Prevent the dispersal of alien species

  • Design Projects
  • Ecology and Surface Water


Requirements and Criteria Type: 
  • Technical Specification (Requirement Specifications)

Main Objective: 

The operation and maintenance of infrastructure and construction works are challenging with regard to preventing the further dispersal of harmful alien species. To prevent such dispersal, you can combat the occurrence (goal of eradication), limit the occurrence or carry out no treatment.

Alien species often displace local biodiversity and therefore pose a major threat to Norwegian nature. Species that are considered to pose a high or very high ecological threat to Norwegian natural diversity are registered in the ‘Black List’. Many alien species which must be combated are often dispersed to new areas during the transport of aggregates or through discharges of ballast water from other areas.

By stipulating requirements regarding the registration, assessment and possible removal of alien species, you will prevent the unwanted dispersal of alien species, and thereby also safeguard valuable natural diversity. Appropriate procedures for the handling of materials and the cleaning of equipment will reduce the risk of introducing alien species.

Requirement Specification: 

The construction work must be planned so as to minimise the impact on biodiversity during the execution phase. The dispersal of alien species must be prevented by avoiding the dispersal of soil and plant material or the discharge of ballast water. The supplier must investigate whether alien species are present in the area and prepare a report which is completed well in advance of the completion of the planning of the facility, so that the developer has the opportunity to address the recommendations in the report.

  • The supplier must investigate whether materials which are to be brought into the planning area are clean, to ensure that no alien species are brought into the area.
  • The supplier must treat materials which could contain seeds or other dispersible parts of alien species, to prevent them from being dispersed.
  • The supplier must describe measures to prevent the dispersal of material during transport.
  • The supplier must describe the location for the treatment of materials that have come into contact with materials which could contain seeds from alien species or plant/soil diseases.

Documentation of the Requirement Specification: 

The report on alien species must include at least the following:

  • Registration (SOSI) of individual species with associated map coordinates
  • Table containing the names and brief descriptions of the species
  • Confirmation that the species are registered in the Species Map
  • Plan concerning the species which should be combatted and proposals as to how to remove them
  • The species must be registered in

Information about the Requirement Specification: 

Although the legislation regulates alien species, experience indicates that follow-up of this legislation is poor. The requirement clarifies the measures that the supplier must implement and what you as the client should follow up.

This requirement is particularly relevant to construction projects which are close to valuable habitats and vulnerable natural environments. Inspections should therefore be carried out as close to the start of development as possible. A search in the Norwegian Environment Agency's nature database map service for valuable habitats in the surrounding area may show which species are indigenous at the site. In order to identify as many species as possible, at least two inspections should be carried out between May and September.

You should also consider whether there are any local action plans which provide guidance as regards the preservation of natural diversity in the area.

Related links: 

Published: 25. Nov 2020, Last modified: 26. Nov 2020