CASE STUDY
Ecological Clerk of Works (ECoW) and Invasive Species Management
AVRIO were appointed by a large Construction Contractor to carry out Ecological Clerk of Works (ECoW) and Invasive Species Management works for a project entailing the decommissioning and rebuilding of a Wastewater Treatment Plant in County Donegal.
The project initially involved conducting invasive species surveys of the proposed works area and associated surrounding areas to identify the extent of invasive species present. Surveys identified the presence of Japanese Knotweed (JK) in numerous locations where works were to be undertaken, and as such suitable management was required. Following completion of the relevant surveys, an Invasive Species Management Plan (ISMP) was then developed.
The main objective of the Invasive Species Management Plan was to outline and communicate the best method of control of invasive species specific to this site and manage the works to ensure they were carried out to the specification outlined in the management plan.
Following the development of the Invasive Species Management Plan, works could then begin to remove Japanese Knotweed from the required areas of the site. Prior to commencing any works, a full site induction was undertaken by AVRIO’s ECoW with all relevant construction employees. The purpose of this induction was to inform all construction workers of:
- What Japanese Knotweed is;
- How can Japanese Knotweed be identified;
- Why and how should Japanese Knotweed be treated with caution; and
- The Do’s and Don’ts in relation to Japanese Knotweed.
On completion of induction, a bio-secure area was created to limit the possibility of on and offsite transport of Japanese Knotweed contaminated material. Biosecurity protocols were strictly implemented and adhered to throughout the duration of the works. A bund area was then identified on-site and set up to receive the contaminated material. The bund is a contained area that will allow for the storage and future management of Japanese Knotweed contaminated material. Excavation of areas containing Japanese Knotweed was then carried out under the continuous supervision of AVRIO’s ECoW, with all contaminated material being appropriately transported to the bund. The bund area was levelled off and tidied up following all excavation works. All plant and machinery were cleaned appropriately and inspected before leaving the bund area to prevent any spread of Japanese Knotweed. Fencing was erected around the bund to ensure the area was not tampered with during the remaining construction phase or the future operational stage of the Wastewater Treatment Plant.
The bund area was put on a treatment plan consisting of an annual inspection and, if required, systemic herbicide treatment in September / October and repeating visits until two years evidence of no regrowth is achieved. When two years evidence of no-re-growth is achieved, the area will be landscaped with no soil being removed offsite. The Invasive species Management Plan was updated to compile a record of all relevant works undertaken. The management plan will be regularly updated with all necessary future treatment records to reflect the works undertaken.
The works were completed on time and within budget, and all parties involved were pleased with the project outcomes. Monitoring in line with the Invasive Species Management Plan is now ongoing.