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The Ecological Clerk of Works (ECoW), or Environmental Clerk of Works (EnCoW), is an important role on construction and development sites, especially where there are potential ecological sensitivities. The terms EnCow and ECoW are often used interchangeably, although strictly speaking, an EnCoW will be responsible for all the environmental elements of a site (water, silt management, pollution, wildlife) whereas an ECoW will just monitor the wildlife.

Ecological Clerk of Works

In the most basic terms, an ECoW provides onsite monitoring to ensure that works are carried out in accordance with environmental legislation, but the specifics of the role will vary depending on the type of project. Sectors involved include residential housing, renewable energy, heritage and public utility construction.

The Role of an ECoW

First and foremost, the ECoW gives advice and support to the developer or contractor to make sure that wildlife laws are not contravened and that any ecological components of the planning consent are complied with.

This often begins with pre-construction monitoring for protected species and may involve some input into crucial documents such as the Construction Environmental Management Plan (CEMP) and Pollution Prevention Plan.

While the project is ongoing, the ECoW will monitor the site to ensure environmental legislation is followed and this might also involve water monitoring, continued wildlife surveys and species translocation, as well as watching briefs during activities such as vegetation clearance or building demolition.

Responsibilities will often also include:

  • Regular communication with all stakeholders
  • Liaison with local planning authorities and other relevant bodies, such as Natural England, Nature Scot or Natural Resources Wales
  • Consultation with non-governmental conservation organisations
  • Accurate and regular record keeping
  • Delivery of toolbox talks to site staff
  • Involvement in the construction of any mitigation measures required, such as habitat restoration
  • Activities such as silt management
  • Ensuring all required wildlife monitoring licences are obtained/up to date
  • Advice on protected species and habitats
  • Providing solutions to any issues that arise during construction works
  • Providing information to the public
  • Carrying out regular post-construction monitoring
Watching brief during cable pull
Starling inside an excavator exhaust
Fuel can on a plant nappy