias is a cognitive bias that favours information confirming our pre-existing beliefs, as described by Kendra Cherry (MSEd) in her article, "13 types of cognitive biases that might be impairing your judgment". This bias influences how we gather, interpret, and recall information, often leading us to overlook contrary evidence.

Types of confirmation bias:

There are a few different types of confirmation bias that occur. Some of the most common are:

Biased attention: Focusing only on information that supports existing practices while ignoring data suggesting a need for change.

Biased Interpretation: Interpreting information in a way that reinforces current beliefs or practices.

Biased memory: Remembering details that support our views and forgetting those that do not.

Why confirmation bias is a problem

Within the construction industry, confirmation bias often manifests as a preference for "doing things the way they've always been done", even when such methods lead to incorrect applications of environmental roles. This bias can prevent industry professionals from learning from past mistakes, thus perpetuating inefficiency and environmental mismanagement.

Ensuring a project is compliant with its planning commitments i.e. the CEMP, sits squarely with the project’s proponent. They ensure that contractors adhere to environmental regulations and planning commitments. When the responsibility is incorrectly assigned to an independent EnvCoW, it misleads regulatory bodies into believing that compliance is assured, which is not always the case.

For example, “An Environmental/Ecological Clerk of Works (ECoW) will be appointed to ensure compliance with the CEMP”.

The problem is then compounded by developers, influenced by their own biases, procuring or asking their contractors to procure an “Environmental/Ecological Clerk of Works/Environmental Advisor” to meet their expectations, rather than what the planning condition is asking them for.

Additionally, when an environmental consultant during the construction phase offers to fulfil multiple roles, e.g. the ECoW, an Environmental Manager, and other technical services, AND the independent EnvCoW, this is a conflict of interest and compromised monitoring and reporting of data.

The result is a cycle of repeated errors and a lack of progression in the construction industry. Without clear and unbiased feedback from construction projects, the industry fails to recognise the true impacts of its activities, whether significant or not. This perpetuates inefficiency and environmental mismanagement.

Our best advice: addressing the issue

Impact Assessment Practitioners: Clearly delineate roles in impact assessments. Ensure that responsibilities are appropriately assigned to avoid conflicts of interest and ensure compliance.

A third-party EnvCoW can only monitor whether the project is following standards set, not guarantee it.

Developers: Understand and implement planning consents accurately. Engage environmental managers to coordinate environmental specialists effectively and utilise the data the EnvCoW provides as a feedback loop to inform future development.

Construction Phase Environmental Consultants: Recognise the potential for conflicts of interest when offering multiple services. Collaborate with those responsible for environmental compliance to achieve the best outcomes for projects and the environment.


By recognising and addressing confirmation bias, and by clearly defining and adhering to the distinct roles of EnvCoW and ECoW, the industry can improve its environmental management practices and reduce the likelihood of negative impacts on the environment. This approach will foster a more efficient, effective, and transparent construction industry.

If you’d like more information on this topic, or advice on your next project, please don’t hesitate to get in touch.


bottom of page