When substances enter surface water through wastewater, it is essential to understand what this means for the quality of that water. An ABM assessment evaluates substances based on their environmentally harmful properties, while an immission assessment provides insight into the actual impact of a discharge on the receiving water body. Both assessments are indispensable in permitting procedures and form the basis for well‑substantiated decisions and permit conditions.

Cantech supports organizations in performing, evaluating, and applying ABM and immission assessments, ensuring that the effects of discharges are made transparent and that both companies and authorities have a solid, well‑founded basis for decision‑making.

When discharging substances into surface water, it must be demonstrated that they do not cause unacceptable risks. For this, two assessment methods are used in the Netherlands:

• ABM assessment (General Assessment Methodology): determines the water environmental risk of substances, meaning the extent to which a substance can be harmful to the surface‑water environment. Substances are classified as acceptable, suspicious of non‑permissible based on their environmentally hazardous properties (toxicity, degradability, and bioaccumulation).
• Immission assessment: evaluates the effects of a discharge on the water quality of the receiving surface water. It determines whether the discharge leads to exceedance of environmental quality standards or an unacceptable deterioration of the ecological and chemical status. The assessment takes into account dilution factors, background concentrations, and legal standards (such as WFD norms), providing insight into the actual load on the water system.

Together, these assessments form an important foundation for permit issuance. They provide insight into the environmental consequences of discharges and make it possible to substantiate permit conditions both legally and technically.

For companies, ABM and immission assessments are often part of the permitting process. The results show whether discharges remain within legal limits and what measures may be required.

For public authorities, these assessments are essential for evaluating permit applications and substantiating decisions on a solid technical and legal basis.

Cantech performs ABM and immission assessments and supports their application in permitting procedures. Our role can range from carrying out the assessments and preparing reports to providing second opinions and integrating the results into permit conditions or regulatory decisions.

With our expertise in both the technical aspects (water quality, assessment methodologies) and the legal context, we ensure that companies and competent authorities receive clear, reliable, and applicable results.

Curious what this means for your organization? Together, we’ll identify which assessments are required and how they can best be applied in your specific situation.